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Safety Hard Hat

ANSI Standard Z89.1-2003

SCOPE AND APPLICATION

This standard describes types and classes of protective helmets, testing and performance requirements, including safety requirements for authorities establishing codes and regulations. Minimum performance requirements are outlined for impact forces, penetration and electric shock protection. It is noted that the protection rating reduces the amount of impact and penetration but will not provide complete protection against severe impact. The helmets should be effective against small tools, small pieces of wood, bolts, nuts, rivets, sparks and similar hazards but should not replace good safety practices and engineering controls. Helmets that are designed with style in mind may not meet the testing requirements.

DEFINITIONS

  • Apex

    point on outer surface of the shell coincident with the vertical axis of the
    head form when mounted in the as-worn position according to
    manufacturer’s specification.

  • Dynamic Test Line (DTL)

    a test line used as a boundary for conducting impact energy
    attenuation and off-centre penetration tests.

  • Midsagittal plane

    a longitudinal plane perpendicular to the basic plane which passes
    through the vertex and geometrically bisects the head.

  • Position index

    a perpendicular distance as specified by the manufacturer from some
    point on the helmet to the basic plane where the helmet is seated on
    a reference head form.

  • Suspension

    portion of the harness which is designed to act as an energy absorbing
    mechanism. It may consist of crown straps protective padding or
    similar mechanism.

Headwear Classification

Headwear Classification is categorized in terms of impact type and electrical class.
All helmets shall meet requirements for impact Type 1 or Type 2

  • • Type 1 is for risk of impact is to crown only
  • • Type 2 is for crown and sides of the head.

Electrical classes, G, E or C further categorize each Type (1 or 2). The three classes E, G or C refer to the electrical ratings.

  • 01
    G—General usage

    Recommended for nearly every workplace. G-class hard hats protect against impacts and blows, resist voltages up to 2,200 volts.

  • 02
    E—Electrical trades

    Designed to resist impact, penetration, and protection against electric shock from high-voltage electrical conductors. In experiments, E-class hard hats resisted up to 20,000 volts from a ground connection. E-class helmets contain no metal and are typically made of high-density polyethylene and polycarbonate, with no holes, fasteners or metal. The E-class helmets’ suspension is made of vinyl, leather and/or nylon and resists electrical shocks. These are suitable for people who work in: transportation (railways, specifically), mining, forestry, manufacturing, construction & industrial trades. An E-class hard hat should be worn anytime work is done near an area that could expose you to active conductors or high-voltage electrical loads.

  • 03
    C—Conducting headwear

    Only C-class hard hats are ever made with aluminum, and they have no electrical rating. C-class hard hats aren’t meant to protect from electrical conductors, and may even have ventilation to provide extra comfort and breath-ability.

WHY DO HARD HATS EXPIRE?

The reason hard hats expire is pretty simple—They become less effective over time.

Since hard hat manufactures must meet safety standards, they are created to be extremely durable—However, they do not last forever. Depending on your work environment,your hard hat might need to be replaced at different rates.

Things that can affect how long your hard hat will last include:

  • Sunlight exposure
  • Temperature extremes
  • Chemical exposure
  • Sweat, liquids, and other substances coming in contact with your hard hat
  • Daily vs. occasional use

Things to look for in daily inspections:

  • Cracks, dents or cuts in the hat’s shell
  • Cracks or tears in the hat’s suspension
  • Cut or frayed suspension straps
  • Chalky, dull or crazing pattern on the outer shell
  • This can be a sign of damage sustained by heat, sunlight or chemical exposer.

The best way to determine if your hard had requires replacement is through daily inspections. These should be performed before each use.

Remember, the suspension of your hard hat is actually just as important as the outside (known as the shell). Hard hats have an inner layer that provides shock absorption
—Without this, your hard hat can actually do more to damage your head than save it.

If your hard hat is showing signs of any of these things, it should be replaced and disposed of, to avoid further use.

WHY DO HARD HATS EXPIRE?

Most hard hats will include manufacturer’s replacement recommendations. For example, 3M hard hats come with a suggestion to replace the hat’s suspension after 2 months of use and the shell every two to five years of use.

Be sure to take note of your hard hat’s replacement recommendations and ensure you are keeping on top of replacing the necessary parts in a timely manner. However, no matter how long in the future the replacement recommendation date is, you must continue to perform inspections before each use, as these recommendations should ONLY be followed if your hard hat shows no sign of expiry before then.

It is very important to remember that if your hard hat sustains an impact of any kind, dispose of it immediately, even if there is no visible damage. Impacts can cause the materials to become weakened, and even if there’s no visible damage, it may no longer be able to provide the same level of protection.