FAA AC 20-42D - Advisory Circular

l l. Natio n al F ire Protection Association (NFPA) ...................... .. ........... .. ..................... .. .. A3 -5 12. RTCA lnc. D oc um en ts ..... ............................................................................................ AJ -6 13. SAE Documents............................................................................................................ AJ-6 14. Underwriters Laboratories, lnc (UL) ............................................................................ A3-6 iii 01/14/1 1 AC 20-420 Paragraph Page Appendix 4. Explanatory Material ... .............................................................................. A4-1 I. Effective Throw Ranges............................................................................................... A4- l 2. Safe-Use Guidance....................................................................................................... A4-1 3. Extinguisher Weights.................................................................................................... A4-4 4. Aircraft Volumes and Ventilation................................................................................. A4-5 Figure I. Table of Figures Relative Toxicity of 5 B:C Halocarbon Exting ui shers ................................... J 8 Figure 2. Mininmrn Number of Hand Fire Extinguishers Required for Transport Category Aircraft Passenger Compartments . ...... ......................... ..... .. ....... ....... ..... 24 Fig ure 3. Minimum Number of Hand Fire Extinguishers Required for Transport Category Rotorcraft Passenger Compartments ...................... , ............................... 25 Figure 4. Effective Throw Ranges for Halocarbon Halon Replacement and Water Extinguishers ........................................................ ... .... . . ............. A4- l Figure 5. Safe-Use Agent WN for Halocarbon Extinguishers in Unventilated Passenger and Crew Compartments .... .... .... ........ .. ...............................A4-2 Figure 6. Multiplication Factors (MF ventilated) for Ventilated Compartments ................ A4-2 Figure 7. Minimum Safe Compartment Volume for One Exti nguisher in UnventiJated Compartments .............................. . ...... ....................... ........ .......... A4-4 Figure 8. Fi re Extinguisher Performance and Gross Weights ........ ...........................A4-5 Figure 9. Aircraft Vo lumes and Ventilation ................................................. . ..... A4-6 iv 0J/14/ 11 AC20-42D Chapter 1. General Information about this Advisory Circular {AC} I . What is the Purpose of this Advisory Circul ar (AC)? a. We provide guidance for fue-figbting effectiveness, selection, location and mounting of hand fire extinguishers. b. We establish the halocarbons hydrochlorofluorocarbon (HCFC) Blend B, bydrofluorocarbon ( HF C) -227ea, and HFC-236fa as FAA approved replacement agents to Halon 12 I 1 and Halon 1301. c. This AC recommends that you transition to using th ese n ew hal ocarbon clean agents in fire exti nguishers kept onboard aircraft and rotorcraft. We explain how to gain certification for halocarbon clean agent extingujshers intended to replace Halon 12 11 hand-held ex tinguishers. d. This AC recommends that dry chemical, dry powder, and carbon dioxide hand ex tinguishers, in general. should not be used in aircra ft . e. We also explain how to gain Federal Aviation Administration (FAA) certification for replacement agent fire extinguishers, which you m ay u se to comply wjth Title 14 of the Code of Federal Regulations (14 CFR) parts 23, 25, 29. 91, 121 , 125, 127, and 135 . f. This AC establishes an FAA approved minimum performance standard (MPS) for halon replacement agents wh.ich includes a hidden fire test and a seat fi re/toxici ty test. g. This AC recognizes that toxicity of halocarbon agents and their decomposition products is a conccm and should be a consideration for extingui sher sel ec ti on . However, given the variabi Iity of extinguishers, application, compartment sizes and air change times, establishing specific se lecti on criteria is impractical. The toxicity hazard is a secondary concern to an unextinguished in-flight fire. h . This AC provides new general guidance in lhe form of safe-use weight -per unit volume (W/V) that may be use fuJ in extin guisher se lection, and establishes marking criteria for halocarbon extinguishers. i. We show how to reduce the health and safety ri sk of exposure to halocarbon clean agents and how to use halocarbon clean agent fire extinguishers. j. We offer updated guidance on the continued safe-use of Halon 1211 , H alon 1301, and Halon 1211 / 130 1 Halon blend extinguishers. 01/14/11 AC 20-42D k. This AC is not mandatory and does not constitute a regulation. It is not intended to require you to do anything beyond what is specifically required by the regulations. In it. we describe an acceptable means , though not the only means, to gain certification for fire extinguis hers kept ooboard aircraft and rotorcraft. However, if you use the means described, you must follow it entirely. 2. Who is this AC for? a. We wrote this AC for those responsible for selecting, approving, purchasing, and maintaining hand fu-e extinguishers. The guidance in this AC is also for manufacturers, installers, modifiers, owners, and operators of airplanes and rotorcrafr. b. This AC is a method of compliance for transport category aircraft. Operators of non- transport category airplanes or rotorcraft should become familiar with the information, precautions, and the safe-use guidance in this AC. c. Existing halo11 handhe1d fire extinguisher installations are not affected by the updated guidance in this AC. The guidance in prior revisions of this AC applies to specific extinguisher fostallations on existing approved type design aircraft. These extinguishers remain suitable for continued use based on a history of safe use of halon extingufahers on aircraft. However, although not required for new installations and in-service aircraft where practical, we encourage owners and operators to consider using FAA approved halon replacement extinguishers. 3. What has Changed in this AC from the Previous AC? a. Replac ement halocarbon clean agents were developed in response to restrictions on the production of ozone-depleting halon fire extinguishing agents. The restrictions were introduced under the Clean Air Act Amendments of 1990 which implemented the Montreal Protocol signed September 16, 1987, as amended. In addition, the International Civil Aviation Organization is considering further mandated limits on l1alon use in aircraft. b. Since 1994, Halon 1211 bas not been produced in the U.S. By 2010 , Halon 1211 will no longer be produced anywhere in the world. However, recycled Halon 1211 is available for new and existing fire extinguishers. Halocarbon clean agent extinguishers hydrochlorofluorocarbon HCFC Blend Band hydrofluorocarbons HFC-227ea , and HFC-236fa are now commercially available. These halocarbon hand fire extinguishers have been evaluated and found to be effective fire-fighting agents. If properly used, these agents are safe to human health. c. Safe-use guidance is provided for Halon 1211 and Halon 1301 and blends of these agents. Safe-use concentratio ns of Halon 1211 are lower than in the previous AC, because the guidance in this AC is more conservative. 2 01/14/ 11 4. Docs This AC C ancel Any Prior ACs? This AC cancels AC 20-42C, dated March 7, 1984. 5. Where Can I find This AC and Other FAA Publications? You can find this AC on the Regulatory and Guidance Library (RGL) website: hrtp: rgl.foa.gc.w '. See appendix 3 in this AC for additional information and related documentation. 3 01/14/11 AC 20-42D Chapter 2. Gaining FAA Approval for Fire Extinguishers 1. How are Hand Fire Extinguishers Approved? a. Federal Regulations for Hand Fire Extinguishers. Hand fire extinguishers are required under 14 CFR §§ 23.851, 25.851(a)(l), 29.851(a)(l), 29.853(e) & (f), 91.513(c), 119.25, 12l.309(c), and 135.155. We approve hand fire extinguishers to be used on aircraft W1der the provisions of 14 CFR § 21.305(d). Accordingly, this AC is provided as one means acceptable to us for the approval of hand fire extinguishers, other than water solution extinguishers approved under TSO-Cl 9. Note: Although 14 CFR parts 91 and 125 don ' t require our approval of hand fire extinguishers. we consider the infonnation in this AC acceptable for use by P art 91 and I25 operators. b. Ex tinguishers Approved Under lndustry Standards Organizations. We approve hand fire extinguishers for use in aircraft when they meet industry standards. Extinguishers approved in this manner should also meet the safe-use guidance provided in this AC. In addjtion, replacement agents must meet additional requirements specified in paragraph 2 below. We accept hand fire extinguishers approved by: (1) U.S. - Underwriters Laboratories, Inc. (U.S. - UL) according to U.S. - UL Standard 7 I I, Rating and Fire Testing ofFire Extinguishers, and U.S. - UL construction and performance requirements for specific agent extinguishers with a U.S. - UL Listing mark (See paragraph 3c below.) or equivalent such as: (2) Factory Mutual Research Corporation (FM) with listing mark, or (3) The U.S. Coast Guard (USCG) with marking per 46 CFR § 162.028. c. Minimum Rating. Your hand fire extinguisher should be rated per the requirements of U.S. - UL 711. dated December 17, 2004 or equivalent, as noted in paragraph lb above. Hand ex tingui shers produced in the U.S. or tho se used on airplanes and/or rotorcrafi operated within the U.S. should meet U.S. - UL fire rating standards. (l) Large Aircraft. The required hand extinguishers sho uld be listed and have a minimum U.S - UL 58:C rating or the equivalent. Exception: See chapter 4, paragraph 5 of this AC for minimum extinguisher ratings for use in accessible cargo compartments. (2) Small Airplanes or Rotorcraft. You may use an extinguisher with a minimum rating of U.S. - UL 2B:C or equivalent on aircraft with maximum compartment volumes ofup to 200 tr3 . 