Advisory U.S. Department of Transportation Circular Federal Aviation Administration Subject: SMOKE DETECTION, PENETRATION, AND Date: 1/6/94 AC No: 25-9A EVACUATION TESTS AND RELATED Initiated by: ANM-110 Change:
FLIGHT MANUAL EMERGENCY PROCEDURES PURPOSE. This advisory circular (AC) provides guidelines for the conduct of certification tests relating to smoke detection, penetration, and evacuation, and to evaluate related Airplane Flight Manual (AFM) procedures.
These guidelines may be used to reduce the number of decisions based solely on judgment in conducting tests and evaluating test results. while this AC is not mandatory, it ofters a method of demonstrating compliance with the applicable airworthiness requirements. In some cases designers have chosen to design beyond what is prescribed in the airworthiness requirements. A limited discussion of the use of such designs/devices is included. This AC does not constitute a regulation and is not intended to require anything beyond that specifically required by the regulations.
2. CANCELLATION. Advisory Circular 25-9, 'Smoke Detection, Penetration, and Evacuation Tests and Related Flight Manual Emergency Procedures, dated July 29, 1986, is canceled.
3. RELATED FAR SECTIONS. The related sections of the Federal Aviation Regulations (FAR), as amended through Amendment 25-74, are as follows. Where applicable, corresponding sections of Part 4b of the Civil Air Regulations (CAR) of 1962 follow each cited Part 25 section of the FAR.
25.831/4b.371/121.219 Ventilation.
25.854/121.308 Lavatory fire protection.
25.855/4b. 382,384 Cargo or baggage compartments.
25.857/4b.383 Cargo compartment classification.
25.858 Cargo compartment fire detection systems.
25.869/25.1359/4b.626 Fire protection: systems/Electrical system fire and smoke protection.
25.1301/4b.600,601 Function and installation.
25.1309/4b.606 Equipment, systems, and installations.
25.1439/4b.380,651/121.337 Protective breathing equipment.
25.1585/4b.742 Operating procedures.
Part 25, Appendix 'F' Test Criteria and Procedures for Showing (Part 1) Compliance with § 25.853, or 25.855
121.221 Fire precaution.
. AC 25-9A 1/6/94
121.485/121.523 Flight time limitations: Three or more pilots and additional flight crewmember.
4. RELATED READING MATERIAL.
a. Advisory Circulars (AC).
AC 25-7 Flight Test Guide for Certification of Transport Category Airplanes AC 25-16 Electrical Fault and Fire Prevention and Protection AC 25-17 Transport Airplane Cabin Interiors Crashworthiness Handbook Advisory Circulars can be obtained from the U.S. Department of Transportation, M-443.2, Utilization and Storage Section, Washington, D.C. 20590.
b. Technical Standard Orders (1S0).
TSO-CIc Cargo and Baggage Compartment Smoke Detection Instruments TSO-C1le Fire Detectors (Thermal Sensing and Ionization Sensing Type) TSO-C99 Protective Breathing Equipment TSO-C116 Crewmember Protective Breathing Equipment Technical Standard Orders can be obtained from the Federal Aviation Administration (FAA), Aircraft Certification Service, Aircraft Engineering Division, Technical Analysis Branch (AIR-120), 800 Independence Ave. S.W., Washington, D.C. 20591.
c. Society of Automotive Engineers (SAE) Documents.
AS 8031 Personal Protective Devices for Toxic and Irritating Atmospheres, Air Transport Crew Members AS 8036 Fire Detection Instruments, cargo compartment AS 8047 Performance Standard for Cabin Crew Portable Protective Breathing Equipment for Use During Aircraft Emergencies Society of Automotive Engineers documents can be obtained from the SAE Inc., 400 Commonwealth Drive, Warrendale, Pennsylvania, 15096.
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1/6/94 AC 25-9A
d. Federal Aviation Administration Orders.
8110.4 Type Certification 8320.15 Implementation of Systems and Powerplant Maintenance Requirements 8110.8 Engineering Flight Test Guide for Transport Category Airplanes Federal Aviation Administration Orders can be obtained from Document Inspection Facility (Attention: APA-220), Federal Aviation Administration, 800 Independence Ave. S.W., Washington, D.C. 20591; (202) 267-3484.
e. Others.
"Fire Detector Response in Airplane Application" by Steve J.
