Every hard hat label carries a Type number and a Class letter, and they answer two different questions — where the impact comes from, and how much voltage the shell insulates against. Here is the decoding, and what a crew should actually stock.
In a hurry — the picks (affiliate links — as an Amazon Associate I earn from qualifying purchases; the type/class decoding below)
| Full brim, general use | LANON full-brim HDPE |
| Stated Type I, Class E | antools full-brim (Z89.1 Type I Class E) |
| Cap style | Cap-style, 4-point ratchet |
| Yearly: MSA V-Gard suspension | Fas-Trac III 4-point, MSA 10148708 (search) |
| Crew / visitor 10-pack | Full-brim 10-pack (stated Type I Class E) |
OSHA's construction rule, 29 CFR 1926.100, requires head protection wherever there is a possible danger of head injury from impact, falling or flying objects, or electrical shock and burns — and it points to ANSI Z89.1 as the consensus standard the helmet must meet. The standard's two axes:
Practical notes crews get wrong: paint and aftermarket stickers can void some manufacturers' ratings — check the maker's guidance; wear the suspension as fitted (reversed only if the manufacturer rates it); and replace any hat that has taken a real impact, visibly damaged or not. Service life is set by each manufacturer — MSA's numbers for the V-Gard family are below.
Fits: the general-purpose full-brim — sun and rain off the neck, ratchet suspension (~700 ratings). Check the variant's stated Z89.1 type/class on the listing and label.
Fits: crews that need the Class E electrical rating stated plainly on the listing.
Fits: workers who won't keep a full brim on — the classic cap profile, lighter and less in the way. Verify the stated class before electrical work.
Fits: the gate box and visitor rack — same logic as visitor vests: "no hat, no entry" only works when spares exist.
The shell gets the attention, but the suspension — the headband and straps that hold the shell off your head — is on a much shorter clock. MSA, the maker of the V-Gard, says suspensions should be replaced after 12 months and shells used no longer than 5 years, both counted from the day of first use, not the manufacture date molded under the brim. MSA also says to inspect the hat each time you intend to wear it. Other makers publish their own intervals, so check the instructions that came with your hat.
Replacement suspensions are sold by helmet family. Match the helmet name on your shell to MSA's own fit list:
| Your MSA helmet | MSA replacement suspension (standard size) |
| V-Gard, V-Gard 500, V-Gard GREEN or SmoothDome | Fas-Trac III 4-point — part 10148708 |
| V-Gard 500 or SmoothDome, 6-point | Fas-Trac III 6-point — part 10153382 |
Fit lists from MSA's product pages for each part number. Write the swap date inside the shell so next year's replacement isn't a guess.
Fits (per MSA): V-Gard, V-Gard 500, V-Gard GREEN and SmoothDome helmets, standard size. The link opens an Amazon search: pick a listing with 10148708 in the title, since look-alike suspensions are sold for the same hats.
Fits (per MSA): V-Gard 500 and SmoothDome helmets, standard size.
Type I is rated for impacts to the top of the head — the classic North American hard hat. Type II adds lateral (side) impact protection, and is increasingly what GCs mean when they specify climbing-style safety helmets.
Class E ("electrical") shells are proof-tested to 20,000 volts. Class G ("general") is tested to 2,200 volts, and Class C ("conductive") — including most vented shells — has no electrical rating at all.
Immediately after any real impact, visibly damaged or not. Absent an impact, follow the manufacturer's service-life guidance. MSA's is no more than 5 years for the shell and 12 months for the suspension, counted from first use rather than the date code molded under the brim.
MSA says after 12 months from first use, or sooner if an inspection turns up wear or damage. The suspension is sold separately, so a sound shell inside its 5-year life only needs the suspension swapped.