4 01/14/11 AC 20-42D 2. How are Halon 1211 Replacement Ex tinguishers Approved? Hand extinguisher replacement agents. such as the halocarbon clean agents intended to replace lhe required 2 ½ pound U.S. - UL 58:C Halon 1211 extinguishers, may be approved for use on aircraft if the ageat complies with the following requirements: a. Replacement Agent Health and Enviro nment App roval (1) Evaluate any halon replacement agent using the U.S. Environmental Protection Agency (EPA) Significant New Alternatives Poli cy (SNAP) program according to 40 CFR part 82, subpart G. This process characterizes the health and environmental risk of a proposed replacement agent. (2) The three halon replacement agents covered by tbfa AC were evaluated under the SNAP program. Halocarbon clean agents HCFC-Blend B, HFC-227ea, and HFC-236fa are approved for environmental and toxicological acceptability. b. Rep lacement Agent Band Extinguisher MPS. Evaluate the replacement agent/extinguisher using the two fire tests specified in the MPS technical report cited in appendix 3 paragraph 7s. MPS testing of replacement agents should be coordinated with and approved by yow· local ACO with the support off AATC. These fire tests ensure that the replacement agent extinguishers prov id e equivalent fire fighting performance to Halon I 21 J. Clean agent extinguishers designed to replace the required 2 ½ pound Halon 121 I extinguisher onboard aircraft should comply with the following MPS provisions; (I) Hidden Fire Test. The hidden fire test evaluates the ''flooding'' characteristics of the replacement agent against a bidden in-flight fire and determines the ability of a streaming agent to function as a flooding agent. This is a hardware-specific test and the extinguisher design affects its perfonnance. Each required 5B:C extinguisher model should pass this test to be certified as a Halon l 21 1 replacement on aircraft. (2) Seat Fire/Toxicity Test. The seat fire test is a baseline test that evaluates the effectiveness of the replacement agent in fighting a flammable fluid seat fire scenario and the associated toxicity hazard of the decomposition products of that agent. This test measures the agent's abili ty to extinguish a triple-seat fire in an aircraft under in-flight conditions and ensures an acceptable level of toxicity for the thermal decomposition products of the replacement agenl If a particular required 5B:C extinguisher model passes the seat fire/toxicity test, other models of extinguishers do not need to be tested, if the same agent is used Note l : Select a replacement agent or halocarbon extinguisher for your aircraft compartment according to the fire rating per its U.S UL listing. not the agent weight. Note 2: The effectiveness of a hand fire extinguisher relies upon the training, expertise and capabilities of the crew member utilizing the device. 5 01/14/11 AC 20-42.D (3) HCFC-Blend B, HFC-227ea, and HFC 236fa have demonstrated to meet the MPS and are approved for use. c. National Certification. U.S. - UL 2129, Halocarbon Clean Agent Fire Extinguishers, dated January 3, 2007 with a required rating of U. S. - UL 5B:C or equivalent per U.S. - UL 711 or equivalent (see paragraph lb above). Note: Use the FAA approval marking label, (see paragraph 2e below) and the U.S - UL numeric rating listing, not the agent weight to select extinguishers for an aircraft compartment. d. Specifications fo r Approved Halocarbon Cle an Agents to Replace Halon 12 11. For hand fire extinguisbers employing halocarbon clean agents replacing Halon 1211, the following American Society of Testing and Materials (ASTM) specifications apply: (I) HCFC Blend B must meet ASTM D 7122-05, Standard Specifications for HCFC Ble nd B; (2) HFC-227ea must meet ASTM D 6064-03, Standard Specfficationsfor HFC-227 ea, 1,1,1,2,3,3,3-1-Jeptafl,owopropane (CF1CHFCF1)i (3) HFC -236fa must meet ASTM D 6541-05, Standard Spec ification for HFC-236a, 1.1,1.3.3,3-Hex~fluoropropane (CF1CH 2CF3)~or (4) New Halon 1211 replacement agents must have and meet an applicableASTM or equiv alent specification. (5) Fire extinguisher manufacturers are responsible for the validation of agent purity whether using new or recycled agent. e. Marking. If you are a manufacturer, each of your models of U.S. - UL 5B:C Hal on 1211 replacement extinguishers that have passed the test specified in paragraph 2b( 1) and 2b(2) above should be permanently and legibly marked wjth the following: (1) ''Meets FAA approved MPS per DOT/FAA/AR-01 / 37" (2) The name of the listing agency and rating according to U .S. - UL 711 or equivalent. U.S. - UL extinguishers must have the UL listing mark (include UL copyright logo) with the four required elements: UL in circle mark: word "listed;'' product or company name; and issue/serial number or control number. f. New Technologies and Extinguishe rs Contaioi.ng New Replacement Agents. Nothing in this AC is intended to restrict new technologies or use of new rep l acement agents provided they meet the regulations and guidance prescnbed in paragraph 2 above. 6 01/14/ 11 AC 20-42D (l) New agents introduced after the effective date of this AC should comply with the provisions of paragraph 2a through 2e above. (2) If the documentation needed in paragraph 2f(l) is not yet officially published for a particular halocarbon agent, u se the NOAEL values approved under the SNAP program mentioned in paragraph 2a(l) above. They can be obtained from the SNAP Program Coordinator at the EPA Office of Air and Radiation or on the public docket for that office and used lo determine safe-use W/Vs in the absence of published FAA safe-use guidance. Safe-use WNs may be calculated using EPA 's NOA EL values following the methodology outlined in append 1x 3 refere nce paragraph 7 m of this AC. (3) The FAA Technical Center (FAAT C) intends to publish future guidance on handheld extinguishers. Tb.is guidance will include safe-u se WN fo r ventilated compartments using FAA approved fire extinguishers conta ining halon replacement agents intro du ced after the issuance of this AC. 3. flow are Ba lon Extinguishers Approved? a. National Certification. Required halon hand-held fire extinguishers approved for use on air craft sh ould ha ve a minimum rating of UL 58:C. Halon 130 1 and Halon 1211 /1301 blends are also used. Halogenated fire extinguishers must co mply with U.S. - UL 1093, Halogenated Agent Fire Excinguishers, or equivalent, for Hal on 12 1 l, H alon 130 l and Halon 1211 / 130 1 blends per U.S. - UL 711 or equivalent (see paragraph lb above). 1l should be noted that on March 1 2, 2009, UL announced the withdrawal of US - UL 1093 and the continuance of existin g certifications to the withdrawn US - UL 1093. U L will no longer accept the submiltal of n ew or revised pro du cts. but a11 current compliant products covered und er US - UL 1093 will continue to be authorized to bear the clas sification mark of Underwriters Laboratories Inc. until October 1, 20 14 . b. Specifications for Approved Balon Agents. For hand fire extinguishers th at still emp loy ha logenated agents, only Ha lon 1211, Halon 130 l, or b le nds o f the two have been previously approved and used aboard aircraft. The follow ing spec ifications cover the requirements for halogenated agents: ( I) Halon 12 J l should meet the requirements of ASTM D76 73 -10, Standard Specificarion for Halon 1211-Bromochlorodifluoromethane (CF1CIB 1~). or ISO 7201-1 :1989, Fire protection -- Fire extinguishing media -- Halogenated Hydrocarbons - Part 1: Specifications for Halon 1211 and Halon 1301. (2) Ha lon 130 l should meet the requirements of ASTM D5632-08. Standard Specificarion for Halon I 301-Bromotrijluoromethane (CF3Br}), or ISO 7201-1: 1989. 7 01/14/11 AC 20-42D (3) Hand fire extinguishers with halon agents may continue to be used on aircraft as long as recycled halon of proven acceptable quality is available. Recycled agents are still available for purchase, but the duration of their availability is unknown. Therefore, we encourage operators to consider replacing halon extingwsbers after discharge with approved halon replacement extinguishers. (4) An EPA exemption allows the production of halon blends from recycled halon for aircraft use. There are strict conditions to this exemption. (5) Fire extinguisher manufacturers are responsible for the validation of agent purity whether using new or recycled agent. c. Marking. If you are a manufacturer, mark your halon extinguishers pennanently and legibly with the name of the listing agency and rating according to U.S. - UL 7 11 or equivalent. U. S. - UL extinguishers must have the UL listing mark (include UL copyright logo) with the four required elements: UL in circle mark; word "listed ;" product or company name; and issue/serial number or control number. FM extinguishers must have the FM listing mark. And, USCG extinguishers must have the ..USCG approval 162.028/XX'' marking. 8 01/14/ 1 J AC20-42D Chapter 3. Selecting the Correct Hand Fire Extinguisher L. What are the Different Types of Fires? a. Classes of Fires. To properly select an appropriate hand fire extinguisher for use in an aircraft. you should consider the following classes of fires that are likely to occur onboard your aircraft, as defined in the appendix 3, paragraph 1 la of this AC. (1) Class A. Fires fovolving ordinary combustible materials, such as wood, cloth, paper, rubber, and plastics. (2) Class 8. Fires involving flammable liquids, petroleum oils, greases, tars, oil base painls, lacquers, solvents, alcohols, and flammable gases. (3) Class C. Fires involving energized elec tri cal equipment where the use of an extinguishing media that is electrically nonconductive is important. (4) Class D. Fires involving combustible metals, such as magnesium, titanium, zirconium. sodium, lithium, and potassium. b. Lithium Battery Fires. Do not treat a fire involving a small number of lithium batteries as a Class D fire. We consider a small number of rechargeable lithium batteries as what wo uld be found in portable electronic devices (PED) e.g. laptop computers, cell phones, pagers. audio/video/data recording or playback devices, messaging devices, personal digital assistants ( PDAs), and two-way radios. See chapter 4 paragraph If of this AC on fire fighting training for further information. 2. What do th e Numeral Ratings Mean? The labeling on fire extinguishers consists of numerals and letters used in combination to describe the extinguishers relative effectiveness on a specified C lass/type(s) of fire(s). a. Numerals are used W1th identifying letters for extinguishers labeled for Class A and Class B fires. The " num er al ," which precedes the letter, indicates the relative extinguishing effectiveness of the device on a given size fire. This is dependent on the agent, the capacity of the device, di sc harge times, and design features. Fo1· example, an extinguisher rated as U.S. - UL 4A should extinguish abo ut twice as much CJass A fire as a U.S. - UL 2A rated extinguisher. Numer aJ ratings are not used for extinguishers labeled for Class C or D fires. Extinguishers that are effective on more than one class of fires have mul tiple "numeral-letter" and " letter" clas sifications and ratings; for example, U.S. - UL 58 :C. 9 01/14/11 AC20-42D b. Additional Rating Guidelines for Halocarbon Extinguishers. For occupied spaces on transport category aircraft, extinguishers employing halocarbon clean agents, replacing required Halon 1211 extinguishers, should have a minimum U.S. - UL 5B:C or an equivalent rating. Halocarbon extinguishers are most effective on Class B and C fires. Extinguishers with greater capacity are also rated for Class A fires. Extinguishers with a 2B:C or 5B:C U. S. - UL rating, although not rated for use on Class A fires, have been shown to be effective in extinguishing surface Class A fires. 3. What Extinguishing Agents are Appropriate for the Different Types of Fires? The following extinguishing agents are appropriate for use on the types of fires specified in paragraph la above: a. Water. Class A type fires are best controlled with water by cooling the material below its ignition temperature and soaking the material to prevent re-ignition. b. Carbon Dioxide. Class B or C fires are effectively controlled by carbon dioxide as a blanketing agent. Note: Carbon dioxide is not recommended for hand-held extinguishers for internal aircraft us e. c. Dry Chemicals. Class A, B, or C fires are best control1ed by dry chemicals. The only "all purpose" (Class A, B, Crating) dry chemical powder extinguishers containmono amrnonium phosphate. All other dry chemical powders have a Class B. C U.S - UL fire rating only . Note 1: In general, dry chemicals are not recommended for hand extinguishers for internal aircraft use, due to the potential for corrosion damage to electronic equipment, the possib1Jity of visual obscuration if the agent were discharged into the flight deck area, and the cleanup problems from their use . Note 2: When approving a non-gaseous agent for instaJlation on aircra~ evaluate the contamination impact to the structure, wiring and surrounding systems, and consider potential mixing of the agent residue with water. Using such extinguishers may require specific maintenance procedures addressing cleanup. d. Halons. Class A, B, or C fires are approp1iately controlled with halons. However, do not use halons on a class D fire. Halon agents may react vigorously with the burning metal. Note: While balons are still in service and are appropriate agents for the se classes of fires, the production of these ozone depleting agents bas been restricted. Although not required, consider replacing halon extinguishers with halon replacement extinguishers when discharged. 