Start with the standard. EN 397 is the European standard for industrial safety helmets, and the marks after it show optional tests that Delta Plus lists: MM for molten metal splash, LD for lateral deformation (squeeze from the sides), a temperature range such as -30°C to +50°C, and 440 V AC for short accidental contact with live conductors. For electrical work, look at the helmets also stated to EN 50365 Class 0, the European standard for electrically insulating helmets used on low voltage installations: ONYX, DIAMOND V, QUARTZ UP III, SUPER QUARTZ and QUARTZ I. A bump cap to EN 812, such as the AIR COLTAN, only guards against knocks on fixed objects and does not replace a helmet where things can fall.
Then the shell and the fit. QUARTZ UP IV, QUARTZ UP III and QUARTZ I use UV-resistant high density polypropylene, DIAMOND V and ONYX use ABS, and SUPER QUARTZ uses ABS-PC that Delta Plus tested from -30°C to +150°C for steel industry work. QUARTZ UP IV and QUARTZ I have adjustable ventilation. The One-D Rotor knob (ONYX, QUARTZ UP IV, QUARTZ UP III) sizes the helmet with one hand, DIAMOND V and SUPER QUARTZ use a push button, and QUARTZ I and ZIRCON 1 are adjusted by hand; all cover head sizes 53 to 63 cm.
If the job also needs face protection, the ONYX has a retractable visor built in, stated to EN 166 and EN 170 and to arc fault Class 1 under GS-ET 29, with a spare visor (VISONYXPR) and spare harnesses (HARNESS O) listed. For other helmets, the Delta Plus VISOR HOLDER face shield holder fits ZIRCON, QUARTZ and DIAMOND helmets. Prices are on request: call or WhatsApp +91 92440 89060.