Construction workers need to wear hard hats when working under certain conditions. The Occupational Health and Safety Administration (OHSA) requires hard hats in certain situations but does not have specific requirements for replacement. The manufacturers make recommendations, but there is no federal or state mandate that requires employers to replace hard hats at any particular interval.
Aging of Hard Hats
A hard hat does not show wear, since it is made of a durable plastic. However, the climate, use, exposure to sunshine, chemicals and accidents degrade the hard hats over time. Hot, dry climates are particularly damaging to hard hats. OSHA recommends replacing a hard hat every two years. Some manufacturers suggest that hard hats be replaced every year.
Hard hats come with manufacturing date codes stamped into them, according to the requirements of OSHA rule ANSI Z89.1-2003. Workers can use the date codes to determine when it is time to replace the hard hat. If the hard hats are stored away from heat and chemicals, workers or the management can mark the date the hat was placed into service to keep track of the hard hat's useful life.
Any hard hat that has been struck by an object should be replaced. It is hard to see fine cracks in a hard hat, and the next time the hard hat suffers an impact it could break and not protect the head, causing skull damage. Any hard hat that has been dropped from a two-story building should be replaced. Used hard hats turned in from employees should be destroyed or recycled, if possible.
Suspension and Shell
Hard hats have suspension systems inside them that protect the head from blows, along with the shell. If any frayed straps or cracked connectors are apparent, the hard hat needs to be replaced. Hair oils and sweat also create wear and tear on the suspension system and contribute to hardening of the pliable plastics used inside. The suspension systems can be replaced with new ones if there is any doubt about their condition.