10 01 / 14 / 11 AC 20-42D e. Halocarbon Clean Agents. (Ha Ions are a subcatego,y of ha/ocarbons.) Class A, B, or C fires are appropriately controlled with the use of halocarbon clean agents. Never discharge halocarbon clean agents or water on a Class D (burning metal) fire. Halocarbon agents may react vigorously with the burning metal. r. Specialized Dry Powder. Class D fires are best controlled by dry powder. Fo11ow the recommendations of the extinguisher manufacturer because of the possible chemical reaction between the burning metal and the extinguishing agent. Note 1: Specialized dry po wder is not recommended for hand extinguishers for internal aircraft use. Note 2: Fires involving a small number of Lithium primary batteries (containing molten Lithiwn) should not be treated as class D fires and specialized dry powder shou ld not be used. See chapter 4, paragraph lf of this AC for a discussion of appropriate exti nguishing agents for Lithium battery fi res. 4. What Extinguishing Agents are Compatible with Aircraft Material s? a. Corrosion by Extinguishing Agents. Halocarbon clean agents are not corrosive, but review the material compatibility properties for acceptability to aircraft materials. Water itself is not corrosive, but may be rendered corrosive by the addition of antifreeze solutions. Specialized dry powder and monammonium phosphate dry chemical are corrosive to most sensitive electronic components and instruments. b. Material Compatibility. Halocarbon clean agents can be used in numerous aircraft applications and it is important to review the materials of construction for compatibility when designing new equipment, retrofitting existing equipment. or preparing storage and handling equipment to in corporate halocarbon clean agents. Materials that should be considered include metals. elastomcrs, and plastics. Halocarbon dean agents or water should never be di scharged on Class D (b urning metal) fires. These agents may react vigorously with the burning metal. See paragraph I b above for the exception: Lithium battery fires involving carry-on appliances. c. Corrosivity of Decomposition Products. The the 1mal decomposition products of halocarbon extinguishing agents are corrosive, particularly the acid halides: HF , H Cl and HBr. The decomposition products of burning aircraft materials are al so corrosive. Yet decomposition products are minimized by quickly extinguishing the fire. Acid halide production is also based on the agent used and the size of the fire. 5. What are the Operating Temperature Tolerances? a. Halocarbon clean agent extinguishers shouJd operate properly after being conditioned al -40°F {-40°C) or -65°F (-54°C) as applicable and 120°F {49°C) for 16 hours as specified in U.S. - UL 2129 or U.S. - UL 1093, as app li cable. Water ex1inguisbers should be protected to -40°F (- 40 ° C) by adding antifreeze and stipulated on the extinguisher nameplate. I1 01/14/11 AC 20-42D b. Cold operation may require additional consideration in the selection of an extinguisher. This is particularly true for general aviation aircraft in extremely cold climates. The hidden fire extinguishment tests in the MPS were conducted on halocarbon extinguishers equilibrated to 70°F. More agent, a lower boiling point agent, or an extinguisher design change, may be needed to extinguish hidden fires. Testing may be needed to select an appropriate extinguisher. The boiling points of the balocarbons (at 1 atmosphere) listed in this AC are: (1) HCFC Blend B = 80.6°F (27.0°C), (2) HFC-227ea = l .9°F (-16.4° C) , (3) HFC-236fa = 29.5°F (-1.4°C) , (4) Halon 12 11 26.0°F (-3.4°C), and (5) Halon 1301 = -72.0°F (-57.8° C) . 6. General Guidelines for Hand Fire EA1inguishers. a. Consider the effects of agent toxicity, aircraft ventilation, agent stratification and hypoxia when selecting and sizing the necessary fire extinguisher for your specific application. Chapter 4 of this AC provides more detail s. b. Provide the required minimum nW11ber of hand held extinguishers. See chapter 5, paragraph4 of this AC. Alt extinguishers must have the proper U.S. - UL rating, even in spaces where the safe use guidelines, as outlined in chapter 4 paragraphs 2, 4, 5, and 6 of this AC, are exceeded. The failure to extinguish a fue has catastrophic consequences for all aircraft occupants. Agent toxicity should be considered secondary to the immediate need to extinguish the fire. c. Follow the safe-use guidance recommendations in chapter 4 of this AC for selecting extinguishers for your aircraft compartments to, " ...minimize the hazard of toxic gas concentration .. .''. mentioned in 14 CFR §§ 23.851(c)(2), 25.85l(a)(8), and 29.851(a)(3). d. Do not substitute two smaller extinguishers for one extinguisher of the proper UL rating, except as provided for accessible cargo compartments, as noted in chapter 4, paragraph Sc of this AC. The fire can grow quickly prior to the discharge of the second extinguisher. e. Due to the relatively short discharge time ofhand fire extinguishers: a U.S . - UL 5B and a U.S. - UL l A: 1OB:C rated extinguisher at approximately 8 seconds; and 13 seconds for a U.S. - UL 2A: l 0B:C extinguisher; training on the proper use of the fire extinguishers is very important. 12 01 /14/ 11 AC 20-42D f. For access to under seat, overhead, and other difficult to reach locations, hand extinguishers equipped with a discharge hose or adjustable wand mounted directly to the extinguisher are highly recommended. A discharge hose or adjustable wand is preferred because it is likely to result in the extinguisher being properly held in an upright position during use and provides a means of directing a stream of agent to more inaccessible areas. Adjustable wand or fixed nozzle extinguishers allow for one-handed use. See AC t 20-80 for more details and guidance on in-flight fire fighting. A video for flight crew training is available from the FAA. The title of the video is ''Aircraft ln-fliglu Fire Fighting." 111e tape version of the video is referenced as ''MST 730" and the DVD version is referenced as "MS T 730.01." It can be obtain ed from Dale Dingler.FAA William J. Hughes Technical Center, Advanced Imaging Division, AJ P-7960, Atlantic City International Airport, NJ 08405. ph one: (609) 485-6646, ema iJ:dal e.ding1er@faa.gov. The in-flight training video is also availab le at the fo11owingpublic website: httr://www .ti re. tc. faa . gov/2007Conforence/ses!-i ion _ detai ls.asp'?sess1onlD=26. g. U.S. - UL 5B:C extinguishers should have no le ss than an 8 foot (3 m) throw range (passing the MPS seat tests assures a 8 foot throw range). Longer throw ranges of 10 feet and greater provide a significant advantage in fighting fires in large transport category aircraft. See appendix 4, paragraph I of this AC for more infom1ation on replacement agent throw ranges. h. Halocarbons that are gaseous upon discharge have a more limited throw range. HaJocarbons have discharge characteristics dependent on the halocarbon, nozzle design, extinguisher s up er pressurization, cold soak times. and operational temperatures. 7. Replacement of TSO Water Extinguishers: a. Halon replacement extinguishers with a minimWTI rating of 5B:C can be used in place of required tec hni cal standard order (TSO) C19 water extinguishers, if you can show that the replacement extinguisher has comparable or better Class A extinguishing performance than the TSO'd water extinguisher. A TSO Cl 9 water extinguisher can fight small Class A fires but are not large enough to have a lA rating. Toe halon replacement exti ngu isher mu st have a sufficient throw range to extinguish fires likely to occur. b. For aircraft that are required to carry two or more extinguishers and two water extinguishers are in cl ose proximity, the two water extinguishers may be replaced by one halon replacement extinguisher. This is allowed only if the extinguisher has been shown to have comparable or better Class A fire extinguishing capability as both water extinguishers and a sufficient throw range to extinguish fires likely to occur. 13 01/14/11 AC 20-42D Chapter 4. Safe Use of Hand Fire Extinguisher 1. What Basic Fire Fighting Training Should be Provided? a. Flight crewmembers should be trained on the urgency of immediate and aggressive extinguishment of an onboard fire. As fires can grow exponentially with time, the risks of exceeding the hazardous concentration levels of extinguishant are considered minimal compared to the risks of an in -fl ight fire. (1) Quickly extinguish the fire. (2) Inunediately tum off all air recirculation systems, as permitted by your flight manual. b. Train flight crewmembers on the proper use of hand extinguishers. See ACl 20 -80. In-Flight Fires, for additional guidance. A training video on the use of hand extinguishers to fight on-board tires is available at the following website: hltp://www.fire.tc.faa.gov/2007Co nforen ce/sess ion_ details.asp?~essionl D-=16. c. Operators should ensure that all crew members receive proper training in the appropriate use of hand fire extinguishers onboard their aircraft d. Attack the base of the fire at the near edge of the fire and then move the fire extinguisher nozzle with a side-to-s ide sweeping motion, progressing toward the back of the fire. The optimu m firefighting technique differs for each approved extinguisher. e. Do not direct the initial dischar ge at the burning surface at close range _, if the burning material might sp lash and/ or splatter. f. Lithium Battery Fires. Crew members sho uld be trained not to treat a small number of lithium batteries as a C la ss D fire. Halon , Halon replacement, or water extinguishers cru1 be used to control fires invo lving a smal l number of rechargeable lithium batteries as found in PED e.g. laptop computers, cell phones, pagers, audio/video/ data recording or playback devices, messaging devices, PD As, and two-way radios. Water or other water based liquid from any available source should be poured over the cells immediately after fire knockdown or extinguisbment , s ince only water or water based liquids can provide sufficient cooling to prevent re-ignition and/or propagation of the fire to adjacent cells of the battery pack. A water extinguisher , by itself, can be used safely (from a distance) to extinguish a lithium battery fire and will usually coo l it sufliciently to end the event. [f needed, it can be followed up by water from any available s ource . (I) Crew members sho uld be trained not to use fire resistant bum bags to isolate burning Lithium batteries. Transferring a burning appliance into a burn bag may be extremely hazardous. l4 01/14/11 AC 20-42D (2) See SAFO 09013 and the training video refen-ed to in paragraph 1 b above for further guidance on how to fight Lithium battery fires. 