Galvanised Steel: Why the Zinc Coating Is the Problem
Can you laser engrave or cut galvanised steel?
Not safely. The steel itself is fine on a fibre laser, but the zinc galvanising vaporises into fumes that cause metal fume fever — hours of flu-like fever, chills and nausea. Cutting is worse than marking, and the risk rises with every extra pass. The safe route is to strip the zinc from the mark area first, or use bare, uncoated steel.
Hides inWhere it turns up
Outdoor hardware, fence and gate fittings, ductwork, buckets and bins, structural brackets, anything with that dull mottled-silver 'spangle' finish, and much cheap imported steel stock.
InsteadSafe alternatives
Bare mild or stainless steel for fibre marking. If you must mark galvanised, mechanically remove the zinc coating from the mark area first and confirm bare metal.
If it happensAccidental exposure
Stop and ventilate immediately. Metal fume fever symptoms can appear hours later — if you feel feverish or unwell after lasering coated metal, seek medical advice and mention zinc/metal fume exposure.