4. APTA SS-PS-004-99, Rev. 1 Standard for Low-Location Exit Path ...

4. APTA SS-PS-004-99, Rev. 1 Standard for Low-Location Exit Path ... 4. APTA SS-PS-004-99, Rev. 1 Standard for Low-Location Exit Path ...

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APTA SS-PS-004-99, Rev. 1 Edited 4-1-04 d) Begin the test by making the railcar interior completely dark. This may be done by placing the car in a dark area of the shop (car wash, etc.), working out-of-doors at night, or by masking all windows and doors with heavy paper. Close all doors. Make sure no other personnel will attempt to enter the car during the test procedure. e) Turn on normal interior lighting, make sure all fixtures are operating, and wait 20 minutes to ensure that all tubes have reached stable operating temperatures. f) Start stopwatch and go through car quickly peeling back opaque tape. Leave about three inches in place to mark the location of each covered area. g) Be sure that emergency lighting circuits are disabled. h) Exactly 60 minutes after tape was peeled back, shut off all lighting. i) Exactly 90 minutes later (stopwatch reads 2 hours, 30 minutes), begin taking luminance readings using a luminance meter as described in Annex B, at each location previously covered by the opaque tape immediately adjacent to portion of the tape remaining. This procedure requires a two-person team: one to place the detector and call out readings, the other to write them down on a data sheet. Both persons must be equipped with small, red-filtered flashlights to see what they are doing. (Red light does not charge photoluminescent materials.) The measurements should be made in the same order that the tape was peeled back so they are all made 2 hours and 30 minutes (+/-10 seconds), after the moment of peel back. With practice, a dozen measurements can be completed in less than three minutes. j) If the period that the LLEPM samples were covered by opaque tape was four days or longer and the HPPL materials are wider than the detector aperture of 1.38 inches (35 mm), no adjustments to the data are necessary. Take a simple arithmetic average of the samples. If the average exceeds 7.5 mcd/m 2 , the car has passed. If these conditions are not satisfied, perform the following corrections before taking the average. k) If the dimensions of the LLEPM samples to be measured are less than the luminance sensor aperture: 1.97 in. (50 mm) or 1.38 inches (35 mm), a special aperture plate should be ordered with a diameter slightly less than the width of the strips. The luminance meter manufacturer will supply a correction factor for this plate. Each reading must be multiplied by this correction factor. l) Alternatively, a correction factor can be determined for a standard aperture by calculating the ratio of its area to that of the area of HPPL material within the aperture. The equation for this trigonometric calculation is found in several standard handbooks, and Volpe staff will supply values on request for any given HPPL material width. For example, a HPPL sample of 1.3 inch (33 mm) width requires a correction factor of 1.016 for a 35 mm aperture. These correction factors assume that the detector is precisely centered on the material when the measurements are taken. Hence, it is better to order a special aperture plate so that it is easy to center the detector on the material. 4.21 Volume VI - Passenger System

APTA SS-PS-004-99, Rev. 1 Edited 4-1-04 m) The minimum darkness period to condition the HPPL material is 48 hours. If the period during which the samples are covered by opaque tape is less than four days, an additional correction is required. Subtract the values in the following table from the measured luminance value: n) Example: Covered period 48 to 72 hours 0.2 72 to 96 hours 0.1 Greater than 96 hours 0 4.22 Correction value (mcd/m 2) The purpose of this correction is to compensate for the small amount of residual charge that may remain in the HPPL material from before the time it was covered with opaque gaffer’s tape. o) Although luminance meter averages are used to indicate that the LLEPM meet minimum criteria of 7.5 mcd/m 2 , if individual HPPL segments are noticeably less bright, or any other indication is seen that the LLEPM does not meet the criteria described in Section 5 of this standard, gaps exist between segments that are greater than 18 inches and alternative corrective actions must be taken to increase light output. D.3 Alternatives to increase light output If during the rail car interior field tests, the performance of the HPPL material fails to meet the criteria of illuminance of 5 fc using normal lighting or luminance of 7.5 mcd/m 2 after normal power is removed for 1.5 hours as measured directly on the material surface, there are several alternative actions that can be taken to increase the HPPL light output levels: a) All of the light fixtures near the LLEPM test samples should be checked to ensure proper working order. b) Light fixtures must be clean and the diffusers not yellowed with age. Old, dirty fixtures have been measured with less than half the light output of clean ones with new diffusers. c) Fluorescent tubes should be checked to ensure they are not near the ends of their service lives, where light output drops significantly. d) Incandescent lamps or warm white tubes should be replaced with cool, white fluorescent tubes. e) Existing fluorescent tubes should be replaced with those of recent design that provide Volume VI - Passenger System

<strong>APTA</strong> <strong>SS</strong>-<strong>PS</strong>-<strong>004</strong>-<strong>99</strong>, <strong>Rev</strong>. 1<br />

Edited 4-1-04<br />

m) The minimum darkness period to condition the HPPL material is 48 hours. If the<br />

period during which the samples are covered by opaque tape is less than four days, an<br />

additional correction is required. Subtract the values in the following table from the<br />

measured luminance value:<br />

n) Example:<br />

Covered period<br />

48 to 72 hours 0.2<br />

72 to 96 hours 0.1<br />

Greater than 96 hours 0<br />

<strong>4.</strong>22<br />

Correction value<br />

(mcd/m 2)<br />

The purpose of this correction is to compensate <strong>for</strong> the small amount of residual<br />

charge that may remain in the HPPL material from be<strong>for</strong>e the time it was covered<br />

with opaque gaffer’s tape.<br />

o) Although luminance meter averages are used to indicate that the LLEPM meet<br />

minimum criteria of 7.5 mcd/m 2 , if individual HPPL segments are noticeably less<br />

bright, or any other indication is seen that the LLEPM does not meet the criteria<br />

described in Section 5 of this standard, gaps exist between segments that are greater<br />

than 18 inches and alternative corrective actions must be taken to increase light<br />

output.<br />

D.3 Alternatives to increase light output<br />

If during the rail car interior field tests, the per<strong>for</strong>mance of the HPPL material fails to<br />

meet the criteria of illuminance of 5 fc using normal lighting or luminance of 7.5 mcd/m 2<br />

after normal power is removed <strong>for</strong> 1.5 hours as measured directly on the material surface,<br />

there are several alternative actions that can be taken to increase the HPPL light output<br />

levels:<br />

a) All of the light fixtures near the LLEPM test samples should be checked to ensure<br />

proper working order.<br />

b) Light fixtures must be clean and the diffusers not yellowed with age. Old, dirty<br />

fixtures have been measured with less than half the light output of clean ones with<br />

new diffusers.<br />

c) Fluorescent tubes should be checked to ensure they are not near the ends of their<br />

service lives, where light output drops significantly.<br />

d) Incandescent lamps or warm white tubes should be replaced with cool, white<br />

fluorescent tubes.<br />

e) Existing fluorescent tubes should be replaced with those of recent design that provide<br />

Volume VI - Passenger System

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