2 . What are Some General Guidelines for the Safe-Use of Halocarbon Extinguishers? a. QuickJy Extinguish the Fire. Although exposure to halocarbon agents and their decomposition products are a concern, it is far less of a concern than the consequences of an unextinguished in-fligbt fire. It is critically important to quickly extinguish an in-flight fire. The consequences of an unextinguished in-flight fire include the loss of the aircraft and its occupants and immediate toxic hazards from exposure to thermal decomposition products of the burning materials, including carbon monoxide, hydrogen cyanide, smoke, heat, and subsequent oxygen depletion. b. Control Exposure to Combustion Gases and Halocarbon Vapors. The following guidance is affected by and may be adj usted for agent stratification and localization, as discussed in chapter 4, paragraph 4b(4 ). ( 1) Turn off all air recirculation systems immediately, ifallowed by your aircraft flight manual (AFM) or flight crew operations manual (FCOM). Halocarbon agents are much heavier than air and under mo st conclitions they stratify with time at lower leve1s. Turning off the recirc ulation al lows the agent entering the low level air returns to be directed to the air outfl ow valves and out of the aircraft. This increases the rate of agent removal from the aircraft. Some aircraft have up to 50% recirculation, so it is impo1tant to tum off the air recirculation quickly. (2) While it is impossible to accurately predict the hazard level in most situations, try to avojd selecting extinguishers that could result in exposure to halocarbon vapors above the safe-use levels. Exposure may result in clizziness, impaired coordination, reduced mental acuity, and heart arrhythmias. (3) Halocarbon agents also decompose when they contact open flames or hot surfaces. The decomposition products have a characteristic sharp, acrid odor, and an eye irritating effect, even in concentrati ons of only a few parts per million. See Annex A, Paragraph 1.5.1.2 and 5. 7.1.2 of the standard in appendix 3, paragraph l ld of this AC , or the most current revision, for more detailed information on the effects of neat agent and hydrogen fluoride (HF) respectively , as well as further discussion of factors affecting the fonnation of thermal decomposition products. c. Use Portable Protective Breathing Equipment (PBE). Jn compartments where extfoguisher(s) are used that do not meet the safe-use guidance in this AC, flight crewmembers should use portable PBE, if available and/or as directed by FCOM procedures or AFM . Unprotected personnel shou ld not enter a protected space during or after agent discbarge, until ventilated. Crewmembers should follow fire :fighting procedures when using portable PBE. See paragraph Sb below for additional information on portable PBE use in cargo compartments. 15 01/14/1 I AC 20-42D d. Ventilate the Compartment. (l) When you are reasonably sure the fire is extinguished, ventilate the compartment overboard at the highest possible rate allowed by established crew procedures for your particular aircraft to Tid the cabin and flight deck of hazardous gases and smoke. Stay alert when increasing airflow, if the fire is not completely extinguished or smoldering, increasing airflow could promote fire growth. (2) Small aircraft lack some of the safety advantages available to large transport category aircraft. Large aircraft with small vo lume occupied spaces (flight decks) have a forced venti lation system, availability of supplemental oxygen (quick donning oxygen masks), and a co pilot available. Therefore, operators of small wipressurized aircraft should open a window , if at all possible. 3. How to Prevent Hypoxia in an Unpressurized Aircraft. You can avoid life-threatening hypoxia (low oxygen) hazards that may result from the discharged halocarbon agent displacing air in unpressurized aircraft, by following the descent, ventilation, and supplemental oxygen guidance below. See the report.referenced in appendix 3, paragraph 7m oftbjs AC for infom1ation on the development of the guidance below. a. Extinguish Fire and Ventilate Cabin. As mentioned above, make sure the fire is comp letely extinguished. To rid the cabin and flight deck of hazardous gases and smoke, ventilate all unpressurized aircraft compartments overboard at the highest po ss ible rate allowed by established crew procedures for your particular a ircraft. If the fire is not complete ly extinguished, or a smolderin g fire exists, increasing airflow cou ld promote fire growth b. Descend to Lower Altitudes. 1mmediately descend at the maximum s afe rate to 8,000 ft. or to an altitude that is as low as practicable. Descending dilutes agent concentration, lowers ex p osure to agent and combustion gases, and increases oxygen concentration. We recommend descending regardless of the amount of agent u sed, the aircraft s ize , or ventilation rate . Aircraft with a maximum flying altitude of 12, 500 ft. are protected from hypoxia , without the need for supp lemental oxygen, by immediately descending as described above. c. Use Supplemental Oxygen. Use of supplemental oxygen can prevent hypoxia. Howeve r, if a supplemental diluter demand personal oxygen sys tem at CPAs above 12,500 ft., a nasal cannula up to and including 18, 000 ft CPA, or an oral-nasal mask between 18,000 ft . and 25,000 ft. CPA are u sed, th e user will not be fu ll y protected from hypoxia. This lack of protecti on is becau se the oxygen flow control for these systems is based on pressure altitude, not oxygen partial press ure. (1) Occupants flying at altitudes above 12,500 ft. should immediately switch their masks or na sal cannula to the maximum flow of oxygen, if so equipped, to get additional protecti on during the time it would take to exchange the air in the compartment three times . 16 01 / 14/ll AC 20-420 (2) Fingertip probe oxygen sensors shou ld be used with oxygen systems on unpressurized aircraft with maximum flying altitudes above 12,500 ft. These devices provide user feedback on the effects of hypoxia after halocarbon agent discharge such that the wearer can in crease the oxygen flow to their breathing device to compensate for the hypoxi a. (3) Unpressurized aircraft are allowed to use nasal cannula supplementary oxygen systems up to 18,000 ft. altitude. These systems provide no protection to a wearer when he or she breaths through the mouth, which can occur at times of stress. 4. What are the Guidelines on the Selection of Halocarbon Ex tinguishers? a. Extinguisher Performance. Primary considerati on in selecting a fire extinguisher should be performance. size, and weight (see appendix 4, paragraph 3 of this A C), hardware configuration, extinguisher throw range (see appendix 4, paragraph 1 of this AC), ease of use for novices, commercial availabHityofthe agent, and environmental issues (ODP and GWP). Special considerarion needs to be made for cold temperature operation~ as noted in chapter 3, paragraph 5b of this AC. Agent physicaJ and chem ical propertjes may also be considered. b. Toxicity/Human Ex11osure. As m en tioned previously, human exposure to halocarbon agents is a concern and needs to be addressed as noted in paragraph 2b above. However, it is far less of a concern than the consequences of an unextinguished in-flight fire. From a hazardous exposure perspective, you may elect to select a halocarbon hand extinguisher using the safe-u se WN guidance (based on perfect mixing) described below for yo ur specific compartment size. Safe-use WN guidance provides an object1ve scientific evaluation of the currently approved agents. ( I) The exposure hazard presented by the decomposition products of the agent may be considered when choosing a fire extinguisher for a particular installation. (2) Safe-use W/V guidance for various air change times, assuming perfect mixing, is presented in appendix 4, paragraph 2 of this AC. The methodology used to develop the safe-use W/Vs of halocarbon agents and their blends was developed in the repo1t referenced in appendix 3, paragraph 7m of this AC. The safe-use W/V gu id ance is based on the discharge of the largest extinguisher in a compartm ent at 70° F at the aircraft certificated CPA. (3) These safe-use WNs may be used as general guidance and are based on perfect mixing gas concentration histories. 1bis safe-u se WN gujdance is not rigid, as there are many variables that can affect the agent concentration histories. Actual concentrations encountered by occupants may be significantly lower than would be encountered if there was perfect mixing depending on agent stratification, air distribution, air flow, and geometry of a particular aircraft/aircraft compartment and may be adjusted accordingly. {4) Agent stratification/localization within a compartment, as mentioned in paragraph 4b(3) above, will be addressed in a report to be published at the FAA Technical Center . This report w iU provide limited examples and th e method to properly adjust the safe-use concentrations for those examples. See appendix 4, paragraph 2a(4) 17 01/14/11 AC 20-42D (5) For unpressurized aircraft, you should consider safe-use guidance for the highest altitude for which the aircraft is certified. (6) The cabin is considered and referred to as a compartment. The total charge weight of the largest extinguisher divided by the compartment volume should not exceed the safe-use W IV. (7) In a _pressurized aircraft (6000 to 8,000 ft CPA), the hypoxic hazard is minimal for the safe-use concentrations for the halocarbon agents in this AC. Immediate descent is not necessary. Pressurized aircraft benefit (increased oxygen and decreased agent concentrations) only from descent to altitudes below the CPA. The worst case oxygen equivalent CPA for pressurized aircraft using the safe-use W/V guidance provided in tlus AC is 10 000 ft at 2 minutes after discharge when 8,000 ft CPA is maintained. However landing as quickly as possible is always recommended when an onboard fire is suspected. c. Relative Agent Toxicity. You may want to consider the relative toxicity of extinguishers in Figure 1 below when selecting an extinguisher. Figure 1 shows the normalized toxicities of approved 5B:C extinguishers relative to the NOAEL-based toxicity of a 5B:C Halon 121 l extinguisher. These normalized toxicities are based on exposure to neat (un-decomposed) agent u ing 3 different measures: NOAEL Safe Human Concentration and LOAEL. FigUJ·e 1. Relative Toxicity of 5 B:C Halocarbon Extinguishers [I NOAE.L Basis D Safe Human Concentration Basis BLOAELBasis 1.3 1 ..2 1.1 .. , .o 1 ~ 0.9 Ill ... ·;; N 0 .8 Cl) ... .§ 3 0.7 ill 'i (J :r 0 .6 •. 0 al 10 GI 0 .5 0~ ~! 0 .4 .!:! a: 0 .3 ~ 02 0.1 0 .0 .......,_'l, 7?o<: Agent ~ d. Minimum Safe Volume. Alternatively you may consider minimum safe volumes to make your extinguisher selection. In this case, the minimum safe volume of one extinguisher is obtained by dividing that extinguisher's charge weight by the safe-use agent WN for the appropriate altitude and entilation (See appendix 4, paragraph of this AC). 18 01/ 14/ 1 l AC 20-42D 5 . How to Safely Use Halocarbon Extinguishers in Accessible Ca rgo Compartments. a. Unsafe Concentrations of Extinguishing Agent. 