HELMETS
A motorcycle helmet is a type of protective headgear used by motorcycle rider. The primary goal of a motorcycle helmet is motorcycle safety – to protect the rider’s head during impact, thus preventing or reducing head injury or saving the rider’s life. Some helmets provide additional conveniences such as ventilation, face shields, ear protection, intercom etc.
Motorcycle helmets greatly reduce injuries and fatalities in motorcycle accidents, thus many countries have laws requiring acceptable helmets to be worn by motorcycle riders.
There are five basic types of helmet (full face, Motocross, Flip-up, open face, Half helmet) intended for motorcycling, and others not intended for motorcycling but which are used by some riders. All of these types of helmets are secured by a chin strap, and their protective benefits are greatly reduced, if not eliminated, if the chin strap is not securely fastened so as to maintain a snug fit.
FUNCTIONS OF THE HELMET
The conventional motorcycle helmet SHOULD have two principal protective components: a thin, hard, outer shell typically made from polycarbonate plastic, finger glass, or Kevlar and a soft, thick, inner liner usually made of expanded polystyrene or polypropylene foam. The purpose of the hard outer shell is:
1. To prevent penetration of the helmet by a pointed object that might otherwise puncture the skull, and
2. To provide structure to the inner liner so it does not disintegrate upon abrasive contact with pavement. This is important because the foams used have very little resistance to penetration and abrasion.
The purpose of the foam liner is to crush during an impact, thereby increasing the distance and period of time over which the head stops and reducing its deceleration.
WHY YOU SHOLUD USE IT?
To understand the action of helmet, it is first necessary to understand the mechanism of head injury. The common perception that a helmet’s purpose is to save the rider’s head from splitting open is misleading. Skull fractures are usually not life threatening unless the fracture is depressed and impinges on the brain beneath and bone fractures usually heal over a relatively short period. Brain injuries are much more serious. They frequently result in death, permanent disability or personality change and, unlike bone; neurological tissue has very limited ability to recover after an injury. Therefore, the primary purpose of helmet is to prevent traumatic brain injury while skull and face injuries are a significant secondary concern.
The most common type of head injury in motorcycle accidents is closed head injury, meaning injury in which the skull is not broken as distinct from an open head injury like a bullet wound. Closed head injury results from violet acceleration of the head which causes the brain to move around inside the skull. During an impact to the front of the head, the brain lurches forwards inside the skull, squeezing the tissue near the impact site and stretching the tissue on the opposite side of the head. Then the brain rebound in the opposite direction, stretching the tissue near the impact site and squeezing the tissue on the other side of the head. Blood vessels linking the brain to the inside of the skull may also break during this process, causing dangerous bleeding.
It is important that the liner in a motorcycle helmet is soft and thick so the head decelerates at a gentle rate as it sinks into it. Unfortunately, there is a limit to how thick the helmet can be for the simple reason that the helmet quickly becomes impractical if the liner is more than 12inches (2.25cm) thick. This implies a limit to how soft the liner can be. If the liner is too soft, the head will crush it completely upon impact without coming to a stop. Outside the liner is hard plastic shell and beyond that is whenever the helmet is hitting, which is usually an unyielding surface, like concrete pavement. Consequently, the head cannot move any further, so after crushing the liner it comes suddenly to an abrupt stop, causing high accelerations that injure the brain.
HELMET ISSUES in NIGERIA
Since the enforcement of the helmet law in Nigeria which states that all motorbike (Okada) riders must wear a crash helmet and insist that their passenger [if any] wears one as well at all times, several issues weigh on its successful adoption.
WRONG HELMETS
Nigerians are used to problems and have become masters at improvising in the face of lack or difficulty. It is therefore, not surprising that most of the okada riders have only been pretending to comply with the new enforcement of a law. Calabashes, aluminum buckets, cycling helmets, cycle racing helmets, soldier’s helmets, riding hats with metallic stripes painted on them are now used! Commercial motorbike drivers and their passengers have resorted to resorted to all sorts of weird and wonderful headgear since the new law took effect January 1, 2009. Of course, helmets that are not designed for motorcycle riders cannot protect the riders effectively in the event of a crash.
HYGIENE, ‘JUJU’ AND HIGH COSTS
Okada drivers are obliged to carry a helmet for the passenger but many passenger objects to wearing them for hygienic reasons. Some people complain they might have skin diseases;
“If I use a helmet I put a handkerchief under it, “said Seun, a Lagos resident in his 30’s. Others wear a shower cap or even a plastic carrier bag. Many female passengers are seriously concerned about their hairdos. They hold their handbag in one hand and the helmet in the other. In the event of a brush with the police they rest it on top of their braids. A possible issue for both sexes is black magic. Some passengers are afraid of juju (black magic), that they will disappear if they wear the helmet, “said Tayo, 22, who has been an Okada driver for the past year. Okada drivers have been complaining about the cost of proper helmet going sky high, compared to their takings. However hundreds of thousands of motor bikes have been confiscated for non-compliance across the country, and they pay the stipulated fine (about N1, 500.00) and show proof of having acquired a helmet before release of their bikes. In the national orthopaedic hospital in Lagos, where Okada accident victims are bought in every day, staff says the new law was long overdue. Head injuries can result in a hospital stay of between three and six months, and a bill of over N 140,000 out of the reach of many patients.
No comments:
Post a Comment