Do hard hats expire? Not on a legal date: neither OSHA nor ANSI sets an expiration date, but every manufacturer sets a service life, usually counted from the date of manufacture stamped inside the shell. Many makers recommend replacing the suspension about every 12 months and the shell within a few years, and any damaged hat must be replaced right away.
Why hard hats “expire”
Hard hat shells are plastic, and plastic degrades. Sunlight, heat, cold, chemicals and everyday knocks slowly reduce its ability to absorb impact. The suspension straps also stretch and wear. A hat that looks fine can still be weaker than when it was new, which is why manufacturers set a service life.
How to read a hard hat date stamp
Look inside the shell, usually under the brim at the back or inside the crown. Most makers use a small round dial molded into the plastic:
- The center number is the year, often the last two digits (for example 24 for 2024).
- The arrow points to the month around the outside of the dial, numbered 1 to 12.
Some hats use a printed date or a code instead. If you can’t work it out, the manufacturer’s instructions explain their format. The suspension usually carries its own separate date.
Typical service life
| Part | Common manufacturer guidance |
|---|---|
| Suspension | About 12 months from first use |
| Shell | Often 2–5 years, depending on maker and material |
| After impact or damage | Replace immediately |
Some makers count from the date of manufacture, others from the date the hat is put into service. Write the in-service date inside the shell with a marker if your employer allows it.
Signs your hard hat has expired early
- Chalky, faded or dull surface
- Cracks, crazing (fine surface cracks) or dents
- Brim that creaks or cracks when flexed
- Stretched, frayed or stiff suspension straps
- Label worn off
Buying tip
Check the date stamp when a new hat arrives. A hat that sat in a warehouse for a long time has already used part of its shelf and service life, depending on how the maker counts it. If the date is old, ask the seller or the manufacturer.
For western-style hats, see when to replace a cowboy hard hat. For the rules, read OSHA hard hat requirements. More on the hard hats hub.
Sources
- OSHA 29 CFR 1910.135, Head protection
- OSHA 29 CFR 1910.132, PPE general requirements
- International Safety Equipment Association (ANSI/ISEA Z89.1)
Frequently asked questions
Do hard hats have an expiration date?
There is no legal expiration date, but manufacturers set a service life, usually counted from the date of manufacture stamped inside the shell.
How do I read the date on a hard hat?
Most hats have a dial inside the shell: the center number is the year and the arrow points to the month.
How often should a hard hat suspension be replaced?
Many manufacturers recommend about every 12 months, or sooner if it is damaged or worn.