Wiersma and Robert G. McKee of the Fire Research Department, SRI International, Menlo Park, California. This article was published in the August/September, 1978 issue of Aviation and was based on a SRi International report by N.J. Alvares and R.G. McKee titled, "The Response of Smoke Detectors to Pyrolysis and Combustion Products from Airplane Interior Materials, prepared by NASA under contract NAS2-8538. Reference was also made in this article to "Fire Detection Devices," Aviation Engineering and Maintenance, November/December, 1977.
(2) National Bureau of Standards Information Report NBSIR-77 titled "Instruction Manual for NBS Photometric Smoke Measurement System" by Richard W. Bukowski, from the Center for Fire Research, Institute for Applied Technology, National Bureau of Standards, Washington, D.C. 20234.
LIMITATIONS. The test procedures in this AC apply to smoke detection, smoke penetration, and smoke evacuation after limited duration smoke generation in cargo, storage, baggage compartments, equipment bays, equipment cooling systems, and other non-continuously occupied areas (e.g., galleys, lavatories, or crew rest areas).
Protection against continuously generated smoke in the cockpit, although not specifically required by the regulations, is provided by present smoke evacuation procedures. Present smoke evacuation testing demonstrates the ability of the smoke evacuation system to handle smoke emanating from reasonably probable continuous smoke sources.
6. BACKGROUND.
a. Part 4b of the CAR was recodified in 1965 as Part 25 of the FAR.
related policy material contained in Civil Aeronautics Manual (CAM) 4b is applicable to Part 25, as originally recodified, and to current Part 25, except in areas that have been amended since recodification.
b. The development of standardized test procedures was initiated in 1975 with the intent to eliminate subjective evaluations of the smoke detection, Par 4
penetration and evacuation procedures used in demonstrating compliance with the applicable sections of Part 25. Though the flammability potential of the interior cabin materials has been reduced since that time, these materials may emit potentially lethal smoke and toxic gases when they are exposed to sufficient heat or are involved in the combustion process. Due to these concerns by the FAA, and National Transportation Safety Board (NTSB) recommendation(s), AC 25-9 was developed and first issued in 1986.
c. This revision of the Advisory Circular (AC) addresses the following issues:
(1) Recommendation of National Academy of Sciences (NAS) Study, 1986.
(i) Subsequent to the release of the AC 25-9, the National Academy of Sciences (NAS), in compliance with Congressional action, made 19 recommendations relating to cabin air quality in their 1986 report, The fety one of there, "The recommendations was that the widespread practice of aising the cabin altitude to a maximum of 10,000 feet to aid in smoke evacuation be investigated and Procedures, Shoute be tilar fie wif respect to at evaluation proction. should be clarified with respect to smoke evacuation procedures.
(ii) The FAA contacted all the domestic transport airplane manufacturers and all foreign manufacturers of transport airplanes with U.S.
type certificates through their respective airworthiness authorities to obtain relevant smoke evacuation procedures information.
(iii) The FAA received responses from 4 foreign authorities, 2 foreign manufacturers, and 7 domestic manufacturers. The flight manual procedure to raise the cabin altitude in the event of smoke in the passenger cabin or flight deck did not apply to all airplanes and there was a variety of recommended cabin altitudes and smoke clearance procedures listed in the data received. It was clear from the data, however, that the practice of raising cabin altitude to a maximum value (below 10,000 feet) is indeed a viable and effective technique, and has been shown in numerous flight tests to lessen the concentration of smoke and hasten its removal. In all cases, the manufacturers that responded to our inquiry stated that their flight test experience supported the use of this technique. Former paragraph 5b, issued here as paragraph 8b, has been clarified accordingly.
Systems, Effective July 20, 1990. As part of a clarifying editorial change Amendment 25-72 to Part 25 of the FAR, $25.869: Fire protection:
under Amendment 25-/2, all tire protection requirements tor electrical systems (§ 25.1359), vacuum systems (§ 25.1433), and oxygen systems (§ 25.1451) were combined and transferred to subpart D, as new § 25.869, under the heading "Fire protection: systems," and Appendix 'F'. Reference to § 25.1359 in this AC has been changed to § 25.869 accordingly.
