Please help me with this one.  My understanding is that OSHA regs do not specifically address hard hat expiration dates, but generally default to ANSI standards, which state we must "follow manufacturers' instructions" regarding expiration dates and the need to replace a hard hat - even one in otherwise apparently good shape - when the expiration date is reached.  Is this accurate?  Is the date mark on the underside of a hard hat brim manufacture date or expiration date?  Is there a standard expiration time (e.g. 5 years) or does it vary by manufacturer?

Thanks

The date on the underside of hardhat was the date of manufacture,  As far as hardhat life, that is set by the manufacturer and I do believe most are 5 years for regular HH and 3 years for composites.

thanks Safety Joe