The Construction of a Cycling Helmet

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Xray of skull with brain on black background.When we buy a cycling helmet, we are buying to meet our need for SAFETY, to protect our most valuable asset – the very fragile person residing inside the skull, distributed around the mushy brain – the most complex thing we know of in all the universe. Our safety depends entirely on adequate cycling helmet construction.

The brain weighs around three pounds and fits securely inside the skull; it’s covered with a protective membrane called the dura mater and surrounded by a cushioning fluid called cerebrospinal fluid (CSF).

The brain is attached to the spinal chord, so it’s not free-floating or hanging in the skull. Second there are many different layers of protective covering between the brain and the skull that cushion and hold the brain in position. However, the fast sudden movement of the head caused by rapid acceleration in a car or bike accident causes the brain to ‘crash’ against the interior of the skull which can causing brusing, trauma and even death.

To reduce the effects of such an impact, a bicycle helmet must absorb much of the impact and redirect the energy generated away from the wearer’s head. When a properly designed bike helmet takes an impact, it does exactly this and part of its structure essentially collapses as it absorbs energy; this is why a helmet MUST be replaced after an accident – it has done its job and cannot provide further protection. So what does a properly constructed, safe helmet look like?

Safety Is Key In The Construction Of A Cycling Helmet

Recent statistics show approximately a thousand people die each year in bike accidents in the US. Further, there are a half-million E.R. visits due to bike-related injuries. Statistics show the most serious accidents occur among teenagers and men over forty. Further, more accidents occur in the city and in areas other than intersections. A helmet offers the protection cyclists need. Indeed, wearing a properly designed and certified helmet provides significant protection to cyclists from brain and head injuries. It is amazing how much design work goes into manufacturing the Best cycling helmets!

How Does a Helmet Work?

This is from a great site called bicycle source:

“A bicycle helmet reduces the peak energy in a sharp impact. This requires a layer of stiff foam to cushion the blow by crushing. Nearly all bicycle helmets do this with expanded polystyrene (EPS), the white picnic cooler foam used to protect eggs and computers. Once crushed, the foam does not recover. Spongy foam is added inside for comfort and fit. Another foam, expanded polypropylene (EPP), does recover, but its use is spreading slowly. It may have some undesirable “rebound.” An stronger EPS called GECET appeared in 1992 and is widely used now. A third foam called EPU (expanded polyurethane) is used for helmets made in Taiwan. It has a uniform cell structure and good crush without rebound, but is difficult to manufacture and not used much in the U.S.”

Note: The helmets we sell on PedalDeals are mainly of the EPS type – proven and tested!

Types Of Helmets

There are three types of helmets: recreational, road bike and mountain bike.

Recreational helmets have a visor and are used for all types of cycling. Further, this type of helmet is worn by skaters and skateboarders.

A road bike helmet is made for speed. They are well-ventilated, light-weight and have an aerodynamic design. Most road bike helmets do not have visors.

Finally, mountain bike helmets are designed to give the cyclist lots of breathing room. Mountain bike enthusiasts travel over dangerous ground and therefore, the helmet is designed with a snugger fit and the helmet protects the back of the head. Some mountain cyclists prefer helmets with full-face shields, and the shield must protect the eyes from flying rocks and dirt.

helmet interior eps

Helmet Construction

Construction of a Cycling Helmet is crucial to safety. Most manufacturers use the same design. Manufacturers use lightweight EPS for the inner shell. The foam is covered by a layer of polycarbonate. Additionally, the shell and foam inner layer should lock together.

The ideal helmet is light and safe at the same time. The EPS foam protects the head in a crash by absorbing the impact. Interestingly, most helmets are destroyed in impact collisions. This is because the foam absorbs by compressing and does not bounce back. Additionally, the shell withstands punctures and allows the helmet to slide on impact. This ability to slide protects the head and neck. Experts recommend buying a new helmet after an accident.

Some manufacturers offer the Multi-Directional Impact Protection System (MIPS.) This technology allows the foam liner to rotate during a crash. The rotation around the head protects the brain from injury.

Testing of Bike Helmets

Basically, testing of cycling helmets is all about the “g.” A g is the amount of gravity exerted on a cyclist when they fall. Bike helmet safety has been studied for years. Instruments inside the helmet measure the g force. After testing, experts believe cyclists are safe if the g force is under 300 g. Most helmets on the market meet the test. Interestingly, helmets are tested by dropping them upside down on an anvil. Helmets are usually dropped between three to six feet.

However, this is not the only test for bike helmets. Here at PedalDeals, our Certified Helmets (which are clearly identified as such), meet a range of standards for impact, fit, visibility and more. We have included the details of these standards at the end of this post.

Getting A Good Fit for your Cycling Helmet

The right fit is key to Cycling helmet safety. Every properly advertised helmet will tell you what size heads it fits – in inches or cm or both – almost all helmets are now adjustable. Measure around the largest part of the head starting just above the eyebrows. Helmets start at extra-small for people who measure under 20 inches. The size range goes to extra-large for heads measuring 24.7 inches and above. Kids helmets usually come in one-size fits all. Additionally, straps that are made correctly are a must. The cyclist must be able to buckle and unbuckle the straps with little effort.

Cycling Helmet Care

Helmets can get pretty dirty. However, owners are advised not to use harsh chemicals to clean them. Soap, water and a soft cloth will do the job. Any removable pads are washable. Further, helmets should not be kept in areas with high temperatures like attics. Heat can damage key helmet parts. Cyclists should not wear helmets they think are damaged. Cyclists who have not been in an accident should buy a new helmet every five years. Consumers who need to buy a helmet should shop around. It is one of the most important purchases they will make. Try the helmet on and make sure it fits properly. Taking these precautions could save your life.

White Certified Helmet

Appendix: Standards for the PedaldDeals Certified Helmet

CPSC 16 CFR 1202

1203.2 Purpose and basis.
The purpose and basis of this USA standard is to reduce the likelihood of serious injury and death to bicyclists resulting from impacts to the head, pursuant to 15 U.S.C. 6001-6006.

General Requirements

(1) Projections. All projections on bicycle helmets must meet the construction requirements of § 1203.5.

(2) Labeling and instructions. All bicycle helmets must have the labeling and instructions required by § 1203.6.

(3) Performance tests. All bicycle helmets must be capable of meeting the peripheral vision, positional stability, dynamic strength of retention system, and impact-attenuation tests described in §§ 1203.7 through 1203.17.

BS EN 1078:2012+A1:2012

This European Standard specifies requirements and test methods for helmets worn by users of pedal cycles, skateboards and roller skates.

Requirements and the corresponding methods of test are given for the following:

  • construction, including field of vision
  • shock absorbing properties
  • retention system properties, including chin strap and fastening devices
  • marking and information

Certificate Extracts

SGS Report Front Page 2

SGS REport Front Page

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