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Amendment 25-74 to Part 25 of the FAR, §25.854: Lavatory fire protection, Effective May 16, 1991. Amendment 25-74 to the FAR added B 25.854, which requires lavatory fire protection. Section 25.854(e) requires chat each lavatory must be equipped with a smoke detector system or equivalent that provides a warning light in the cockpit, or provides a warning light or audible warning in the passenger cabin that would be readily detectable by a flight attendant. The same requirement was retroactively applied under § 121.308, effective March 29, 1985, for all airplanes operating under Part Appropriate guidance material has been added in paragraphs 9 to 12 for compliance tests.
Crew Rest Area Smoke Detection Certification Tests. Crew rest areas for flight and cabin crews are generally provided in long range transport category airplanes. "Sleeping quarters are required for flightcrews whenever a pilot is scheduled to fly more than 12 hours during any 24 consecutive hours (§§ 121.485(a) and 121.523(b)). Crew rest areas may be located adjacent to the cockpit, away from the cockpit or remote (upper deck, lower lobe, etc.). Since the crew rest area may not always be occupied, a smoke detection system and equipment tor tire tighting have been required, for some of these designs, to minimize the hazards associated with a tire in the crew rest area. Guidance material developed for smoke detection in the crew rest areas is now included in this circular.
The determination of whether a smoke or fire detection system is required in crew rest areas has been developed on a case-by-case basis. In general, when the area has been located in a remote compartment, i.e., above or below the main passenger deck(s) or totally isolated by walls when on the main passenger deck(s), and is not occupied at all times from push-back to disembarking, the FAA has determined that a smoke detection system is required. The requirement has been spelled out in issue papers or special conditions. When the crew rest area is located in the main passenger cabin and is separated only by curtains, the smoke detection systems have not been required.
(5) Status of FAA Research Program on Enhanced Emergency Smoke Venting (Included here for information purposes only, not for any FAR compliance). In compliance with a commitment to Congress, the FAA has reviewed both emergency procedures and airplane ventilating systems capability for in-flight fire smoke removal from passenger cabins. The FAA, National Bureau of Standards, U.S. Air Force, Douglas, and Boeing, among others, participated in that evaluation. Further information on the status of this project and lessons learned may be obtained from:
Manager, Fire Satety Branch, AcD-240 FAA Technical Center Atlantic City International Airport, New Jersey 08405
(6) Helium Smoke Generators as Test Equipment. In 1991, engineering personnel at FAA Technical Center were issued a patent (#4,994,092) on an invention called the Helium Smoke Generator. The device generates simulated smoke at ambient temperatures having the buoyant properties of smoke produced by a fire. This allows realistic simulation of the buoyant properties of Par 6 5
1/6/94 AC 25-9A smoke for use in smoke penetration and evacuation tests. Information on this device may be obtained from:
Manager, Fire Satety Branch, ACD-240 FAA Technical Center Atlantic City International Airport, New Jersey 08405.
(7) Paper Towel Burn Box Smoke Generator. The "Burn Box" is intended for use in smoke detection system testing in Crew Rest and Lavatory areas.
Appendix II provides the data necessary to build and operate an FAA-approved Paper Towel Burn Box Generator.
(8) Continuous Smoke in the Cockpit. Although the FAR does not require the consideration of continuous smoke generation/evacuation, the FAA recommends that the airframe design address this situation. Accordingly, paragraphs 12a(1) and 12e(3) recommend addressing continuous smoke generation/evacuation in the cockpit.
SUBJECTS AND DEFINITIONS. For purposes of this AC, the following are applicable:
a. Smoke. The airborne solid and liquid particulates and gases evolved when a material undergoes pyrolysis or combustion, together with the quantity of air that is entrained or otherwise mixed into the mass.
b. Production and detection of smoke. Particulate smoke is a product of incomplete combustion. It is generated in both smoldering and flaming combustion, although the nature of particles and their mode of formation are very different. Smoke from smoldering is similar to that obtained when any carbon based material is heated to temperatures at which there is chemical degradation and evolution of volatiles. The volatiles mix with cool ambient air to give mist consisting of minute droplets of tar and liquids with high boiling points. Smoke from flaming combustion consists entirely of solid particles. While a small portion of these may be produced by ablation of a solid under conditions of high heat flux, most are formed in the gas phase as a result of incomplete combustion and high temperature pyrolysis reactions at ow temperature conditions. Smoke may be detected by several methods-- ionization, photoelectric light scattering, photoelectric light obscuration, and cloud chamber.
