295
Federal Aviation Administration, DOT
§ 25.812
must be at least 45 percent. ‘‘Reflec-
tance’’ is the ratio of the luminous flux
reflected by a body to the luminous
flux it receives. When the reflectance
of the darker color is greater than 15
percent, at least a 30-percent difference
between its reflectance and the reflec-
tance of the lighter color must be pro-
vided.
(3) In the case of exists other than
those in the side of the fuselage, such
as ventral or tailcone exists, the exter-
nal means of opening, including in-
structions if applicable, must be con-
spicuously marked in red, or bright
chrome yellow if the background color
is such that red is inconspicuous. When
the opening means is located on only
one side of the fuselage, a conspicuous
marking to that effect must be pro-
vided on the other side.
(g) Each sign required by paragraph
(d) of this section may use the word
‘‘exit’’ in its legend in place of the
term ‘‘emergency exit’’.
[Amdt. 25–15, 32 FR 13264, Sept. 20, 1967, as
amended by Amdt. 25–32, 37 FR 3970, Feb. 24,
1972; Amdt. 25–46, 43 FR 50597, Oct. 30, 1978; 43
FR 52495, Nov. 13, 1978; Amdt. 25–79, 58 FR
45229, Aug. 26, 1993; Amdt. 25–88, 61 FR 57958,
Nov. 8, 1996]
§ 25.812
Emergency lighting.
(a) An emergency lighting system,
independent of the main lighting sys-
tem, must be installed. However, the
sources of general cabin illumination
may be common to both the emergency
and the main lighting systems if the
power supply to the emergency light-
ing system is independent of the power
supply to the main lighting system.
The emergency lighting system must
include:
(1) Illuminated emergency exit mark-
ing and locating signs, sources of gen-
eral cabin illumination, interior light-
ing in emergency exit areas, and floor
proximity escape path marking.
(2) Exterior emergency lighting.
(b) Emergency exit signs—
(1) For airplanes that have a pas-
senger seating configuration, excluding
pilot seats, of 10 seats or more must
meet the following requirements:
(i) Each passenger emergency exit lo-
cator sign required by § 25.811(d)(1) and
each passenger emergency exit mark-
ing sign required by § 25.811(d)(2) must
have red letters at least 1
1
⁄
2
inches high
on an illuminated white background,
and must have an area of at least 21
square inches excluding the letters.
The lighted background-to-letter con-
trast must be at least 10:1. The letter
height to stroke-width ratio may not
be more than 7:1 nor less than 6:1.
These signs must be internally elec-
trically illuminated with a background
brightness of at least 25 foot-lamberts
and a high-to-low background contrast
no greater than 3:1.
(ii) Each passenger emergency exit
sign required by § 25.811(d)(3) must have
red letters at least 1
1
⁄
2
inches high on a
white background having an area of at
least 21 square inches excluding the
letters. These signs must be internally
electrically illuminated or self-illumi-
nated by other than electrical means
and must have an initial brightness of
at least 400 microlamberts. The colors
may be reversed in the case of a sign
that is self-illuminated by other than
electrical means.
(2) For airplanes that have a pas-
senger seating configuration, excluding
pilot seats, of nine seats or less, that
are required by § 25.811(d)(1), (2), and (3)
must have red letters at least 1 inch
high on a white background at least 2
inches high. These signs may be inter-
nally electrically illuminated, or self-
illuminated by other than electrical
means, with an initial brightness of at
least 160 microlamberts. The colors
may be reversed in the case of a sign
that is self-illuminated by other than
electrical means.
(c) General illumination in the pas-
senger cabin must be provided so that
when measured along the centerline of
main passenger aisle(s), and cross
aisle(s) between main aisles, at seat
arm-rest height and at 40-inch inter-
vals, the average illumination is not
less than 0.05 foot-candle and the illu-
mination at each 40-inch interval is not
less than 0.01 foot-candle. A main pas-
senger aisle(s) is considered to extend
along the fuselage from the most for-
ward passenger emergency exit or
cabin occupant seat, whichever is far-
ther forward, to the most rearward pas-
senger emergency exit or cabin occu-
pant seat, whichever is farther aft.
