EN 397 vs ANSI Type I and II, shell materials, suspension systems, expiry rules and the inspection points that DOSHS and site inspectors check on helmets.
Download Article (PDF)Safety helmets save lives on Kenyan construction sites every day — and counterfeit or expired helmets claim them. Choosing a helmet is a 15-minute decision with a decade-long consequence. Here is how to do it properly.
Step 1: Check the standard
Demand helmets tested to a recognised standard:
- EN 397 — the European industrial helmet standard: impact, penetration, flame resistance and electrical performance.
- ANSI/ISEA Z89.1 Type I — protects against vertical impact only.
- ANSI Z89.1 Type II — adds lateral (side) impact protection.
The standard mark should be moulded into the shell or printed on a permanent label. No mark? No purchase. The 3M Vanguard helmet and other major brands print their certification directly on the shell.
Step 2: Choose the right shell material
- HDPE (high-density polyethylene) — the affordable workhorse; tough, UV-resistant, good for most sites.
- ABS — strong, with better resistance to chemicals and solvents; slightly heavier.
- Fibreglass composite — best electrical insulation and heat resistance; used for electrical and foundry work.
- Polycarbonate — lightweight and impact-resistant; premium option.
Step 3: Understand suspension and classes
The suspension (the cradle inside) absorbs impact energy — it is as important as the shell. Check for:
- Adjustable headband with a clear size range (typically 52–62 cm).
- Easy-height adjustment (pin-lock or ratchet).
- Chin strap option for tasks with leaning or inverted work.
- Ventilation for Kenyan heat, without compromising the standard.
For electrical work, choose helmets tested to the relevant electrical class. Add accessories when needed: face shields, ear muffs and helmet-mounted lamp brackets must be approved for the helmet model.
Step 4: Fit it correctly
Fit determines protection:
- The helmet should sit level, roughly one finger-width above the eyebrows.
- It should not move when you shake your head.
- The chin strap, where fitted, must be snug.
- Wear it at all times in the designated area — not on the back of the head or the passenger seat.
Expiry and replacement rules
Helmets have a service life — usually 2–5 years from manufacture depending on material and exposure. Replace immediately after:
- Any significant impact (even if no crack is visible).
- Visible cracks, dents, or deep scratches.
- UV discolouration or chalky texture.
- Chemical or paint damage.
- Deteriorated suspension (torn cradle, cracked adjuster).
Never paint, drill or solvent-clean a helmet shell — this voids its certification.
Buying tips for Kenyan buyers
- Buy branded helmets from authorised stockists with certification documents per batch.
- Store helmets out of direct sunlight between shifts.
- Keep one spare per 10 helmets for visitors and replacements.
- Record batch numbers for traceability in audits.
Browse certified industrial safety helmets from 3M, MSA, Karam and Delta Plus, or request site-wide pricing.
