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This section defines the lighting configuration, design
criteria, and performance characteristics/requirements
for both interior and exterior vehicle.
Interior lighting includes the main
overhead fixtures, emergency lighting, control and
power input requirements for both the main cabin and
operators cab. Exterior lighting includes main
illumination fixtures (headlamps, RR lamp, etc.),
marker and warning lighting, and control and power
input requirements.
The lighting levels or “illuminance” are typically
specified in Lux (SI) or Foot Candles (US) at the position of
interest. (Example: 20fc at floor level). (1 footcandle = 10.7639
lux)
Typical values for illuminance (or luminous emittance) are shown
below for reference:
| Light Level |
Typical Lux |
Typical Foot Candel |
| Moonlight (Full Moon) |
0.25~1.0 lux |
0.02~0.09 fc |
| Shady room in daylight |
100 lux |
9.3 fc |
| Typical office |
300 to 800 lux |
27.9 to 74.3 fc |
| TV Studio Lighting |
1,000 lux |
93 fc |
| Overcast summer day |
30,000 to 40,000 lux |
2,787 to 3,716 fc |
| Very bright summer day |
up to 100,000 lux |
9,290 fc |
The Illuminating Engineering Society of North America (IESNA)
recommends illuminance levels of 30-75 foot-candles (323 to 807
lux) for office / paper tasks, but much lower levels, 5-10 foot-candles
(54 to 108 lux), for computer work.
Rail vehicle lighting levels commonly used are generally; 11
to 50 lux (1 to 5 fc) for low level (or emergency) lighting, 150
to 200 lux (14 to 29 fc) for general lighting, and 300 to 350
lux (29 to 32 fc) for task lighting, or reading level applications.
Adjustable lighting should be used for task lighting where computer
monitors or LCD/CRT displays are used.
Exterior lighting includes includes marker lights,
indicator lamps, warning lights, and fault annunciations, as well
as main lighting (headlights/railroad lights) to illuminate the
track and wayside.
Additional lighting requirements for Low Location Exit Path Marking
(LLEPM) are now in effect. This lighting is intended to mark the
pathway to the exits in the event of a total lighting failure
using either active or passive lighting methods. Passive illumination
such as a High Performance Photo-Luminescent material (HPPL) are
commonly used in addition to active lighting. Please refer to
APTA SS-PS-004-99 - Standard for Low-Location Exit Path Marking.
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