Head injury accident is one kind of the major occupational accidents, particularly in the construction industry.
Every year many workers injured or are even killed as a result of head injury.

The main risks of head injury in the workplaces are as follows:

• where there is a possibility that a worker may be struck on his head by a falling or flying object.
• where a worker may strike his head against a protruded object or may be struck by a swinging object.

To effectively reduce the risks of head injury, an appropriate type of safety helmets should be provided.
The safety helmet selected should satisfy certain performance requirements including :

• Shock absorption,
• Resistance to penetration,
• And be adjustable to fit and make comfortable to the user.

What you might not know, however, is that different colour hats signify different things on site, letting workers know who is who and carrying out what role. Although this colour coding system differs from country to country and even within individual organisations, there are a few basic rules that can help you to identify workers from the colour of their hats.

What the colours mean :

• White
  Managers, foremen, engineers or supervisors usually wear white hats on site.
• Brown
  Brown hats are worn by welders and other workers with high heat applications.
• Green
  Green often signifies a safety inspector but can also be used by new workers on the site or probationary staff.
• Yellow
  Yellow is the colour for general labourers and earth moving operators.
• Blue
  Carpenters and other technical operators including electricians will normally wear blue hard hats, while orange is worn by road crews.
• Grey
  Grey is the colour often worn by site visitors. And if employees forget their hats or misplace them, there is often a nice bright pink helmet on site they have to wear in the meantime.

This colour coding system is a general and unwritten rule within the industry and certainly not hard and fast.
Some companies will not use the exact system mentioned above so it is worth asking before you start on any site.
Ultimately, although the colour coding system is very helpful and has potential safety benefits, any hard hat of any colour is better than none at all.