Final answer:
The main purpose of a hard hat's outer shell is to protect the wearer against impacts from objects, resisting penetration and distributing blunt forces. It is made from durable materials to mitigate head injuries. Safety standards such as OSHA and OHSA mandate the use of protective equipment, including hard hats, to minimize workplace hazards.
Step-by-step explanation:
The purpose of a hard hat's outer shell is primarily to protect against blows or penetration. Hard hats are designed to prevent head injuries by absorbing the impact from falling objects, or in the case of workers bumping into fixed objects, and distributing the force over a larger area. The outer shell is made of tough materials like high-density polyethylene or polycarbonate to resist penetration and deflect blows to the head.
Although they do assist in shock absorption, the main feature for this is often the suspension system inside the hat. Contrary to the suggestion that they provide 10 years of head protection, the effective lifespan of a hard hat depends on the conditions of its use and it is always important to follow the manufacturer's recommendations for replacement. The colors and markings on hard hats can sometimes be used to identify different roles on a jobsite, such as supervisors, but it is not the primary function of the outer shell.
Under OSHA's standards and the Occupational Health and Safety Act (OHSA), employers are required to provide appropriate personal protective equipment like hard hats to minimize exposure to workplace hazards, thereby ensuring the safety and health of their workers.