THE RIGHT FIT AND CARE
Helmets only work if they are properly worn and maintained. As with shoes and work boots, it is difficult, if not impossible, to squeeze into a helmet that is too small. But one that is way too big will have its own problems. A helmet not only needs to fit properly, it also needs to be properly secured.
Whether wearing a work safety helmet or a combat helmet, it should be snug, with the chinstrap holding it in place. Helmets shouldn't be cocked to the side (style comes a distant second after protection when helmets are involved). Fortunately, many modern helmets have removable pads that help ensure the perfect fit. These can also improve comfort when wearing the helmet for extended periods.
When helmets aren't being used, they should be properly stored with other vital equipment and inspected regularly. In addition to dings and scratches, helmets should be checked for insects and cleaned so they don’t collect mold or dirt. Removable pads should be replaced before they interfere with a proper fit or completely wear out.
Today's modern combat and safety helmets are made from Kevlar, Twaron or similar synthetic fibers. They don't normally break down quickly. However, as with so many other materials, exposure to UV radiation from sunlight for extended periods can be an issue. For these reasons, a cover is recommended (this is the reason the military generally uses helmet covers).
Specialty safety helmets should also be inspected. In addition, a backup helmet or two is recommended, because once a helmet is damaged, it should be removed from regular use.