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14 CFR Ch. I (1–1–24 Edition)
§ 25.812
(d) The floor of the passageway lead-
ing to each floor-level passenger emer-
gency exit, between the main aisles
and the exit openings, must be pro-
vided with illumination that is not less
than 0.02 foot-candle measured along a
line that is within 6 inches of and par-
allel to the floor and is centered on the
passenger evacuation path.
(e) Floor proximity emergency es-
cape path marking must provide emer-
gency evacuation guidance for pas-
sengers when all sources of illumina-
tion more than 4 feet above the cabin
aisle floor are totally obscured. In the
dark of the night, the floor proximity
emergency escape path marking must
enable each passenger to—
(1) After leaving the passenger seat,
visually identify the emergency escape
path along the cabin aisle floor to the
first exits or pair of exits forward and
aft of the seat; and
(2) Readily identify each exit from
the emergency escape path by ref-
erence only to markings and visual fea-
tures not more than 4 feet above the
cabin floor.
(f) Except for subsystems provided in
accordance with paragraph (h) of this
section that serve no more than one as-
sist means, are independent of the air-
plane’s main emergency lighting sys-
tem, and are automatically activated
when the assist means is erected, the
emergency lighting system must be de-
signed as follows.
(1) The lights must be operable
manually from the flight crew station
and from a point in the passenger com-
partment that is readily accessible to a
normal flight attendant seat.
(2) There must be a flight crew warn-
ing light which illuminates when power
is on in the airplane and the emergency
lighting control device is not armed.
(3) The cockpit control device must
have an ‘‘on,’’ ‘‘off,’’ and ‘‘armed’’ posi-
tion so that when armed in the cockpit
or turned on at either the cockpit or
flight attendant station the lights will
either light or remain lighted upon
interruption (except an interruption
caused by a transverse vertical separa-
tion of the fuselage during crash land-
ing) of the airplane’s normal electric
power. There must be a means to safe-
guard against inadvertent operation of
the control device from the ‘‘armed’’ or
‘‘on’’ positions.
(g) Exterior emergency lighting must
be provided as follows:
(1) At each overwing emergency exit
the illumination must be—
(i) Not less than 0.03 foot-candle
(measured normal to the direction of
the incident light) on a 2-square-foot
area where an evacuee is likely to
make his first step outside the cabin;
(ii) Not less than 0.05 foot-candle
(measured normal to the direction of
the incident light) for a minimum
width of 42 inches for a Type A
overwing emergency exit and two feet
for all other overwing emergency exits
along the 30 percent of the slip-resist-
ant portion of the escape route re-
quired in § 25.810(c) that is farthest
from the exit; and
(iii) Not less than 0.03 foot-candle on
the ground surface with the landing
gear extended (measured normal to the
direction of the incident light) where
an evacuee using the established escape
route would normally make first con-
tact with the ground.
(2) At each non-overwing emergency
exit not required by § 25.810(a) to have
descent assist means the illumination
must be not less than 0.03 foot-candle
(measured normal to the direction of
the incident light) on the ground sur-
face with the landing gear extended
where an evacuee is likely to make
first contact with the ground outside
the cabin.
(h) The means required in
§§ 25.810(a)(1) and (d) to assist the occu-
pants in descending to the ground must
be illuminated so that the erected as-
sist means is visible from the airplane.
(1) If the assist means is illuminated
by exterior emergency lighting, it
must provide illumination of not less
than 0.03 foot-candle (measured normal
to the direction of the incident light)
at the ground end of the erected assist
means where an evacuee using the es-
tablished escape route would normally
make first contact with the ground,
with the airplane in each of the atti-
tudes corresponding to the collapse of
one or more legs of the landing gear.
