Motorcycle helmet

A motorcycle helmet, safety helmet officially, colloquially called helmet is part of protective clothing for motorcyclists and protects the head in a traffic accident from life-threatening injuries. Wearing a helmet is a legal requirement for motorcyclists in most countries.

Background

A motorcyclist is against motorists increased risks exposed because

• A motorcycle does not have a crumple zone has,
• Conditions of low grip conditions (moisture, dirt), there is an increased risk of falls and worse braking performance,
• Its speed is slightly underestimated by other road users,
• He has a larger blind spots than a car driver,
• He can dodge less well at speeds from about 30 km / h obstacles as a motorist.

For these reasons, safety helmets are worn by motorized two wheelers usually. Decrease according to a study in road accidents, the rate of craniocerebral traumas of motorcyclists by about 70% and the mortality by about 40%.

Regulations

Wearing a helmet is a legal requirement for motorcyclists in most countries, in Germany and most other European countries also apply to drivers of mopeds and scooters.

Protective helmet law for motorcyclists is the Federal Republic of Germany since 1976 (according to DIN 4848 ), in the former GDR also since 1976 ( according to traffic regulations ). 1980, a caution money when driving without a helmet ( driver and passenger) has been introduced. On 1 January 1990, the former DIN 4848 has been replaced by the ECE -22 standard. This provision was designed to work with helmets that have not been tested according to ECE, in the Federal Republic are permissible as long as they are suitable because of its design as a protective helmets by two exceptional regulations.

Construction

Types

• Helmets have a fixed chin and a fully lockable visor. They offer their design the best protection with minimum weight and are therefore used in motorcycle racing. Modern helmets usually have a weight of less than 1.5 kg. The chin strap of the helmet is often closed by a so-called double-D, but are also a number of quick-release fasteners for use.

• Flip-up helmets are a variation of the full-face helmet, in which the solid chin folds up. The protective effect is generally considered compared to full face helmets as something less, and the weight is slightly increased. Flip-up helmets facilitate removal of the helmet after an accident, they are also particularly recommended for eyeglass wearers and meet the current helmet standards.

• Motocross helmets are now full-face helmets with greater distance from the chin to have a helmet-mounted screen, and are well ventilated. You are without a visor, but be worn with motocross goggles.

• Enduro Helmets are full face helmets with the features of motocross helmets, but other than these are not tuned to the sports use, but on touring capabilities, which in addition to a smaller and thus less wind -prone screen ( usually removable) also means a controllable ventilation and the possibility they selectively to drive with visor or motocross goggles.

• Half-shell helmets, open face helmets also called, have no fixed jawline. There are versions with verbautem visor or sun visor, but also half-shells with a thermoformed visor and a little further drawn to the front pages, which are commonly referred to as 3/4 helmets. Half-shell helmets have to meet the ECE standard, protect the forehead, ears and neck. The so-called Brain Caps, whose helmet shell protects only the area above the ears and neck, this condition is not meet, they are therefore sometimes not recognized as protective helmets in accordance with the statutory provisions. Popular half-cup half helmets are especially among drivers of classic bikes in order to clarify their identification with the spirit of the times.

• Multi helmets are helmets with redevelopment potential, mostly the to remove the chin bar, where they can be used as a full face or open face helmet optional.

Materials of Construction

The helmet shells of two different groups of materials ( plastics) are divided Coarse made ​​:

• Thermoplastics ( eg ABS, polycarbonate, polyamide) These plastics are easily shaped under heat and are usually produced by injection molding. The advantage of these materials is that these easy to produce in large quantities and thus are favorable. The disadvantage is the rapid aging of the helmet shell in uncoated state, in particular by ultraviolet radiation, which makes a relatively fast renewal of the helmet is required.

• Thermosets and composites ( with glass (GRP), carbon ( " carbon" ), aramid or polyethylene fiber reinforced plastic. ) This plastic composites can be produced only in the laminate consuming process. They are brittle and not easily malleable, but stiff and unbreakable. Thus, these helmets are very stable, lighter but just as protective qualities and comparatively expensive, but the price level is also decreased significantly in recent years. In racing, they are used for their protective properties exclusively. Thermosets age less quickly, which the helmet shell brings a long life with good care.

The energy absorbing material inside the helmet is usually made ​​of foamed polystyrene.

Visors

There are now in the field of full-face helmets and open face helmets, a wide range of helmet manufacturer at different visors. Usually they consist of polycarbonate plastic, also known under the brand name Makrolon (Bayer) or Lexan (SABIC ), which for a clear plastic is very tough and impact resistant and also does not splinter. Many visors today are scratch resistant, ie, they are coated with a durable clear coat. However, this does not tolerate polish or aggressive cleaning agents.

Helmet visors tend (especially in rain) for shoeing. This trend means that many helmets over one position, in which the visor is almost closed so that additional fresh air to prevent fogging, while barely able to penetrate water. On the market there are also visors, which have been factory-fitted with a permanent anti-fog coating, which is, however, also sensitive. Other manufacturers offer anti-fog additional interior visors. Furthermore, look for commercially available anti-fogging agent application, which can be applied retroactively. Other components such as deflector, which direct the exhaled air down, the fog may also reduce.