14 CFR § 25.857 and§ 29.855(d) require aircraft to be designed to prevent the harmful accumulation of smoke, flame, extinguishing agent and noxious gases from entering occupied areas. Airplane Flight M anual (AFM) fire fighting procedures sho uld state that the crew member should close the Class B cargo co mpartment door after extinguishing a fire. b. When to Use Portable Protective Breathing Equipment (PBE). Portab le PBE should be worn before entering the cargo compartment and at tempting to extinguish a fire, as outlin ed in 14 CF R § 25. l4 39. Note that AFM and/or Crew Operations Manual are required to have the appropriate procedure including calling out the u se of po rtable PBE and other emergency equipment necessary to fight a fire. c. Compartme nts U nder 200 Cubic Feet. Halon replacement extinguishers should have a minimum fireratingc]assification ofU .S. - UL2A:108:C fo r accessi ble Class B cargo compartments, combination passenger/cargo (combi) and cargo airplane/rotorcraft. The fire threat fo r accessible cargo compartments is primarily from Class A fires. Usually, one extinguis her with a U.S. - UL 2A:1 0 B :C rating is sufficient to fight mo st fi res li kely to occur. (1) Multiple hand-held fire extinguishers may be shared to comp ly with the cabin and accessible Cl ass B cargo compartment regul a ti ons, if they are located where a person fighting a fire in the compartment could quickly retrieve them and continue fighting the fire with minimal del ay between the discharges. It must be demonstrated that the extinguishers, as installed, can extinguish 2A and J OB:C rated fires. The combined rating is to be de tenn in ed by perfonnfog the UL 71I fire tests by discharging the extinguish ers with a delay between the end of each extinguisher 's di sc harge and the start of the discharge o f the next extinguish er based on the location of each extinguis her and an assess ment of factors such as: (a) The manp ower availabl e to fight the fire. l f two trained crew members are available to fight the fire, it may be possibl e to avoid a delay be twee n di scharges of th e extinguishers. (b) The time to recognize the completion of the discharge, to walk to the location of the next bottle, remove it from it's mow1ting bracket, puJl the pin, return to the cargo com partment, position the extinguisher to continue to fight the fire and initiate discharge. (2) The rating is based on UL 71 1 perfonnance tests. not agent weight, as the agent weight is not su fficient to predict perfonnance . Nozzle design, s uper pressurizahon and other factors affect perfonnance. The UL fire tests can be prefonned by the applicant or an approved test laboratory such as UL. 19 01/14/11 AC 20-42D Note: The recommended extinguisher rating of 2A: 1OB:C 1s lower than the 2A:40B:C rating in AC 20-42C. This is because the fire threat for accessible cargo compartments is primarily from Class A fires. The prior guidance in AC 20-42C was based on the need for at least a 2A rating for class A fires using a Halon 1211 extfoguisher to extinguish a fire. Halon 121 l extinguishers that have a class A rating of 2A also have a 40B:C rating. It has been detennined that a 1OB:C rating is more then adequate for the type and size of class B and C fires like] y to occur in a Class B cargo compartment. d. Compartments Over 200 Cubic Feet. Accessible cargo compartments of 200 ft3 and larger, in combination passenger/cargo and cargo aircraft/rotorcraft, should comply with the requirements of the FAA Airworthiness Directive (AD) 93-07-15. This AD specifies acceptable forms of fire protection equipment and operational procedures. The options provided include converting the compartment to meet the requirements of a Class C cargo compartment, u se of hand-held fu-e extinguishers, or the use of fire containment containers or covers, fire extinguishing systems and smoke or fire detectors. ( 1) If you elect to use hand fire extinguishers provide the fo llowing: (a) A minimum of three U.S. - UL listed Halon 1211 or its equivalent 2A:l 08:C hand held fire extinguishers (equivalent to the AD's requirement of 48 lbs. ofHalon 1211) readily available for use in the cargo compartment. (b) At least two U.S. - UL 2A (2-1 /2 gallon) listed water portable fire extinguishers, usually TSO C19 or its equivalent, adjacent to the cargo compartment entrance for use in the compartment. (c) Protective garments stored adjacent to the cargo compartment entrance. (d) Portable PBE with a minimum of 15 minutes of protective breathing, per 14 CPR§ 25. l 439(b )(5). This portable PBE should be TSO C 11 6 approved or equivalent, and be stored adjacent to the cargo compartment entrance. (2) If no extinguisher is available that meets the safe-use criteria for the aircraft/rotorcraft cabin, consider converting that cargo compartment to a class C comp artment with a built-in fire suppression system, or any other technology that would provide effective fire protection. Restrict personnel from entering the cargo compartment for the duration of the flight. 6. How to Inspect and Maintain the Band Fire Extinguisher for Continued Safe-Use. Maintain and inspect hand fire extinguishers in accordance with the manufacturer's nameplate instructions. Follow the maintenance procedures, inspections and testing specified in the applicable NFPA and U.S. - UL standards. 20 01/14/11 AC 20-42D a. Non-refillable, disposable fire extinguishers may have plastic discharge heads installed. L-Ocate this type of fire extinguisher in a safe area to assure there will be no damage to the plastic discharge heads. b. Non-refillable, disposable fire extinguishers are exempt from periodic hydrostatic testing. However, replace these extinguishers with a serviceable unit upon reaching: (l) The service life where hydrostatic testing would nonnally be required for a similar extinguisher, or (2) The service life guidelines established by the manufacturer if sooner. c. Recommended procedures fo r the inspection, hydrostatic test and life limits of pressure cylinders are outlined in: ( l) Speci flcation of cylinders is in 49 CFR, part 178, subpart C. (2) In spection and maintenance of cylinders is in 49 CFR, part 180, subpart B. (3) Fire extinguishers are addressed in 49 CFR § 173.309 and in 29 CFR § 1910.157. d. Manufacturers of fire extinguishers containing halon rep lacement agents approved for use on FAA certified aircraft shouJd take immediate action through the appropriate cbannel(s) to have their retest requirements included in the aforementioned regulatory guidelines. 21 01/ 14/ ll AC 20-42D Chapter 5. Locating and Mounting Hand Fire Extinguishers 1. Where to Locate and Mo unt Hand Fire Extinguishers in Passenger Compartments. lnstaJI fire extinguishers in passenger compartments according to 14 CFR §§ 23.851, 25.851, and 29 .853 and the following criteria: a. Locate hand fire extinguishers adjacent to hazardous areas (for example, galleys, accessible baggage or cargo compartments, electrical equipment racks, et'c.) to be protected. b. 1f there are no defined hazardous areas, locate the hand fire extinguishers as follows: (I) When one extinguisher is used , locate it at the flight attendant's station. (2) When no flight attendant is required, locate the extinguisher at the passenger entrance door. (3) When two or more extinguishers are used, locate one at each end of the passenger compartment and space the remainder unifonnly within the cabin area. c. Mount hand fire extinguishers for ready accessibility. ff they are not visible in their mounted position. use a placard to indicate their location. (I) Aircraft structure and mounting brackets are required to withstand the applicable inertia forces required in 14 CFR §§ 23.561, 25.561,27.56 1, and 29.561, with the hand fire extinguis her installed. Replacement of halon extinguishers with halocarbon extinguishers will require an evaluation of the mounting system strength. The mounting structure may need to be strengthened. Halocarbon clean agent extinguishers of the same listing can be 2-3 times the weight of the halon extinguishers they arc replacing. (2) For large transport category aircraft, installation of an extinguisher should include vertical reach combined with horizontal (offset) reach to ensure ease of retrieval from overhead compartments. The vertical reach should not exceed 74.5 in. ( 189.23 cm) combined with an offset reach of7.87 in. (20cm) to permit a 5 percentile female, 60.5 in. (153.67 cm.) tall to quickly access the extinguisher. Consideration shou ld be allowed for assist steps (or seats) or other factors. (3) Add the weight of the hand fire extinguisher and its mounting bracket to the aircraft empty weight and a compute a new empty weight center of gravity. d. Consider the type of fire hazard (Class A, B , C or D) ex pected to be encountered when you select a band fire extinguisher. If extinguishers intended for different classes of fire are grouped together, consider marking their intended use conspicuously via a placard or other means (near the extinguisher) to aid in the choice of the proper extinguisher at the time of the fire. 22 01/)4/11 AC 20-420 2. How to Locate and l\1ount Band Fire Extinguishers in Flight Deck Co mpartments. Consider us ing the fo ll owing criteria if you install a fire extinguisher in the flight deck compartment: a. Each hand fire extinguisher should be conveniently located, readily accessible, and it's location obvious. b. Hand fire extinguishers should be mounted for easy relea se and removal. For aircraft designed for single pilot operation, the hand fire extinguisher should be located for release and removal by lhe pilot in the seated position. (1) Secure the extinguisher(s) in mounting bracket(s) such that it requires a deliberate action t'o release the extinguisher from its primary restraint for removal from its mounting. Desibrn the mounting bracket so that upon release from their primary restraint, the extinguisher remains in position until removed from its mounting by the user. (2) Aircraft structure and extinguisher mounting brackets must be capable of withstanding the inertia forces specified in paragraph le above. c. Fire extinguishers for the flight deck compartment should be able lo extinguish Class B and C fires. 3. How to Locate and Mount Hand Fire Extinguishers in Small Single Engine and MuJtiengine Aircraft. a. Locate hand tire extinguishers so that they are easily accessible to the flight crew and the p assengers. b. Do not allow hand fire extinguishers to Lie loose on shelves, seat back po cke ts o.r seats. Properly mount the hand fire extinguisher to the airframe structure. c. Aircraf\ structure and extinguisher mounting brackets should be capable of withstanding the inertia forces specified in paragraph Jc above. 4. How Many Band Extinguishers Must I Install? a,. Transport Category Airp lanes. 14 CFR §§ 25.85 1(a) and 12 l.309{c) requires a minimum numb er of hand extinguishers to be installed on transport category airplanes. (I) The minimum number of hand fire extinguishers that must be conveniently located and evenly distributed in passenger compartments are as shown in Figure 2 below. 