(2) If the emergency lighting sub-
system illuminating the assist means
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§ 25.813
serves no other assist means, is inde-
pendent of the airplane’s main emer-
gency lighting system, and is auto-
matically activated when the assist
means is erected, the lighting provi-
sions—
(i) May not be adversely affected by
stowage; and
(ii) Must provide illumination of not
less than 0.03 foot-candle (measured
normal to the direction of incident
light) at the ground and of the erected
assist means where an evacuee would
normally make first contact with the
ground, with the airplane in each of
the attitudes corresponding to the col-
lapse of one or more legs of the landing
gear.
(i) The energy supply to each emer-
gency lighting unit must provide the
required level of illumination for at
least 10 minutes at the critical ambient
conditions after emergency landing.
(j) If storage batteries are used as the
energy supply for the emergency light-
ing system, they may be recharged
from the airplane’s main electric power
system:
Provided, That, the charging
circuit is designed to preclude inad-
vertent battery discharge into charg-
ing circuit faults.
(k) Components of the emergency
lighting system, including batteries,
wiring relays, lamps, and switches
must be capable of normal operation
after having been subjected to the iner-
tia forces listed in § 25.561(b).
(l) The emergency lighting system
must be designed so that after any sin-
gle transverse vertical separation of
the fuselage during crash landing—
(1) Not more than 25 percent of all
electrically illuminated emergency
lights required by this section are ren-
dered inoperative, in addition to the
lights that are directly damaged by the
separation;
(2) Each electrically illuminated exit
sign required under § 25.811(d)(2) re-
mains operative exclusive of those that
are directly damaged by the separa-
tion; and
(3) At least one required exterior
emergency light for each side of the
airplane remains operative exclusive of
those that are directly damaged by the
separation.
[Amdt. 25–15, 32 FR 13265, Sept. 20, 1967, as
amended by Amdt. 25–28, 36 FR 16899, Aug. 26,
1971; Amdt. 25–32, 37 FR 3971, Feb. 24, 1972;
Amdt. 25–46, 43 FR 50597, Oct. 30, 1978; Amdt.
25–58, 49 FR 43186, Oct. 26, 1984; Amdt. 25–88,
61 FR 57958, Nov. 8, 1996; Amdt. 25–116, 69 FR
62788, Oct. 27, 2004; Amdt. 25–128, 74 FR 25645,
May 29, 2009]
§ 25.813
Emergency exit access.
Each required emergency exit must
be accessible to the passengers and lo-
cated where it will afford an effective
means of evacuation. Emergency exit
distribution must be as uniform as
practical, taking passenger distribu-
tion into account; however, the size
and location of exits on both sides of
the cabin need not be symmetrical. If
only one floor level exit per side is pre-
scribed, and the airplane does not have
a tailcone or ventral emergency exit,
the floor level exit must be in the rear-
ward part of the passenger compart-
ment, unless another location affords a
more effective means of passenger
evacuation. Where more than one floor
level exit per side is prescribed, at
least one floor level exit per side must
be located near each end of the cabin,
except that this provision does not
apply to combination cargo/passenger
configurations. In addition—
(a) There must be a passageway lead-
ing from the nearest main aisle to each
Type A, Type B, Type C, Type I, or
Type II emergency exit and between in-
dividual passenger areas. Each passage-
way leading to a Type A or Type B exit
must be unobstructed and at least 36
inches wide. Passageways between indi-
vidual passenger areas and those lead-
ing to Type I, Type II, or Type C emer-
gency exits must be unobstructed and
at least 20 inches wide. Unless there
are two or more main aisles, each Type
A or B exit must be located so that
there is passenger flow along the main
aisle to that exit from both the forward
and aft directions. If two or more main
aisles are provided, there must be un-
obstructed cross-aisles at least 20
inches wide between main aisles. There
must be—
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