There are different types of sights:

• Clear vision scopes: The most common type of visors, they are the standard for common types of helmets. You must have for road traffic over an E-mark.
• Mirrored and tinted lenses: Mirrored and Tinted visors are available in different colors and tint degrees, they mitigate the advantage of sunlight and thus prevent glare of the motorcyclist. Also tinted visor must have an e-mark for road transport and may be used under good weather conditions only during daylight hours. Use at night is prohibited and also dangerous, because visibility is greatly restricted. With a disregard for this prohibition is to face legal consequences and in case of accident compensation claims with the insurance company.
• Anti-fog visor ( Pinlock visor ): Here is a smaller visor via plastic pins or bonded directly mounted inside the main sights. The thin insulating layer of air that is created by prevents fogging of the visor. Disadvantages are, however, that the smaller inner visor can not prevent fogging of the edge region of the main visor, and can that the peripheral edge and the fortifications in sight disturb or irritate the driver.
• Additional sun visors: now being offered by various manufacturers helmets, which apart from the transparent visor via an additionally mounted, tinted visor that can be operated while driving. This is either attached as a second visor just in front of the eyes inside and can be operated by a switch from the outside, or is it a smaller visor that is mounted externally on the transparent visor and can be folded down when required. Since these can be operated while driving, the motorcyclist can react while driving to changing light conditions.
• Plug- visors: This is a comparatively narrow multilayer plastic part with light filter film, which is sandwiched between the helmet interior and the helmet shell. In the event of a sudden glare of the driver lowers his head and looks reflexively doing through the tinted glare protection. The hands stay on the handlebars and do not need a lever or similar button. The anti-glare fits most helmets without swiveling sun visor. When sitting upright, the eyes in the shadow cast by the sun visor stay relaxed. The helmet retains the ECE approval and may be driven in the dark.
• Heizvisiere: There is also Heizvisiere in which fine wires generate heat and thus prevent fogging permanently. Through a spiral cable and Abreißstecker the visor is connected to a power socket. With a Heizvisier you in cold and wet with a completely closed visor unimpaired vision. These visors are only available for a few helmets.

Safety standards

The current ECE standard 22/ 05 for helmets defines the following safety criteria when considering that:

• Size and shape of the damper shell
• Chemical resistance of the outer shell,
• Shock absorption values ​​at individual points through the drop test,
• Gooping especially in the small sizes,
• Carrying capacity of the chin strap and its hedging
• Load capacity of the chin strap closure,
• Size of the field of view,
• Penetration resistance of the visor, the visor tint.

When testing according to ECE 22 /05 additionally apply:

• Reduction of the currently valid limits for head lag and HIC (Head Injury Criterion) by 10%. Thus, the collision rate between the head and impacting object is set higher, resulting in a higher safety margin is created,
• Chin fee, examination of the chin part damping,
• Measuring the rotational acceleration ( outer shell )
• Visor tint, up to 50% Tint: only day use with labeling,
• ECE - label must be sewn with plastic wrap,
• Chinstrap backup as before, but not for TRIAL helmets

International are various other standards and testing institutes in use, such as:

• ACU (Auto Cycle Union ), United Kingdom
• AS / NZS 1698 ( "joint Australian / New Zealand Standard " ), Australia and New Zealand
• BSI 6658 (British Standards Institution ), United Kingdom
• CMVSS (Canada Motor Vehicle Safety Standards), Canada
• CRASH (Consumer Rating and Assessment of Safety Helmets ), Australia
• CSA CAN3 - D230 - M85 (discontinued, Canadian Standards Association ), Canada
• DOT FMVSS N º. 218 ( Department of Transportation), USA
• GOST R 41.22-2001 ( ГОСТ Р 41.22-2001, based on the ECE 22.05 ), Russia
• ICC ( Import Commodity Clearance ), Philippines
• IS 4151 (Indian Standard), India
• JIS T 8133:2000 ( Japanese Industrial Standards), Japan
• NBR 7471 (Norma Brasileira ), Brazil
• SHARP (Safety Helmet Assessment and Rating Programme), United Kingdom
• Snell M2005 & M2010 ( Snell Memorial Foundation), USA
• SNI ( Standar Nasional Indonesia ), Indonesia
• TCVN 5756:2001 ( " Tieu chuan Việt Nam ", Institute: QUATEST 3), Vietnam

Function and handling

Modern helmets are designed so that they convert them using a force, such as a blow in deformation energy. The crucial factor is less the material of the outer shell, but more the quality of the interior padding (usually polystyrene foam) that sits between the outer shell and lining. This layer is the only compressible part of the helmet, it takes over the impact the actual attenuation. The helmet shell distributed in any impact, the forces acting on the largest possible area and is elastically deformed; then it returns to its original shape. In contrast, the polystyrene layer undergoes plastic, ie permanent deformation.

Through this permanent deformation of the helmet can not protect the head by damping. Therefore it is recommended not to use a helmet after an accident or the manufacturer to send for review, even if only slight or no visual damage is evident.

Without closed chin strap of the helmet does not have sufficient protection, as it can break loose in an accident from the head. Even a damaged helmet ( dents, cracks or holes in the outer shell, after strong pressure or tensile forces, after falls from a low height also ) may offer a reduced protective effect. Flip-up helmets may be used generally only in the closed state, driving with folded up chin part is permitted only with helmets, in which the chin part can be completely pushed behind the helmet and have an additional examination as jet helmet.

Helmet decrease after an accident

In an unfortunate motorcyclist who is unconscious, the decrease of the helmet is imperative to avoid the risk of suffocation. The control of breathing and any necessary life-saving emergency measures may only be made if the helmet was removed. However, care must be taken to stabilize the cervical spine. Even when not unconscious patients, if they have not already done so themselves, the decrease of the helmet advisable, since only then immediately onto a possibly changing state of consciousness or other complications ( respiratory distress, vomiting, etc. ) can react.

The widespread assumption that first responders can not remove the helmet at an unconscious motorcyclist or should is wrong.