Appendix B. NATIONAL SCHOOL BUS YELLOW

The color known as National School Bus Yellow was designated as such by the 1939 National Conference on School Bus Standards. The National Bureau of Standards of the United States Department of Commerce assisted in developing this color and its colorimetric specifications, as follows:

C.I.E. Chromaticity Coordinates		Daylight Reflectance Y (%)			Dominant Wavelength (in millicrons)			Excitation Purity P (%)
x	y	max.	std.	min.	max.	std.	min.	max.	std.	min.
.5211	.4549	—	41.	40.	584.5	583.5	582.5	—	93.7	89.0

At the 1980 Conference the colors in use were reviewed. A color standard was selected, slightly different from the above, and specific tolerances were chosen. These tolerances will insure a continuity of appearance from school bus to school bus, and within the same school bus when different elements are finished or refinished at different times. Specification for the Standard Color, with light and dark tolerances (Upper and Low Reflectances) are shown below in tabular form.

SPECIFICATION FOR STANDARD COLOR

For Source C
CIE Chromaticity Coordinates		Reflectance Y (%)	Reflectance tolerances
x	y		Upper	Lower
.5089	.4408	40.14%	41.77%	38.45%

Source

The provisions of this Appendix B adopted August 19, 1983, effective August 20, 1983, 13 Pa.B. 2561; readopted December 4, 1987, effective December 5, 1987, 17 Pa.B. 5052. Immediately preceding text appears at serial page (83769).

Cross References

This appendix cited in 67 Pa. Code § 171.18 (relating to color); 67 Pa. Code § 171.47 (relating to color); 67 Pa. Code § 171.55 (relating to identification); 67 Pa. Code § 171.124 (relating to identification); and 67 Pa. Code § 171.134 (relating to identification).