Safety Helmet is a type of Helmet predominantly used in workplace environments such as industrial or construction sites to protect the head from injury due to falling objects, impact with other objects, debris, rain, and electric shock. Suspension bands inside the helmet spread the helmet's weight and the force of any impact over the top of the head. A suspension also provides space of approximately 30 mm (1.2 inches) between the helmet's shell and the wearer's head, so that if an object strikes the shell, the impact is less likely to be transmitted directly to the skull. Some helmet shells have a mid-line reinforcement ridge to improve impact resistance. The rock climbing helmet fulfils a very similar role in a different context and has a very similar design.

Safety Helmet colours:-Safety helmet colours on Build UK members' sites should adhere to the following colour scheme on all new (and existing, where practicable) sites:
White - for site managers, competent operatives and vehicle marshals (distinguished by the wearing of a different coloured high-visibility vest).
Black - for site supervisors.
Orange - for slingers and signallers.
Blue - for all other site visitors.

Are there any exceptions?
Network Rail's PPE standard requires only white and blue safety helmets to be used on site. 
Additional responsibilities - such as trained first aider or fire marshal - will be denoted by the use of stickers.
MIPS is the “Multi-directional Impact Protection System”, designed to reduce the rotational motion transmitted to the brain from angled impacts. During an angled impact, rotational motion can cause strain to the brain tissue, which may lead to severe brain injuries.
When you have suffered a concussion or even more serious damage to the brain, rotational motion to the brain is the most likely cause. MIPS’ added protection system has been proven to reduce the rotational motion when implemented in a helmet by absorbing and redirecting forces that could otherwise be transmitted to the brain.
The Brain Protection System (BPS) is found inside the safety helmet, generally between the comfort padding and the EPS (a high-quality foam used to reduce energy). At certain impact, the MIPS BPS can reduce harmful forces that may otherwise be transmitted to the brain.
Shipbuilders were the first workers to cover their existing hats with tar to protect their heads from objects falling off ships. Over the century, protective hats have been made of leather, steel, aluminium, fiberglass, plastic, and even steamed canvas held together by glue.
Today’s hard hats are composed mainly of polyethylene. Modern hard hats now may include features shipbuilders of yesteryear could never dream of such as: ventilation, face shields, ear muffs, visors, perspiration liners, lights, radios, or walkie-talkies. And, their evolution continues with the rise of safety helmets.

Safety Helmet Shift
When picturing a safety helmet, think rescue worker or outdoor sports like, rock climbing, skiing, cycling, and even sport kayaking. These helmets typically attach more closely to the head with built-in chin straps and have little to no brim around the edge. Their overall profile on the head is smaller.
Safety helmets have increased safety elements which is why they have mainly been worn by athletes in dangerous sports and rescue workers in hazardous situations. Inside the helmet there is protective padding, and chin straps that keep the helmet securely on the head.
Helmets Are Construction-Tough
For construction workers, safety helmets not only shield against falling objects, but certain models (Type II) can offer increased protection from impacts to the side and back of the head.
Type II Helmets and Hard Hats are designed to minimize lateral impacts to the head; either from off-centre, from the side or to the top of the head. For example, a blow to the head resulting from the sharp end of a side beam or I-beam.
In addition, chinstraps, whether on a helmet or hard hat, can provide increased safety during falls, trips, and slips by keeping head gear in place.

Safety Helmet Options and Accessories
Other attributes that make safety helmets safe include options like attachable visors, ear protection, and being equipped with or constructed from Hi Viz materials.

Type and Class
All head protection is assigned a “Type” and a “Class.” The Type refers to the level of protection from an impact, while the Class refers to the different levels of protection from electricity.
ANSI Type I Helmets are designed to reduce force as a result of impact to the top of the head
ANSI Type II Helmets are designed to reduce force as a result of impact to the sides or top of the head
The three classes of head protection include:
Class E (electrical) provides protection to withstand 20,000 volts
Class G (general) provides protection to withstand 2,200 volts
Class C (conductive) does not provide protection from electricity
A, a Type 1, Class C hard hat would be the standard worn by a construction worker not exposed to electrical hazards; a standard safety helmet would be categorized as Class C.
Barriers to Safety Helmet Domination
With all this positive news about safety helmets, what could hold back their full take-over of hard hats? One barrier is cost. Safety helmets are significantly more expensive than hard hats. A lost or misplaced hard hat is less painful to replace, monetarily speaking, than a safety helmet – which can be a stretch for smaller companies or individuals. However, they do last longer – up to 10 years in some cases. The need to purchase fewer safety helmets over the years could outweigh the initial costs.
Another challenge to embracing safety helmets on the job is worker preference. Hard hats are a longstanding symbol of the construction worker. Not only does the safety helmet have a different look than the traditional hard hat, it has a different feel. Some workers may feel uncomfortable wearing the sleeker design of the safety helmet. This may make the cultural shift difficult for some workers.
It’s possible that some workers switch to safety helmets while others continue to wear hard hats depending upon the type of work they are doing. Safety helmets could be required when working at heights or in situations where there is a higher risk of falling – while hard hats continue to be worn by workers at ground level, such as concrete finishers, flaggers, electricians, drivers, etc.
The implementation of more and more safety helmets means added benefits for workers, construction companies, and insurance carriers. Increased use of safety helmets means companies may have less workers out due to injury, less worker’s compensation pay-outs, and fewer claims.