c. Buoyancy and Stratification. A fire generates heat. This heat causes gases in the vicinity of fire to increase in temperature and expand. This produces torces, termed buoyancy, which cause the not gases to rise and tlow away from the fire. Buoyancy forces are responsible for not gases being expelled through the upper portion of any ventilating openings or through any other suitable leakage path. Hot gases that rise up from a fire due to buoyancy mix with local air and cool down. This causes a reduction in the buoyancy and reduction in the upward mobility of the gases. The gases accumulate in layers or strata. This accumulation of gases in layers is termed as stratification. Buoyancy and stratification of smoke is dependent on a large number of variables--fuel, burn rate, environmental conditions, chamber geometry, leakage paths, etc. A combustible material smoke generator 6 Par 6
produces a higher buoyancy smoke than a theatrical smoke generator due to its higher temperature. The smoke from a combustible material smoke generator also spreads quickly and the stratification occurs from top down as the smoke cools in the upper layers. By contrast, the spread from the theatrical smoke generator (without helium modification) occurs slowly and the stratification progresses from floor up.
d. On-board smoke sources.
On board smoke or fire may occur due to several reasons. Probable causes are--failure of electrical equipment (shorted wires), overheating of equipment (loss of thermostats or controlling devices), leakage of hot air from pneumatic ducts or spillage of combustible fluid (hydraulic oil, glycol) on a hot surface. Incidents of on-board fire (excluding engine fires) are extremely rare but they do occur and can compromise safety. Smoke sources should be considered in all airplane compartments which contain combustible materials and potential ignition sources (baggage, cargo, passenger, equipment bay, crew rest area, galley, lavatory, etc.). Fires in inaccessible areas
(e.g., equipment bays, Class C cargo compartments) should be assumed to be continuous, i.e., capable of continuously generating products of combustion until it can be visually verified that the fire has been extinguished. This is required tor the development of tire suppression procedures and to show compliance with the control and containment (as well as continued safe flight and landing) requirements specified in §§ 25.831, 25.869, and 25.1309. The adequacy of the smoke control and containment means should be demonstrated during airplane flight tests, see § 25.855.
(2) Failures that cause fire and smoke should be included in the failure assessment conducted under 99 25.831, 25.869 (previously 25.1359), and s 25.1309. It should be determined, for each failure condition considered for this assessment, whether smoke detectors and specific fire or smoke procedures are warranted and whether the failure or secondary effects should be prevented through the use of isolation, containment, extinguishers, etc. The likelihood of a continuous exposure to smoke may be based on a failure evaluation which would include the sources of failure, contributing materials, failure preventative measures, and smoke control or containment means. The adequacy of the smoke control and the containment means should be verified by smoke
e. Smoke Toxicity. Sections of the FAR containing reference to this or related subjects are §§ 25.831, 25.851, and 25.857. Adverse operating conditions and their effects on the airplane and occupants are addressed in section § 25.1309.
The products of combustion depend on the fuel consumed, the environment (oxygen availability), the rate of combustion and numerous other factors.
fire suppression agent and its products of combustion and decomposition also contribute components. Because of these variables, the toxic levels of smoke and extinguishing agent have not been defined for certification testing.
understand how the methods of compliance for each test have been derived related to the variables of smoke and extinguishing agent, see the discussion under the applicable rules, Appendix I.
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f. Light Transmissibility Measuring Device (or Transmissiometer).
instrument is described in the reference material listed in paragraph 3e(2) and paragraphs 9c and Ile 7). Test personnel use this instrument during smoke penetration tests to judge smoke density by measuring a reduction in light transmission. This instrument should not be contused with smoke detectors (photosensitive or ionization type) which are permanently installed on the airplane to warn the flightcrew of the presence of smoke in cargo compartments, galleys, lavatories, equipment bays and equipment cooling systems.
g. Airplane Modifications. Airplane modifications that may require smoke tests include the alteration of, addition to or removal of, pneumatic systems (bleed air, air conditioning, pressurization, ducting and distribution, equipment cooling, etc.), baggage or cargo compartments, interiors, interior seals, cockpit panels, etc. Each modification should be evaluated to determine if smoke testing is required. The assessment should consider all modifications, including those behind and between panels and between panels and the fuselage skin.