23 01/14/1 C20-42D Figure 2. linimu.m · umber of Hand i e Extingui hers Re uired for Transport Category ·rcraft Pa eng r ompartments Passenger o.of Capacity xtin ui her 7 through 30 1 3 1 through 60 2 61 through 200 3 20 1 through 300 4 3 1 through 400 5 4 1 through 500 6 501 through 600 7 601 through 700 2 A Jea t ne hand fire e tingui h r mu t b c n eniently I cated in the pilot c mpartm nt. ( At lea one readily accessibJe hand fir extingui her mu t be a ailable for use in ach la, A or Cla · B argo or baggage compartment and in each Cla E cargo or baggage c mpartment that j a ce ible to crewmembers i11 flight, p r 14 FR § 25.851 a)(3 . (4) At I a tone of the required fire extingui her located in the passenger compartm nt fan airp lan e with a passenger capacity fat least 31 and not more than 60, and at least Lw of th fire extingui hers located in the passenger c mpartment of an airplane with a pa enger apacity f 61 or more must ontain Halon 121 l, r equivalent, a the extinguishing ag nt. 5) TI1e quantity of extinguishing agent u ed in each extinguisher required by this e tion mu t be appropriat for the kind of fires likely t occur wh re u ed. b. ran port ategory Rotorcraft. Title 14 CPR 29.853 require a minimum numb e r fhand extingui hers to be installed in pa eng r mpartm nt : ( 1 ee Figure below for the minimum numb r hand fir e tinguisbers that mu t be n eniently I ca ed in passenger com artm nt . 24 0 1/14/ll AC 20-420 •igure 3. Minimum umber of Hand Fire E ·tin ui he Reqllired for ran port Category Rotorcraft Pa eoger ompartments Passenger o.of Capacity Extingui shers 7 through 30 l 3 1 through 60 2 61 or more 3 (2) here must be a hand fire extingui her r the flight crewmembers. 3) There are no requirement for extingu i bing systems r hand extinguishers for ac es i le cargo r baggage compartments in transport category rot rcraft. U e the hand e tingui her guidanc provided in chapter 4, paragraph 6 of thi AC for the e compartments. c. mall Airplane . Title 14 CFR §§ 2 .851 and 9 l.513(c) require a minimum mrrn f hand extinguishers to be installed on mall part 23 airplanes. At le t ne hand fire extingui her mu t b l cated within ea y acce s of the at pil t. (2 At lea tone hand fire extinguisl1er mu t e in th pas enger compartment of an airplane th t ace mmodate m re than ix pas enger . The extinguisher must minimize the hazar t xic gas c ncentration. 25 01/14/11 14 CFR AC ACO AD AFM ASTM CAA CFR CPA DOT EPA FAA FAATC FC FCOM FlC FK FM HCFC HF HFC JCA ISO LOAEL MF MPS NOAEL NFPA PFC PBE PBPK PDA PED RGL RTCA SAE SNAP ,:, Tau TSO UL USCG WN %v/v Appendix 1. List of Acronyms Title 14. Code of Federal Regulations Advisory Circular Aircraft Certification Office Airworthiness Directive Airplane Flight Manual American Society of Testing and Materials Civ il AviationAutb ority Code of Federal Regulations Cabin Pressure Altitude Department of Transportation U.S. Environmental Protection Agency Federal Aviation Administration FAA Technical Center Flu orocarbon Flight Crew Operations Manual Fluoroiodocarbon Fluoroketone Factory Mutual Research Corp. Hydrochlorofluorocarbon Hydrogen Flouride H yd rotluorocarbon Instructions for Continued Airworthiness International Organization for Standardization Lowest Observable Adverse Effect Level Multiplication Factor Minimum Performance Standard No Observable Adverse Effect Level Natio nal Fire Protection Association Perfluorocarbon Protective Breathing Equipment Physiologically Based Pharmacok.inetic Personal Digital Assistant Portable Electronic Device Regulatory Guidance Library Radio Technical Corporation of America Society of Automotive Engineers Significant New Alternatives Policy Air Change Time Technical Standard Order Underwriters Laboratories United States Coast Guard Weight per Unit Volume (WN) Ratio Volume Percent Al-1 AC20-42D Appendix 1 0Ul4/ ll AC 20-42D AppendL~ 2 Appendix 2. Definitions and Terms The following definitions and terms apply when following th e procedures outlined in this AC: 1. Air C han ge Time, -r. is U1e time in minutes, it takes for the inflow of fresh air into a compartment, with a volume equivalent to the vo lume of the compartment. 2. Cabin Pressure Altitude is specified for transport aircraft by regulation to be the air pressure in the cabin or compartment of a commercial airliner and it must not be lower than that found al an altitude of 8,000 ft (2,438 m ) under nonnaJ operating conditions, per § 25.84l(a) 3. Cargo Aircraft are aircraft configured solely to carry cargo and no personnel other than the flight crew and any additional crew required for the care of the cargo. 4. C lean Agent is electrically nonconducting, vo latUe or gaseous fire extinguishant that does not leave a residue upon evaporation. The word agem as used in this circular means clean agent unless otherwise indicated. 5. Co rnbi Aircraft are designed/configured to transport both passengers and cargo on the same level within the fuselage. 6. Compartme nt is an enclosed space on an aircraft. Examples of compartments are a flight deck, a crew rest, and a cabin. The aircraft cabin is co nsidered one compartment. 7. Dry C he mical is a mixture of finely divided solid particles, usually sodium bicarbonate, pota~sium bicarbonate, or ammonium phosphate-based with added particulate material supplemented by special treatment to provide resistance to packing, and moisture absorption (caki ng) and to promote proper tlow characteristics. 8. Dry Powder is solid materials in powder granul ar fon n designed to extinguish class D combustible metal fires by crusting, smo thering, or heat transferring means. 9. F light Crew are responsible for the operation and management of the aircraft flight controls, engines, and systems, including, but not limited to, pilot in command (captain), first officer (copilot), second officer (Hight engineer). J0. Flight Deck is the compartment of the aircraft arranged for use by the flight crew in operati ng the aircraft. 11 . Galley is the area of the aircraft for storing, refrigerating, heating and dispensing of food and beverages. A2-1 10/XX/10 AC 20-42D Appendix 2 12 . Halocarbon Agent is comprised primarily of one or mo re organic compounds containing one or more of the elements fluorine, chlorine, bromine, or iodine. Halocarbon agents are electrically non-conducting, volatile liquids. or gaseous fire extinguishants. As "clean agents", they do not leave a residue on evaporation. Halocarbon agents (hal ons and halon replacements) that are currently commercialized include the hydrochlorofluorocarbons (HCFC s), perfluorocarbons (FCs or PF Cs), hydrofluorocarbons (HFCs), tluoroiodocarbons (FlCs), and fluoroketones (FK.s), as we ll as the completely halogenated halocarbons (halons). Halocarbon agents are multipurpose class A , B, Crated agents and are most effective on Class Band C fires. Advantages of halocarbon agents include low cold shock characteri stics on electroni c equipment, no degradation of visual acuity, and low pressure. 13. Halocarbon Blend is a mixture of2 or more halocarbon agents in a portable extinguisher. 14. Halon is a short derivation for "h alogenated hydrocarbon." The chemical structure is identified as a fo ur digit number representing, respectively, the number of carbon, -fluorine, c hJ orine, and bromine atoms present in one molecule. Both Halon 12 11 and Halon 1301 are liquefied gases and typified as "clean agents." Halons primarily extin guish fire by chemically interrupting the combustion chain reaction rather than by heat removal or physically smothering. 15. Halon Equival ent Extinguisher is an extinguisher containing a clean agent which meets the MPS for hand-he ld fire extinguishers (see appendix 3 reference paragraph 7s of this AC). Equivalency does not refer to agent we ight, but the effectiveness of extinguishing a fire. Halon replacement extinguishers may be more than twice the weight of halon extinguishers. 16. Halon 1211 has the chemical name brom ochlorodifluoromethane, CBrCl F2. Halon 1211 is a mu ltipurpose, Class A, 8 , Crated agent effective against flammable liquid fires. Due to its relatively hi gh boiling point of +26°F (-4°C}, Halon 1211 discharges as an 85 percent liquid stream offering a lo ng agent throw range. J7 . Halon 1301 has the chemical name bromotritluoromethane, CBrF 3. Halon 1301 is recognized as a multipurpose agent having Class A, B, C capability in total flooding systems. However, Halon 1301 offers limited Class A capability when used in portable fire extinguishers. 1l1e boiling point for this agent is -72°F (-57.8°C). Halon 130 1 di sc harges as a gas. J8. Halon Replacement Agents are any clean agents which can be either a non-halon (halocarbon agent) or halon alternative (all other substitute agents) that have SNAP approval by the U.S. EPA and meet the MPS for band fire extinguishers. 19. Hand Fire Ex tinguisher is an approved, aircraft portable fi re extinguisher which can be used by aircraft occupants to combat accessible, incipient, on-board fues. 21. B FC-227ea is an extinguishing agent that is comprised of the chemical I, 1,1,2,3,3,3 heptafluoropropane (CF3CHFCF 3 ). The boiling point of the agent is 2.5°F (-l6.4°C). Due to this boiling point, HFC-227ea is discharged as a mixed liquid and vapor stream which readily evaporates. lt is a multipurpose agent with class A, B and C capability. A2-2 01/14/ 11 AC 20-42 D Appendix 2 22. HFC-236fa is an extinguishing agent that is comprised of the chemical 1, 1, 1,3,3,3 hexatluoropropane (CP3CH 2C F3). The boiling poinl of lhe agent is +29.5°F (-1.4°C). Du e to its relatively high boiling poinl, HFC-236fa discharges predominately as a liqu id stream which readily evaporates. It is a multipurpose agent wilb class A, Band C capability. 23. HCFC Blend 8 is an ex tinguishing agent that is a tertiary blend compri sed primarily of the ch emical 2,2-dichloro-1. l, 1-trifluoroetbane HCFC-123, (CF 3 CH Ch). Two inert gases are blended with the HCFC-123 to enhance flow distribution and fire extinguishing performance. The boiling point of the blend is 80.6°F (27°C). Due to its high boiling point, HCFC Blend B discharges primarily as a liquid stream which readi ly evaporates. It is a multipurpose agent with class A, B, and C capabili ty. 24. Labeled equipment or materials have an attached label, symbol, or o th er identifying mark of an organization that is acceptable to the authority h av ing jurisdiction and conce rned with product evaluati on that maintains periodic inspection of production of labeled equipment or materials, and by wh ose labeling th e manufacturer indicates compliance with appropriate standards or performance in a spec ified manner. 25. Listed refers to equipment materials or services included in a li st published by an organization that is acceptab le to the authority h avingj urisctiction and con cerned with eva luation of products or services. The organization maintains periodic inspection of production of listed equipment or materials or periodic evalu at ion of serv ices, and who's li sting stat es that the equipmen t, material or se rvice meets appropriate designated standards or has been tested and found suitable for a specified purpose. 26. Listing Mark is a certification mark allowed to be carried as a stamp of approval by nationally recognized standards/testing organization. 27. Lithium Ion Battery is a rechargeable battery that bas an anode made from a metal oxide comp osite containing lithium ion, and a cathode made from a specialized carbon m aterial. C harge and di sc harge of the battery is facilitated by lhe movement ofJithium ions in electrolytic so lutions. Lithjum ion batteries are used in small electronic devices such as pagers, portable computers, camco rders, and portable telephones . 28. Lithium Primary Battery is a rechargeable battery that has a lithium a.node and a cathode system consisting of carbon and either th.i onyl chloride or sulfuryl chloride. 