The helmet is used to prevent injury from anything falling from above. In the case of road works there is frequently heavy machinery digging, plus you will have drills breaking up road surfaces. The head protection also acts to protect the head in case of collision with hard surfaces of any kind. They also keep you head dry to a degree as the weather in the UK can be one of the wettest.
The H and S Regulations also require all trades to wear head protection on any building site. They do not consider roads as anything different to a building site. That way they cover wide building environment with one statement and stop potential loop holes in regulation. Hats are normally coloured in high visibility colours like white, yellow and bright red. This will allow machinery drivers to have a chance of seeing someone who may be in ditch or hole when they excavate.
Helmets can only protect your head. so if your balls get hit the helmet does not protect them.
They wear spacesuits, including helmets, to protect themselves from the outer space environment. It is basically a simple space craft.
Bicycle helmets are designed for safety first and foremost. The hard shell and padded inside protect the head from injury in the event of a fall or accident on a bicycle.
the helmets protect them a lot
Helmets?
Storm Troopers wear armor to protect them from blaster bolts. The helmets protect their heads.
to protect their faces
Helmets.
Firefighters in the UK (and everywhere else) wear helmets to protect themselves. The color is chosen by the department that they are employed by, and can often be different colors to distinguish ranks among those in the fire service.
To protect the head in case of impact.
the body protect itself when such an accident happen by it's recovering materials that can protect it from any accident .
Same reason as helmets have always been, and are used - to protect their heads against impact.