8. AIRPLANE FLIGHT MANUAL (AFM) FIRE AND SMOKE PROCEDURES.
a. Section 25.1585(a) requires that information and instructions must be furnished together with recommended procedures for fire. This information must be included in the emergency procedures section of the AFM and should be included in the Operations Manual. The effectiveness of emergency procedures should be evaluated for probable fire scenarios.
b. Section 25.831 allows the use of depressurization within safe limits to evacuate smoke from the cockpit and passenger compartment. A number of manufacturers have developed and tested procedures to aid in smoke evacuation.
Those techniques have been found to be effective for the specific airplane models that utilize them. Typically, the AFM procedures call for increasing the cabin altitude to a sate level, such as 10,000 feet. In some cases, the procedures suggest descending to an intermediate altitude, such as 15,000 feet, and completely depressurizing the airplane. In either case, if this procedure is used, the following should be ensured:
(i) The oxygen masks do not automatically deploy,
(ii) Rapid decompression does not cause false fire warnings, and
(iii) Airplane and passenger safety is not compromised.
Some cargo airplanes have a smoke procedure that recommends that the crew turn off the ventilating air, don their oxygen equipment, and gradually raise the cabin altitude to 25,000 feet or more; the purpose being to limit the oxygen supply and thereby controlling a fire until the airplane can descend to procedures for fire and smoke should include instructions for the flightcrew as well as the Operations Manual (if applicable), emergency 8 Par 7
AC 25-9A 1/6/94 to immediately proceed to the nearest suitable airport for landing when fire is detected. Deviations from this procedure may be allowed if:
(i) It can be visually verified that the fire has been extinguished in compartments which allow access to all areas of the compartment (reliance on observations of absence of smoke or fire detector annunciation is not allowed), and
(ii) Damage assessment indicates it is safe to continue the flight.
d. In the event of an explosion in a cargo compartment equipped with a liner:
(i) Assume the liner is ruptured.
(ii) If equipped with a smoke detection system, assume it is unreliable due to possible damage or ventilation changes caused by loss of the liner integrity.
(iii) If equipped with a fire extinguishing system, the AFM procedure should recommend immediate discharge of the fire extinguishing agent as a precautionary measure.
(iv) The AFM should require or direct the flightcrew to land at the nearest suitable airport.
SMOKE TESTS. There are three smoke tests associated with the certification process; smoke detection tests, smoke penetration tests and smoke evacuation tests. Table 1 summarizes the smoke tests required and/or recommended for certification of several common types of airplane compartments. Also listed are the appropriate advisory circular paragraphs and regulatory references for each type of compartment.
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Table 1 - Smoke Tests Cargo Compartments Smoke Smoke Advisory Circular Compartment Classification Detection Penetration References Related FAR's Class A (a) NIA 9a, 9b. Sc. 10.& 11 § 25.855. § 25.857, Class B Yes Yes § 25.858. & § 25.1301 Class C Yes Yes Class D (a) Yes Class E Yes Yes Smoke Smoke Advisory Circular Crew Rest Areas Detection Penetration References Related FAR's Curtained area in passenger 6c(4), 9a, 9b, 9c, 9d, § 25.831 & § 25.1301 compartment or flight deck. NIA N/A 10, & 11 in passenger compartment or flight deck with:
(i) Curtained entrance (a) N/A
(li) Area enclosed by walls, floor to ceiling, and door (a) (b) Remote (not in passenger compartment or flight deck). (a) (b) Smoke Smoke Advisory Circular Lavatories Detection Penetration References Related FAR's Lavatores with: Sc(3), 9a, 9b, 9c, 9d. § 25.831, § 25.854, &
(i) Curtained entrance. Yes NIA 10. & 11 § 25.1301
(ii) Door. Yes (b) Smoke Smoke Advisory Circular Galleys Detection Penetration References Related FAR's in passenger compartment or 9a. 9b. 9c. 9d. 10. & 11 § 25.831 & § 25.1301 flight deck with:
(i) Curtained entrance (a) (b)
(il) Area enclosed by walls, floor to ceiling, and door (a) (b) Remote (not in passenger compartment or flight deck). (a) (b) Equipment Bays & Smoke Smoke Advisory Circular Equipment Cooling Systems Detection Penetration References Related FAR's For all equipment bays and 9a, 9b. 9c. 9d. 10. & 11 § 25.831 & § 25.1301 equipment cooling systems. (a) Yes Smoke Smoke Smoke Advisory Circular Cockpits Detection Penetration Evacuation References Related FAR'S For all cockpits N/A N/A Yes 9b & 12 § 25.831 & § 25.1301
(a) = Yes, if a smoke detection system is installed.
