The following references provide information which can be helpful in understanding the requirements contained in various sections of the standard:

1. Bresnahan, Thomas F., and Bryk, Joseph, "The Hazard Association Values of Accident Prevention Signs", Journal of American Society of Safety Engineers; January 1975.

2. Dreyfuss, H., Symbol Sourcebook, McGraw Hill; New York, NY, 1972.

3. Glass, R.A. and others, Some Criteria for Colors and Signs in Workplaces, National Bureau of Standards, Washington DC, 1983.

4. Graphic Symbols for Public Areas and Occupational Environments, Treasury Board of Canada, Ottawa, Canada, July 1980.

5. Howett, G.L., Size of Letters Required for Visibility as a Function of Viewing Distance and Observer Acuity, National Bureau of Standards, Washington DC, July 1983.

6. Lerner, N.D. and Collins, B.L., The Assessment of Safety Symbol Understandability by Different Testing Methods, National Bureau of Standards, Washington DC, 1980.

7. Lerner, N.D. and Collins, B.L., Workplace Safety Symbols, National Bureau of Standards, Washington DC, 1980.

8. Modley, R. and Meyers, W. R., Handbook of Pictorial Symbols, Dover Publication, New York, NY, 1976.

9. Product Safety Signs and Labels, FMC Corporation, Santa Clara, CA, 1978.

10. Safety Color Coding for Marking Physical Hazards, Z53.1, American National Standards Institute, New York, NY, 1979.

11. Signs and Symbols for the Occupational Environment, Can. 3-Z-321-77, Canadian Standards Association, Ottawa, September 1977.

12. Symbols for Industrial Safety, National Bureau of Standards, Washington DC, April 1982.

13. Symbol Signs, U.S. Department of Transportation, Washington DC, November 1974.

[39 FR 23502, June 27, 1974, as amended at 43 FR 49749, Oct. 24, 1978; 43 FR 51759, Nov. 7, 1978; 49 FR 5322, Feb. 10, 1984; 51 FR 33260, Sept. 19, 1986; 61 FR 5507, Feb. 13, 1996; 61 FR 9227, March 7, 1996]