Hard hats are classified by two separate systems: type (which describes where on the head they protect against impact) and class (which describes how much electrical protection they offer). OSHA requires employers to provide head protection that meets the ANSI/ISEA Z89.1 standard, and every compliant hard hat is labeled with both a type and a class so you can match the helmet to the hazards on your jobsite.
Type I vs. Type II: Impact Protection
The “type” rating tells you which parts of your head the hard hat is tested to protect.
- Type I hard hats protect only the top of the head. They’re designed for blows that come straight down, like a falling bolt or tool. This is the traditional hard hat shape most people picture.
- Type II hard hats protect the top and sides of the head, including the temples and the back near the base of the skull. They use thicker padding or foam liners to absorb lateral impacts. If there’s a risk of bumping into low beams, swinging loads, or side-impact hazards, Type II is the appropriate choice.
Class G, E, and C: Electrical Protection
The “class” rating describes how much electrical voltage the hard hat can withstand. This is the classification system most people mean when they search for “OSHA classes” of hard hats.
- Class G (General) hard hats are rated for up to 2,200 volts. They provide basic electrical protection and are the most common class used in general construction.
- Class E (Electrical) hard hats are rated for up to 20,000 volts. These are designed for workers near high-voltage lines or equipment, such as utility lineworkers and electricians.
- Class C (Conductive) hard hats offer no electrical protection at all. They’re typically lightweight or ventilated helmets used where electrical hazards are not present. Because vents and metal components can conduct electricity, Class C helmets should never be worn around energized equipment.
Older Letter Designations
Before the current G/E/C system, the 1986 version of the ANSI standard used the letters A, B, and C. Class A corresponds to today’s Class G, and Class B corresponds to Class E. Class C remained the same. You may still see the old A/B/C labels on literature or legacy equipment, but any hard hat purchased today should carry the updated G/E/C markings. If a hard hat in your workplace still references the 1986 standard, it’s almost certainly past its useful life and should be replaced.
What OSHA Actually Requires
OSHA’s head protection standard (29 CFR 1910.135) has two core rules. First, employers must ensure workers wear a protective helmet in any area where falling objects could injure the head. Second, any worker near exposed electrical conductors that could contact the head must wear a helmet designed to reduce electrical shock hazard, which means Class G or Class E depending on the voltage involved.
The helmets themselves must comply with one of three accepted editions of the ANSI Z89.1 standard: the 1997, 2003, or 2009 version. The most current industry standard is ANSI/ISEA Z89.1-2014, reaffirmed in 2019. OSHA also allows head protection that an employer can demonstrate is equally effective, even if it doesn’t carry the ANSI label.
How to Read the Label Inside Your Hard Hat
Every compliant hard hat has markings printed or molded inside the shell. At a minimum, you’ll find the manufacturer’s name, the ANSI Z89.1 standard it was tested to, the type (I or II), the class (G, E, or C), and the date of manufacture. Some helmets also carry optional markings that indicate additional testing:
- Reverse donning arrow: The helmet can be worn backwards and still meet performance requirements.
- LT: Tested for performance in low temperatures (down to -30°C).
- HV: Meets high-visibility color requirements.
The date of manufacture matters because hard hat shells degrade over time from UV exposure, heat, and chemical contact. A general guideline is to replace a traditional hard hat shell after five years of service, while newer safety helmets (with chin straps and integrated eye protection) can last up to ten years. Suspension systems inside the hat wear out faster and typically need replacement every one to two years, or sooner if they show fraying, cracking, or loss of elasticity.
Stickers, Paint, and Modifications
OSHA does not outright ban stickers or paint on hard hats, but there are real risks. Paints, thinners, and solvents can chemically attack the shell material, weakening it in ways that aren’t visible. Stickers can hide cracks and damage that you’d otherwise catch during a quick inspection. And any coating applied to a Class G or Class E hat could compromise its electrical resistance.
The practical rule: follow the manufacturer’s specific instructions on what adhesives and paints are safe to use. If you can’t confirm that a modification is approved by the manufacturer, or if stickers cover so much of the shell that you can’t inspect it for damage, the hard hat may no longer meet the ANSI standard it was originally rated for. Some manufacturers sell clear or translucent stickers specifically designed to allow visual inspection underneath.