(b) = Test recommended.
NIA = Test not applicable.
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a. Acceptable Smoke Generators for Smoke Detection Tests.
(1) Generators. An appropriate generator should be selected, e.g.,:
Paper Towel Burn Box (see Appendix I1);
(¡i) Rosco Theatrical smoke generator [see 10a.3)];
(iii) Helium-injected Rosco Theatrical smoke generator;
(iv) A pipe or cigar;
(v) A Woodsman Bee Smoker; or (Vi) Any other acceptable smoke generator.
(2) Fuel. Representative materials should be selected, e.g.,:
(ї) Plastic;
(ii) Rags;
(iii) Tobacco;
(iv) Burlap;
(v) Paper; or
(vi) Any other acceptable fuel
b. Acceptable Smoke Generators for Smoke Penetration and Smoke Evacuation Tests.
(1) Smoke Generators. An appropriate smoke generator should be selected, e.g.,:
(i) Cloudmaker Model 11-48 (B, D);
(ii) Farnum Barn Fogger;
(iii) Pepper Fog;
Cloud Nine Superseded by Maxi-Mist);
Maxi-Mist;
(vi) Mini-Mist (Suitable for small compartments);
Rosco Smoke Machine (Model Pro 1500 or Pro 3000); or
(viii) Any other acceptable smoke generator
(2) Fuels. Use the fuel recommended by the smoke generator manufacturer, e.g.,:
(i) Silicon Oil;
(ii) Paraffin Oil;
(iii) Mineral Oil;
(iv) Propylene Glycol or water solutions of propylene glycol;
(v) Ethylene Glycol; or
(vi) Any other acceptable fuel
c. Smoke Penetration lest Equipment and Suppliers for the Alternate Technique (see lle(/)).
(1) Light Source. Helium Neon Laser Tube outputting light at a wavelength of 632.8 nanometers, manufactured by Cw Radiation Co., A Division of Aerotech, 101 Zeta Drive, Pittsburgh, PA 15238.
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(2) Photo (Light) Detector. Model UDT 161. Manufactured by United Detector Technology, 3939 Landmark Street, Culver City, CA 90232.
(3) Smoke Generator. Cloudmaker 11-48. Supplied by Testing Machines, Inc., 400 Bayview Ave., Amityville, NY 11701.
d. Airplane Test Conditions. Flight tests are required to demonstrate compartment accessibility, and exclusion of hazardous quantities of smoke or extinguishing agent from entering into compartments occupied by the crew or passengers. Because detector sensitivity and in-flight compartment airflows differ from those found in ground tests, smoke detection tests should also be conducted in flight. For certification tests, the airplane and relevant systems should be in the production configuration.
(1) The compartment accessibility test should be performed during cruise with normal ventilation airflow and normal cabin-to-ambient pressure differential.
(2) The penetration tests should be conducted during cruise and descent at normal cabin-to-ambient pressure differential with:
(ї) Normal ventilation flow rate, and
(ii) Under airplane dispatchable ventilation flow rate conditions.
(3) The smoke detection system effectiveness test should be conducted during cruise at normal cabin-to-ambient pressure differential with maximum normal ventilation flow rate. The airplane should be operated in the various dispatchable ventilation and pressurization configurations (one air conditioning pack, two air conditioning packs, unpressurized, etc.) for the cruise condition. The combustible material used for testing should be representative of what would be expected to burn in the area under consideration.
e. Flight Test Hazards. Smoke detection, penetration, and evacuation tests can be hazardous. Test should be conducted with the concurrence of Air Traffic Control. Reduced visibility in the cockpit during these tests may require conduct of tests away from air traffic. Protective breathing equipment and adequate communications must be provided for all crew members, with emphasis on cockpit crew monitoring of cabin crew's safety.
f. Test Limitations.
The tests described have been developed primarily for cargo, storage, or baggage compartments, equipment bays, equipment cooling systems, and other non-continuously occupied areas (e.g., galleys, lavatories and crew rest areas) that are accessible in flight. Modifications of the test procedures or equipment may be needed to validate a test procedure for locations that are not accessible in flight. The effect that the smoke generator has on the test should be considered for small compartments, i.e., galleys, lavatories and crew rest areas where smoke from a large generator may not be appropriate.
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