This is actually on the books for OSHA.
AGREEMENT: We agree that if you are a type of individual whose head meets the Standards of Protection under ANSI Z89.1-1969, you will not be required to wear a hard hat. Any employee who feels they may quilify should contact your foreman or your safety officer to arrange for testing.
PROCEDURES: Following the satisfactory completion of the test as described below, the employee will receive a certificate, which will identify your head as conforming to the requirements of American National Standards Institute (ANSI Z89.1-1969, cLASSES A, B, C, and D). A wallet size card will also be issued which must be carried with you at all times, while on the job site as proof that your head is in compliance.
* The test object (your head) wil receivea 24 hour water immersion test. The maximum permitted absorption is 0.5 percent by wheight.
* The impact test requires that you be placed in a horizontal position with your head upon a steel plate. An eight pound steel ball will be dropped upon your head from a height of 15 feet. (your head) must suffer no damage.
* The test object (your head) will be subject to a variety of acids, solvents and oils. After thorough testing with chemicals, it must exhibit no damage or deficiencies.
* A propane torch will be used to determine if your head is fire resistant. If it proves to be only "slow burning" you will receive a class A or B rating; however if holes should appear in your head, only a C or D rating will be issued.
* The final test will be to determine if your head is capable of withstanding an electrical charge. The head must sustane 2,000 volts AC, 60 Hz for a total of three minutes. The leakage current shall not exceed nine milliamperes.
* All of the above tests must be conducted at a variety of temperatures ranging from a minus twenty (-20) to one hundred forty (+140) degrees fahrenheit.