Hard Hat Types and Class Standards
According to the Occupational Safety & Health Administration (OSHA), a hard hat must be worn “when working in areas where there is a potential for injury to the head from falling objects.” In addition, a hard hat must also be worn in working areas where there is the risk of exposure to electrical conductors that can potentially contact the head. In these types of environments, specially designed protective helmets are required in order to counteract the dangers of electrical shock hazards. Hard hats that are considered to be “OSHA approved” meet the minimum criteria established by the American National Standards (ANSI) and the International Safety Equipment Association (ISEA), in accordance with the most current ANSI/ISEA Z89.1-2009 standard.
If a hard hat is necessary the next step is selecting the most appropriate hard hat for your work environment. ANSI divided protective helmets into different types and classes. A hard hat type indicates the designated level of impact protection, while a hard hat class indicates the degree of electrical performance. The sections that follow explain the various types and classes of hard hats in further detail.
Hard Hat Types
Hard hat impact protection is divided into two categories: Type I and Type II.
Type I Hard Hats are intended to reduce the force of impact resulting from a blow only to the top of the head. This form of impact, for example, may result from a hammer or nail gun falling from above. Type I hard hat is the MSA V-Gard Hard Hat.
Type II Hard Hats are intended to reduce the force of lateral impact resulting from a blow which may be received off-center, from the side, or to the top of the head. This form of impact, for example, may result from contact with the sharp corner of a side beam. Type II hard hats, such as the MSA Super V® Hard Hat , are lined on the inside with a thick high density foam and suspension.
According to ANSI/ISEA Z89.1-2009 and Canadian CSA Z94.1-2005 standards, hard hat electrical performance is divided into three categories: Class E, Electrical; Class G, General, and; Class C, Conductive.
Class E (Electrical) Hard Hats are designed to reduce exposure to high voltage conductors, and offer dielectric protection up to 20,000 volts (phase to ground). This amount of voltage protection, however, is designated to the head only, and is not an indication of voltage protection allocated to the user as a whole. The MSA Topgard® Hard Hat is an example of a hard hat used by utility workers who are commonly exposed to high voltage environments on a daily basis. Formerly associated with a "Class B" rating, Class E hard hats may also be considered to have a Class G (General) rating, as their increased level of voltage protection surpasses the (lower) required standards of the Glass G testing procedure.
Class G (General) Hard Hats are designed to reduce exposure to low voltage conductors, and offer dielectric protection up to 2,200 volts (phase to ground). As is the case with Class E hard hats, this amount of voltage protection is designated to the head only, and does not account for voltage protection allocated to the user as a whole. The MSA Skullgard Hard Hat is an example of a Class G hard hat commonly worn by iron workers who require a certain degree of dielectric protection. Formerly categorized as "Class A," the Class G hard hat is the most commonly sold.
Class C (Conductive) Hard Hats differ from their counterparts in that they are not intended to provide protection against contact with electrical conductors. On the contrary, Class C hard hats may include vented options, such as the MSA V-Gard 500 Hard Hat , which not only protect the wearer from impact, but also provide increased breathability through their conductive material (such as aluminum) or others.
How can I identify the type and class of my current hard hat?
It is important to know that all hard hats that adhere to ANSI/ISEA standards contain a label of certification on the inside of the hard hat shell. This label identifies the type and class standards the hard hat was designed to meet. If your current hard hat label is missing or is no longer legible, it is recommended that you replace your hard hat as soon as possible