107 

Federal Aviation Administration, DOT 

§ 121.221 

(c) Each certificate holder must com-

ply with the requirements of §§ 121.285 
through 121.291. 

(d) If the Administrator determines 

that, for a particular model of airplane 
used in cargo service, literal compli-
ance with any requirement under para-
graph (b) of this section would be ex-
tremely difficult and that compliance 
would not contribute materially to the 
objective sought, he may require com-
pliance only with those requirements 
that are necessary to accomplish the 
basic objectives of this part. 

(e) No person may operate under this 

part a nontransport category airplane 
type certificated after December 31, 
1964, unless the airplane meets the spe-
cial airworthiness requirements in 
§ 121.293. 

[Doc. No. 28154, 60 FR 65928, Dec. 20, 1995] 

§ 121.213 [Reserved] 

§ 121.215 Cabin interiors. 

(a) Except as provided in § 121.312, 

each compartment used by the crew or 
passengers must meet the require-
ments of this section. 

(b) Materials must be at least flash 

resistant. 

(c) The wall and ceiling linings and 

the covering of upholstering, floors, 
and furnishings must be flame resist-
ant. 

(d) Each compartment where smok-

ing is to be allowed must be equipped 
with self-contained ash trays that are 
completely removable and other com-
partments must be placarded against 
smoking. 

(e) Each receptacle for used towels, 

papers, and wastes must be of fire-re-
sistant material and must have a cover 
or other means of containing possible 
fires started in the receptacles. 

[Doc. No. 6258, 29 FR 19202, Dec. 31, 1964, as 
amended by Amdt. 121–84, 37 FR 3974, Feb. 24, 
1972] 

§ 121.217 Internal doors. 

In any case where internal doors are 

equipped with louvres or other ven-
tilating means, there must be a means 
convenient to the crew for closing the 
flow of air through the door when nec-
essary. 

§ 121.219 Ventilation. 

Each passenger or crew compartment 

must be suitably ventilated. Carbon 
monoxide concentration may not be 
more than one part in 20,000 parts of 
air, and fuel fumes may not be present. 
In any case where partitions between 
compartments have louvres or other 
means allowing air to flow between 
compartments, there must be a means 
convenient to the crew for closing the 
flow of air through the partitions, 
when necessary. 

§ 121.221 Fire precautions. 

(a) Each compartment must be de-

signed so that, when used for storing 
cargo or baggage, it meets the fol-
lowing requirements: 

(1) No compartment may include con-

trols, wiring, lines, equipment, or ac-
cessories that would upon damage or 
failure, affect the safe operation of the 
airplane unless the item is adequately 
shielded, isolated, or otherwise pro-
tected so that it cannot be damaged by 
movement of cargo in the compart-
ment and so that damage to or failure 
of the item would not create a fire haz-
ard in the compartment. 

(2) Cargo or baggage may not inter-

fere with the functioning of the fire- 
protective features of the compart-
ment. 

(3) Materials used in the construction 

of the compartments, including tie- 
down equipment, must be at least 
flame resistant. 

(4) Each compartment must include 

provisions for safeguarding against 
fires according to the classifications 
set forth in paragraphs (b) through (f) 
of this section. 

(b) 

Class A. 

Cargo and baggage com-

partments are classified in the ‘‘A’’ 
category if— 

(1) A fire therein would be readily 

discernible to a member of the crew 
while at his station; and 

(2) All parts of the compartment are 

easily accessible in flight. 

There must be a hand fire extinguisher 
available for each Class A compart-
ment. 

(c) 

Class B. 

Cargo and baggage com-

partments are classified in the ‘‘B’’ 
category if enough access is provided 
while in flight to enable a member of 

108 

14 CFR Ch. I (1–1–24 Edition) 

§ 121.223 

the crew to effectively reach all of the 
compartment and its contents with a 
hand fire extinguisher and the com-
partment is so designed that, when the 
access provisions are being used, no 
hazardous amount of smoke, flames, or 
extinguishing agent enters any com-
partment occupied by the crew or pas-
sengers. Each Class B compartment 
must comply with the following: 

(1) It must have a separate approved 

smoke or fire detector system to give 
warning at the pilot or flight engineer 
station. 

(2) There must be a hand fire extin-

guisher available for the compartment. 

(3) It must be lined with fire-resist-

ant material, except that additional 
service lining of flame-resistant mate-
rial may be used. 

(d) 

Class C. 

Cargo and baggage com-

partments are classified in the ‘‘C’’ cat-
egory if they do not conform with the 
requirements for the ‘‘A’’, ‘‘B’’, ‘‘D’’, or 
‘‘E’’ categories. Each Class C compart-
ment must comply with the following: 

(1) It must have a separate approved 

smoke or fire detector system to give 
warning at the pilot or flight engineer 
station. 

(2) It must have an approved built-in 

fire-extinguishing system controlled 
from the pilot or flight engineer sta-
tion. 

(3) It must be designed to exclude 

hazardous quantities of smoke, flames, 
or extinguishing agents from entering 
into any compartment occupied by the 
crew or passengers. 

(4) It must have ventilation and draft 

controlled so that the extinguishing 
agent provided can control any fire 
that may start in the compartment. 

(5) It must be lined with fire-resist-

ant material, except that additional 
service lining of flame-resistant mate-
rial may be used. 

(e) 

Class D. 

Cargo and baggage com-

partments are classified in the ‘‘D’’ 
category if they are so designed and 
constructed that a fire occurring there-
in will be completely confined without 
endangering the safety of the airplane 
or the occupants. Each Class D com-
partment must comply with the fol-
lowing: 

(1) It must have a means to exclude 

hazardous quantities of smoke, flames, 
or noxious gases from entering any 

compartment occupied by the crew or 
passengers. 

(2) Ventilation and drafts must be 

controlled within each compartment so 
that any fire likely to occur in the 
compartment will not progress beyond 
safe limits. 

(3) It must be completely lined with 

fire-resistant material. 

(4) Consideration must be given to 

the effect of heat within the compart-
ment on adjacent critical parts of the 
airplane. 

(f) 

Class E. 

On airplanes used for the 

carriage of cargo only, the cabin area 
may be classified as a Class ‘‘E’’ com-
partment. Each Class E compartment 
must comply with the following: 

(1) It must be completely lined with 

fire-resistant material. 

(2) It must have a separate system of 

an approved type smoke or fire detec-
tor to give warning at the pilot or 
flight engineer station. 

(3) It must have a means to shut off 

the ventilating air flow to or within 
the compartment and the controls for 
that means must be accessible to the 
flight crew in the crew compartment. 

(4) It must have a means to exclude 

hazardous quantities of smoke, flames, 
or noxious gases from entering the 
flight crew compartment. 

(5) Required crew emergency exits 

must be accessible under all cargo 
loading conditions. 

§ 121.223 Proof of compliance with 

§ 121.221. 

Compliance with those provisions of 

§ 121.221 that refer to compartment ac-
cessibility, the entry of hazardous 
quantities of smoke or extinguishing 
agent into compartments occupied by 
the crew or passengers, and the dissipa-
tion of the extinguishing agent in Class 
‘‘C’’ compartments must be shown by 
tests in flight. During these tests it 
must be shown that no inadvertent op-
eration of smoke or fire detectors in 
other compartments within the air-
plane would occur as a result of fire 
contained in any one compartment, ei-
ther during the time it is being extin-
guished, or thereafter, unless the extin-
guishing system floods those compart-
ments simultaneously.