Fighfighters helmets were introduced in the 1830's to help protect them against falling cinders and debris
The firefighter's helmet was originally made of leather, then brass, then cork, then steel, then aluminium, then thermoplastic, then a composite of all sorts of materials each adding different protection against hazard a modern firefighter might face
In the 1930's as electricity became a hazard so brass was abandoned and cork helmets with a rubber coating were introduced as this one.
Metal military-style helmets came back in world war II
Helmet at least in the UK are yellow, but some countries the colour is used to denote rank in the fire service.
This helmet was purchased from an auction site, is very tatty some of the finish as worn off, but it was a bargain purchase.