29. Lowest Observable Adverse Effect Level (LOAEL ) is the lowest concentration at which an adverse physiological or toxicological effect has been observed in dogs. 30. Maximum Cer tificated Occupant Capacity is the maximwn number of persons that can be carried for each specific aircraft mode] as certified by the authority havingjurisdiction. Al-3 01/14/11 AC 20-42D Appendix2 31. Minimum Performance Standard (MPS) for Hand Extinguishers refers specifica1lyto two tests that hand extinguishers containing halon replacement agents must pass. See appendix 3 reference paragraph 7s. These fire tests demonstrate equivalent fire extinguishing performance currently used in aircraft and assess the toxicity of the decomposition products. 32. Minimum Safe Volume refers to the smallest compartment vol ume into w hi ch one extinguisher could be discharged, assuming perfect mixing of agent, without posing a toxicity hazard. Minimum safe vol um es are dependent on the age nt, the agent weight, ventilatio n, and press ure altitude of the discharge. 33. Neat jn this context refers to un-decomposed agent. 34. No Observable Adverse Effect Level (NOAEL) is the highest con centration at which no adverse physiological or toxico logical effect ha s been observed in dogs. 35. Ph ysiologically Based Pbarmacokinetic (PBPK) Model is a mathematical mod el for human health risk assessment md investigation of toxicity. The health concern for halocarboa.s, including baJons, is cardiac sensitization wrucb occurs at a fixed target arterial co ncentration. The model estimates the allowabl e arterial blood concentration as a functio n of agent exposure time to establish both the concentration of agent and duration to which personnel co uld be safely exposed. The PBPK modeling is endorsed by the U.S. EPA and the NFP A. 36. Rated/Rating is a numerical value assigned to an extinguish er based on it s fire extinguishfog capability. 37. Safe Human Exposure Concentrations are based on PBPK modeling. Safe human conce ntrat ions are exceeded when the simulated arterial concentration exceeds th e target arterial concentration. 38. Small Aircraft are defined by part 23. 39 . SNAP Program is EPA 's significant new alternatives policy (SNAP) program to evaluate and regulate substitutes for ozone depleting chemicals that are being phased out under the s tratospheric ozone protection provisjons of the Clean Air Act. 40. Time of UsefuJ Consciousness is the time available to don an oxygen mask with out assistance. 41. Unventilated Compartment for the purpo ses of the AC is a compartment where the air change time is not known or exceeds 6 minutes. 42. Ventilated Compartment is a compartment wh ere the air change time is known and does not exceed 6 minutes. 43. Volume Percent (% v/v) is the gas volume in liters per 100 liters of the resulting gas mixture, e.g. 2% v/v Halon 12 11 mixture contains 2 liters Halon 121 1 per 100 liters volume. Al-4 01/14/ 11 AC 20-42D Appendix 3 Appendix 3. Related Publications and How to Get Them l. Code of Federal Regulations (CFR). You can get copies of Title 14 , 40, 46, and 49 of the Code of Federal Regulations, parts from the Superintendent of Documents, Government Printing Office, P.O. Box 37 154, Pittsburgh, PA 15250-7954. Telephone (202) 512-1800; fax (202) 512 2250. You can order copies Title 14 through the FAA website at http://rgl.faa.gov/. Select "Access" then ''Online Bookstore." Select "Avi at ion;' then "Code of Federal Regulations." You can also get copies of 14 CFR sections on-line at www.gpuaccess.gov/ cfr/ and copies of 40 CFR sections on-llne at www.epa.gov/epahome/cfr40.htm. The fo llowing is a list of applicable Federal Regulations used for this AC: a. 14 CFR §§ 2 1.305, 23.561, 23.851, 23.1441 , 23. l443-1449, 25.56 1, 25.851, 25.857, 25. 1439, 27.56], 27.861, 29.561, 29.851, 29.853(e) and (f), 91.122, 91.211, 91.193, 121.309(c). 125.1 19(b) and(c), 127.107(c), 135.155. b. Title 40 of the Code of Federal Regulations (40 CFR), Chapter 1--EnvironmentaJ Protection Agency, part 82-Protectioo of Stratospheric Ozone, subpart G-Significant New Alternatives Policy Program and subpart H~Halon Emjss ions Reduction (40 CFR part 82). c. Title 46 of the Code of Federal Regulations ( 46 CFR), Chapter I-Coast Guard1 Department of Transportation, paL1 34-Fire Fighting Equipment. d. Title 49 of the Code of Federal Regulations ( 49 CFR), Transportation. 2. FAA Ainvorthiness Directive (AD). You can get copies of the following AD from the FAA 's website at W\.\ \\ .a 11web .taa.go\'1rgl. a. AD 93-07-15, Boeing And McDonnell Douglas Models 707, 727, 737,747, and 757 and McDonnell Douglas Models DC-8, DC-9, and DC-LO Series Airplanes 3. FAA Advisory Circ uJars (AC). Order copies of AdVlsory Circulars (AC) from the U.S. Department of Transportation, Subsequent Distribution Office, M-30 , Ardmore East Business Center, 3341 Q 75th Avenue, Landover, MD 20795. Telephone (301) 322-5377, fax (30 1} 386 53 94. To be placed on F AA's mailing Iist for free A Cs contact, U.S. Department of Transportation, Distribution Requirements, Section, M-494.1 , Washington, D.C. 20590. You can also gel copies at www.air web faa.uO\ ' rg.l. On the website, select ..Advisory Circulars,'' then select '' By Number." a. AC I 20~80, In-Flight FiTes b. AC 20-42C. Hand Fire Extinguishers for Use in Aircraft c. AC 25-17. Transport Airplane Cabin Interiors Craslzworrhiness Handbook d. AC 25-18, Transport Catego,y A irp/anes Modified for Cargo Service A3-J 01 / 14/ 11 AC20-42D Appendix 3 e. AC 25-22, Certffication o.f Transport Ai1plane Mechanical Systems f. AC 25-869-1 , Fire Protection Systems g. AC 65-9A, [Large AC} Airframe and Powe,plant Mechanics General Handbook h. AC 65-12A, [Large AC} Ai,:fi·ame and Powerp lant Mechanics Powe,plan t Handbook 4. FAA Technical Standard Order ([SO). You can find the fo ll owing technical standard orders on the FAA website at htlp: //rgJJaa.gov/ or at www.airweb.faa.gov/rgl. You will also find the TSO lnd ex of Articles at the same site. a. TSO-CJ 9, Portable Water-Solution Type Fire Extinguisher b. TSO-Cl 16 Crewmember Portable Protective Bre athing Equipment 5. FAA Safety Alerts for Operators (SAFOS) and Information for Operators (lnFOs) a. SAFO 09013 Fighting Fires Caused by Lithium Type Batteries in Portable Electronic Devices, June 23, 2009, www .faa.uov/other visiUaviation industrvlairlinc o peralors/airline safety/snfo/all safos/media/ 2009/ SAFO09013.pdf b. InFO 09010 Availability of a Federal Aviation Administration (FAA) [n-flight Firefighting Training Vi deo, June 23 , 2009, www.faa.gov/ other visil/avialion industry/airline operators/air li ne safetyfmfo/all infos/media/ 2009/in fo090 I O.pd f 6. FAA Training Videos: a. "Extinguishing in-flight Laptop Co mput er Fires" and " Cabin Crew F irefighting Training Video ," a training video on the use of hand extinguishers to fight on-board fires are available for vie wing at www.fire.tc. fa .a.gov/2007Conference/session details.asp?sessionLD=26 7. Reports and Papers. Order copies of the following reports and papers from the National Technical Tnformation Service, Springfield, Va. 2216 L FAA publications c an also be found on the following Web S it e of the F AA Fi.re Safety Branch: http://www.fire.tc.faa .r.mv/repo1is/reports.asp. Journal articles can be obtained di rectly from the publisher. Printed copies of Civil Aviation Authority documents are available from Documedia Solutions Ltd. , 37 Windsor Street, Cheltenham, Glos., GL522DG, United Kingdom. a. Abramowitz, A., Neese. W., S lu sher, G, Smoke and Extinguisher Agent Dissipation in a Small Pr essurized Fuselage, Federal A viation Administration, Repo rtNo. DOT/FAA/CT 89/3 1, 1990. A3-2 01/14/11 AC 20-42D Appendix 3 b. Blake, D.R., Effectiveness ofFlight Attendants Attempting to Extinguish Fires in an Accessible Cargo Compartment, Federal Aviation Administration Technical Note DOT/FAA/AR-TN99/ 29 , 1999. c. Chattaway,A., The Development ofA Hidden Fire Test for Aircraft Hand Extinguisher Applications, Civil Aviation A uthority Paper No. 95013, London, 1995. d. Cherry, R.G. W. et al, A benefit Analysis.for Enhanced Protection.fi·om Fires in Hidden Areas on Transport Aircraft, Federal Aviation Administration Report No . DOT/ FAA/AR - 02 /50, CAA Paper 2002/01. e. Colton, B., Gargas, M., Sweeney, L., "Setting Acute Exposure Limits for the Halotton 1 Clean Agent Onboard Aircraft Using PhysiologicalJy Based Pharmacokinetic Modeling, Submitted to Louise Speitel, Federal Aviation Administration, July 16, 2008. f. Eklund, Thor T.1 Analysis of Dissipation of Gaseous Extinguishing Agents in Ventilated Compa rtments, Federal Aviation Administration Report No. DOT/ FANCT -83/ 1, 1993. g. Hill, R.G., and Speitel, L., In - Flight Aircraft Seat Fire Extinguishing Tests (Cabin Hazard Meas1,1rement, Federal Aviation Administration Report No. DOT/FAA/CT-82/111, D ecember 1982. h. Krasner, L.M., Study of Hand-held Fire Extinguishers aboard Civil Aviation Aircr~fi, Factory Mutual Research Corporation, Federal Aviation Administration Report No . DOT/ FAA/ CT-82 / 42, 1982. i. Lain, M .J.,Teagle, D .A., Cullen, J.1 Dass,V., Dealing with In-Flight Lithium Battery Fires in Portable Electronic Devices, Civil Aviation Authority Paper No. 2003/4 , London, 2003 , © Civil Aviation Authority 2003. j. Sl usher , G.R. , Wright, J.A., and Speitel1 L.C., Halon Extinguishment of Small Aircraftlnstrument Pan el Fires, DOT/ FAA/CT -86/ 26 , December 1986. k. Slusher, Gera ld R .. Wrigllt, Joseph, Demaree, James, Halon E.xlinguisher Agent Behavior in a Ventilated Small Aircraft,, Federal Aviation Administration Report No . DOT/ FAA/CT- 86 /5 , 1986. l. Slusher, G.R., Wright, J .~ Demaree , J.E., Neese, W.E .. Extinguisher Agent Behavior in a Vantilated Small Aircraft. Federal Aviation Administration Report No. DOT/FAAJCT 83/30, 1984. m. Speitel, Louise C., Lyon, Richard E., Guidelines.for Safe Use of Gaseous Halo carbon Extinguishing Agents in Aircraft, Federal Aviation Administration: Report No. DOTIFAA/AR 08/3. A3-3 01 / 14/ 11 AC 20- 42D Appendix 3 n. Tabscot1. R.E. and Speitel, L.C. eds., "Options lo the Use ofHalons for Aircraft Fire Protection Systems- 2002 Update'', Federal Aviation Administration Report No. DOT/FAA/AR 99/63, Task Group on Ha lon Options, International Halon Replacement Working Group, U.S. Department of T ransportation, FAA William J. Hughes Technical Center, February. 2002. o. Vinegar, A., Jepson. G.W. and Overton, J.H (1998). PBPK Modeling of Short-term (0-5 min) Human Inhalation Exposures to Halogena ted f~ydrocarbons, Inhalation Toxi co logy. 10:411-429. p. Vinegar, A., Jepson. G.W ., Cisneros, M., Rubenstein, R. and Brock, W.J. (2000), Setting Sqfe Acute Exposure Limits/or Halon Replacement Chemicals Using Physiologically Based Pharmacokinetic Modeling, Inhalation Toxicology, 12:75 1-763. q. Vinegar, A (2001), .Nfodeling Cardiac Sensitization Potential o/ Hwnans Exposed to Halon 130 l or Halon 1211 Aboard Aircraft, Aviation, Space and Environmental Medicin e, Vol. 72, No. 10. r. Vi negar, A., Jepson. G.W., Hammann~ S.J., Harper. G., Dierdorf. D.S. and Overton. J.H .(1999), Simulated Blood Levels o.fCFJI. in Per so nnel Exposed During Its Release from an F-15 Jet Engine Nacelle and During Intentional /11/talati on, AIHA Journal, 60:403-408. s. Webster, Harry, De,,elopmenl ofa Min imum Performan ce Standard (MPS) for Hal!d- Held Fire Extinguishers as a replaceme nt for Halon 1211 on Civilian Transport Category Ai rcrafi, Federal Aviation Administration Report No . DOT/FAA/AR-01/3 7, 2002. t. Webster, Harry, Flammability Assessment oj Bulk- Packed, Noncha rgeable, Lithium Prima,y Batteries in Transport Catego,y Aircra:fi, Federal Aviation Administration Rep ort No. DO T/ FANAR-04/26, 2 004 . u. Webst er , Harry, Flammability Assessment ofBulk- Packed, Rechargeable, Lithium /on Ce l/_s in Transport Categ01y Aircraft. Federal Avia ti on Administration Report No. DOT/FAA/AR-06/38, 2006. 