Nebraska Administrative Code › Topic - EDUCATION, DEPARTMENT OF › Title 92 - NEBRASKA DEPARTMENT OF EDUCATION › Chapter 92 - REGULATIONS GOVERNING THE MINIMUM EQUIPMENT STANDARDS AND SAFETY INSPECTION CRITERIA FOR PUPIL TRANSPORTATION VEHICLES › Appendix D - SCHOOL BUS SEAT UPHOLSTERY FIRE BLOCK TEST

Current through June 17, 2024
A. TEST CHAMBER
Cross Section
The suggested test chamber is same cross section as bus body
				  in which seats are used with rear section on each end. If bus section is not
				  used, cross section to be 91" ± 1" in width x 75" ± 3" in height.
				  There shall be a door, which does not provide ventilation, in the center of
				  each end of the test chamber. The doors shall be 38" ± 3" in width and
				  53" ± 3" in height and include a latch to keep the doors closed during
				  the test. See Figure 1.
Length
Length of chamber shall allow 3 rows of seats at the minimum
				  spacing recommended by the installer or required by Federal Motor Vehicle
				  Safety Standards. See Figure 1, Detail A.
In order that different types of seats may be tested in the
				  same chamber, a length tolerance of plus 45" is allowed.
Ventilation
One ventilation opening shall be in each end of the test
				  chamber and shall be 325 square inches ± 25 square inches. The bottom of
				  the opening shall be 30" ± 3" above the chamber floor. Ventilation
				  openings shall be on the same side of the test chamber. See Figure 1.
There shall be no ventilation openings along the length of
				  the test chamber.
A forced air ventilation system may not be used.
Baffles shall be used to prevent wind from blowing directly
				  into the ventilation openings.
Camera View Area
An opening covered with glass shall be provided at the
				  midpoint of the chamber length for camera viewing. The opening shall allow the
				  camera to view the seat parallel to the seat width. See Figure 1.
Click here to
				  view
B. TEST SAMPLE
Sample shall be fully-assembled seat.
Record the weight of all padding upholstery prior to
				  assembly. Record the weight of the fully assembled seat.
IGNITION
A paper grocery bag whose dimensions are approximately 7" x
				  11" x 18" is used to contain double sheets of newsprint (black print only,
				  approximately 22" x 28"). The total combined weight of bag and newspaper shall
				  be 7 oz. + .5 oz.
TEST PROCEDURE
1. Install three (3) seats in test chamber at minimum spacing
				  per installer recommendation of FMVSS requirement. Seats shall be perpendicular
				  to the dimension indicated as "length" in Figure 1 Detail A. Install so that
				  seat frames will not fall during test. Seat width shall be determined so that
				  maximum passenger capacity per row (2 seats) for the seat style shall be
				  tested.
2. For each test, position ignition source in the following
				  positions outlined. Widest seat in the center row shall be tested.
Position A
Position ignition source with 18" dimension in contact with
				  seat cushion and touching seat back. Center bag on top of cushion. See Figure
				  2.
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				  view
Position B
Position ignition source on floor behind seat with 18"
				  dimension on floor and parallel to seat width centered on width so that rear of
				  bag does not extend rear of seat back. See Figure 3.
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				  view
Position C
Position ignition source on floor on aisle side of seat with
				  18" dimension on floor and perpendicular to seat width touching seat leg with
				  centerline of bag at center of seat back. See Figure 4
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				  view
3. A wooden match shall be used to light the ignition source.
				  Time the test beginning where the ignition source is on fire until all flame is
				  out.
4. After each ignition source position test, weigh seat
				  assembly including loose materials on the seat. Do not include loose material
				  which has fallen off the seat onto the floor.
C. PERFORMANCE CRITERIA
For each ignition source position test, the seat tested must
				  meet all of the following criteria. A new seat specimen may be used for each
				  ignition source position test.
1. Maximum time from ignition to flameout shall be 8
				  minutes.
2. Flame shall not spread to any other seat with ignition
				  source in Position A and Position C.
3. Weight loss may not exceed 10% of pretest weight of
				  padding and upholstery.