1A rigid protective helmet, as worn by factory and building workers.You wouldn't send a brickie on to a building site without a hard hat....
There is a difference between a rule forcing people to wear hard hats inside a building site due to the risks of falling objects and refusing to let kids play conkers out of fear for their safety.
A wide range of additional tourist-friendly locations are being proposed for the Games, presumably so that visiting IOC members don't have to spend all their time standing on bleak building sites in hard hats and wellies.
1.1informalA worker who wears a hard hat.Many of the country's 6.3 million hard hats could find themselves out of work.
1.2North AmericaninformalA reactionary or conservative person.