8. American Society of Testing and Materia ls (ASTM) Standards. You can get copies of the fo ll owing ASTM standards from ASTM Internati ona l, 100 B arr Harb or Drive, PO Box_ C700 , West Conshohocken. PA 19428-2959. Telephone (6 10) 832-9585. You can also ord er on-line at wv.-w.as tm .org . or contact ASTM Customer Service at se rvice(ft!astm.org. a. ASTM D7673- l 0. S1andard Specification/or Halon 1211, Bromochlorodifl1wromethane (CP2CIBr) b. ASTM D5632-08. Standard Spe cification/or Halon 1301, Bromotrijluorom ethane /CF3 81 ) c. ASTM D5631-08. Standard Pra cti ce for Handling. Transportation and Storage of Halon J3Ul, Bromotrifluoromethane (CFJBr) A3-4 01/14/11 AC20-42D Appendix 3 d. ASTM D 7122-05, Standard Spec~fication for HCFC Blend B (CF3CCl2H. Ar. and e. ASTM D 7123-04, Standard Practice/or Handling, Transportation, and Storage of HCFC Blend B (CF3CCl1H, Ar, and CF4) f. ASTM 6064-03, Standard Specification/or HFC-227ea l,1,1.2,3.3,3 Hepta.fluoropropane (CF:1 CT-IFCF1) g. ASTM D6065-05, Standard Pracricefor Handling. Transportation, and Storage of HFC-227ea 1, I, 1,2.3,3,3 -Heptajluoropropane (CF3CHFCF3) h. ASTM D6541-05, Standard Specification for HFC- 236/a. 1,1. 1,3,3,3 l lexafluoropropane {CF3CH2CF3) i. ASTM D6427-04. Sta ndard Practice/or Handling, Transportation, and Storage of HFC-236/a, l,1,1,3.3,3-Hexafluoropropane (CF3CH2CF3) 9. Factory Mutual Research Corp. (FM). Order copies of the FM approval standards from FM Co rporate Headquarters 1151 Boston-Providence Turnpike, P.O. Box 9102, Norwood, MA 02062 USA. Telephone+ 1-781-762-4300. You can also order on-line at www . finglobal.com: 10. International Organization for Standardization (ISO). Order copies of th e following ISO standards from TSO, 1, rue de Varembe, Case postale 56, CH-1211, Geneva 20, Switzerland. Telephone +41-22-749-01- 1 l. You can also order on-line at www.i ~o .org: a. ISO 720 1-1: 1989, Fire Protection -- Fire Extinguishing Media -- Halogenated f(vdrocarbons -- Part I : Spec(lica.tionsfor Halon 1211 and Halon I 301. J 1. National Fire Protection Association (NFPA). Order copies of the followingNFPA standards from NFPA, I Batterymarch Park, Quincy, MA 02169-7471. Telephone + I 800 344 3555 or+ 1 617 770-3000. You can also order on-line at www .nfpa.org: a. NFPA 10, Standard fo r Portable Fire Extinguishers, 2007 Edition b. NFPA I 2A, Standard on Halon 1301 Fire Extinguishing Sys rems. 2009 Edition c. NFP A 12B, Standard on Halon 121 I Fire Extinguishing Systems, l 990 Edition (No longer an active standard) d. N FP A 200 I, Standard on Clean Agent Fire Extinguishing Systems, 2008 Edition A3-5 01/14/ 11 AC 20-42D Appcndix3 12 . R TCA In c. Documents. Order copies of the following RTCA Inc. documents from RTCA ln c., 1828 L Street NW, Suite 805. Washington, D.C. 20036. Telephone (202) 833-9339, fax (202) 833-9434. You can also order copies online at W\\,\V. nca.org. a. RTCA/DO-160F, Environmental Conditions and Test Procedures for Airborne Equipment 13. SAE Documents. Order copies of SAE Aerospace Standards from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001. Telephone (724) 776-4970, fax (724) 776-0790. You can also o rd er copies onHne at www.sac.org. 14. Underwriters Laboratories, Inc (UL), You can get copies of the following U.S. - UL standards from UL Corporate Headquarters, 333 Pfingsten Road, Northbro ok, 1L 60062-2096 USA. Telepho ne Customer Service + 1-877-ULHELPS ( l-877-854-3577). You can also or der on-line at: ,.vww .U LS Landan.l s.com . a. U.S. - UL 154, Carbon-Dio,\ideFire Extinguishers (Ninth Edition). April20, 2009. b. U.S. - UL 299. D,y Chemical Fire Extinguishers (Tenth Edition). April 20, 2009. c. U.S . - UL 626, Water Fire Extinguishers (Eighth Edition), January 31 , 2007. d. U.S. - UL 711. Rating and Fire Testing ofFire Extinguishers (Seventh Edition), Apri l 13, 2009. e. U.S . - UL I093, Standard for Haloge nated Agent Fire Extinguishers (Fifth Edition), November 30, 1995. (UL intends to withdraw this standard effective Octobe r 2014) f. U.S. - UL 2129, Halocarbon Clean Agent Fir e Extinguishers (Second Edition) • .J anuary 3 1, 2007 . A3-6 01/14/11 C 20-420 Appendix4 Appendix 4. Explanatory Material l . at Effective Throw Ranges. TypicaJ throw ranges for halocarbon and water extingui her list ed in Figure 4 bel w. Figure 4. Effective Thro\' Ran e for Halocarbon Replacement and ater Extinguisher aJon Agent Effective Throw Ranges for UUULC Rated Extinguishersa,b (ft.) 2-B:C 5-B:C 1A-10B:C 2A 2A-10B:C 2A-40B:C HCFC Blend B 6-10 9-15 9-15 N/A 12-18 NIA HFC-236fa 8-10 10-12 14-16 NIA 14-16 N/A HFC-227ea NIA 8-10 NIA N/A N/A NIA Halon 1211 9-12 9-15 12-18 N/A NIA 12-18 Halon 1301 NIA NIA NIA NIA N/A N/A Waterc NIA NIA NIA 45-55 N/A N/A a Thro'I! range i. extinguisher dep ndanl and ma d(ffer ji·om tabulated values. b Check Ih mam4aclurer 's literature for th e throw ranges of their e ·tinguishers. c Initial Throw Range 2. afe- se uidaoc . The toxicity guidanc for U1e inhalation f hal carbon apors i n ervative. The d elopment of thi guidance can e foll!ld in the r p rt re erenced in appendix 3 . paragraph 7m of this AC . The meU1 d logy u ed applies pharmacokinetic (PBPK modeling of canine bl d oncentration data t p rte t mixing agent de ay curves. A particular PBP model and target arterial con entration w u ed, a outlined in tion 4.1.2 of the aforementioned rep rt. It a ume a compartm nt temperature of 70° (21 ° ) at the stated pre sure altitude perfect mixing of the agent, and an agent weight of the larg t xtingwsher in that aircraft c mpartment. As a result. Halon 1211 safe-use concentration ' are lo wer than in the previou AC. TI1e guidance allows for adju trn.ent for ventilation I calization and agent tratification resulting in higher afe-u se concentrations. You may el eel t u afe-use W /V guidance or the minimum afe olume guidan e. B th are outlined bel \ . If used, this g nerally conservati e guidance hould prate t pa engers and crewmembe fr m neat agent lo icit . i.e. b th cardi t icity and anestheti effe t . e W/V Guidance-. n ider the following: a. Agent ( I Th total agent charge weight of the 1 rgest required e tingui hers in a ompartment divide the ompartment v lume shou ld n t e ceed the afe-use WN. 4-1 01/14/11 AC 20-42D Appendix 4 (2) Multiplication factors, MFvent1,ared • may be applied to the safe-use W/Vs found in Figure 5 be low resulting in higher safe-use agent concentrations in ventilated compartments where the air change time is known. See Figure 6 below or reference report appendix 3, paragraph 7m of this AC for the multiplication factors. These multiplication factors, referred to as the ventilation benefit in the reference report, are based on perfect mixing. Figure S. Safe-Use Agent WN for Halocarbon Extinguishers in Unventilated Passenger and Crew Compartments Agent Maximum Safe W N (lbs/fr) Sea Level (For-info only) Pressurized Aircraft (8kft. CPA) Unpressurized Aircraft 12.Sk fi. 14k ft. 18kft. 25k HCFC Blend B a 0.00499 0.003 71 0.00311 0.0344 0.00293 0.0324 0.00249 0.0275 0.00185 HFC-227ea 0 0.0551 0.0409 0.0442 0.0205 HFC-236fa a 0.0595 0.0371 0.0349 0.0297 0.0221 Halon 1211 b 0.00224 0.00166 0.00139 0.00131 0.00112 0.000829 Halon 1211 c,n 0.00449 0.00334 0.00281 0.00264 0.00225 0.00166 Halon 1301 a 0.0260 0.0193 0.0162 0.0153 0.0130 0.00968 a Values are based on afe human concentrations. See reference report appendix 3, paragraph 7m of this AC b This value is based on the NOAEL Halon 1211 concentration. of 0.5 %. c This value is based on the LOAEL Halon J_J J concentration of1. 0 %. d Safe human concentrations are n.ot available/or Halon 1211. The Halon 12 11 LOAEL concentration of 1.0% (vlv) has been shown to be safe for humans. See reference report in note a above. However. the safety.factor is smaller than that set for the other agents. Figure 6. M uJtiplication Factors (MF venlilatcd) for Ventilated Compartments Agent Air Change Time, ,. (minutes) 0.5 1.0 1.5 2.0 3.0 4.0 5.0 6.0 >6" HCFC BlcndB 2.80 2.33 2 .14 2.02 1.89 1.79 ].70 1.62 1 HFC-227ea 1.90 1.53 1.39 1.32 1.24 1.19 1.16 1.14 1 HFC-236fa l.98 1.58 1.42 1.34 1.25 l.20 l.17 1.15 1 Halon 1211b 1.96 1.57 1.42 1.34 1.25 1.21 1.17 1.15 1 Halon 1301 1.96 1.57 1.42 1.34 1.25 1.21 1.17 1.15 1 a No MF Ve n1 il 11.1ed is applied ifair change h'me is greater than 6. b .A/fore conservative MF ve111Ua1ed than actual. Based on Halon 1301 MF Ve11 11l01ed - (3) Safe-use selector curves may be used in lieu of Figure 5 and 6 above. They can be found in the reference report mentioned in paragraph 2a(2) above and can be used to obtain safe-use W N for ventilated aircraft. A4-2 01/14/ 11 AC 20-42D Appendix4 (4) Actual concentrations encountered by occupants may be significantly lower than the perfect mixing model concentrations, depending on agent stratification, air distribution, and geo metry of a particular aircraft/aircraft compartment and the height and position of the occupant. A correction ultimately may be made for stratification/localizati on which may further increase the calculated safe-use concentration. See chapter 4, paragraph 4b(3) of this AC. The FAA will publish a report with limited examples of stratification and a methodology for use in determining this correction to adjust the safe-use concentrations for those examples. This report will include a comparison of actual post-discharge halocarbon concentration histories with perfect mixing concentration histories. The safe-use concentrations can be determined from the kinetic solution of equation 6 of the report referenced in appendix 3, paragraph 7m of this AC a lon g with the target arterial concentrations and/or other calculation guidance provided in that repon. b. M1nimum Safe Volume. This gujdance may be used in place of the safe-use WN guidance. It establishes a baseline minimwn volume at which an extinguisher may safely be used , assuming perfect mixing. (1) The minimum safe volume is a useful tool for comparing the toxi city of hand extinguishers with the same fire fighting perfonnance, i.e. the same U .S. - UL rating. The lower the m.inimwn safe voJume used, the comparatively less toxic the agent. Therefore, the safest extinguisher of a given rating has the lowe st minimum safe volum e. Obtain the minimum safe vo lume of an extinguisher by d ividing the charge weight of the agent in the largest extinguisher in an aircraft compartment by the safe-u se agent WIV for the appropriate altitude and ventilation. Charg e Weight,ig~,., MinimumSaje Volum e= (;) Where, (; ) is the safe-use W/ Vobtained from Figure 5 and 6 of this AC . (2) Extinguishers in Unventilated Compartments. The minimum safe volume for unventilated aircraft should be used when the air chan ge time is unknown or exceeds 6 minutes>and when multiplicabon factors fo r ventilated airer~ MFv enti la t.eJ, are not available for a particular agent. If the safe-use WN can not be met for any of the agents, consider the relative neat agent toxicities of extinguishers in Figure 1 when selecting an extinguisher. See Figure 7 for the minimum safe volumes for extinguishers in unventilated compartments. A4-3 01/14/11 AC20-42D Appendix4 Figure 7. Minimum Safe Compartment olumc for One E tinguisher in nventilated ompartmen . Minimum Safe Volume for One S B:C Extinguisher (ft 3) Agent Sea Pressurized Agent Weighta Level Aircraft Non-Pressurized Aircraft 8 ,0 00 ft (lbs) (info 12,500 ft 14,000 ft 18,000 ft onlv) C