It’s all about ENERGY MANAGEMENT
The differences between body protectors and air jackets is very unclear. As a consumer, it is hard to push beyond the various marketing material on each brand to gain clear and unbiased information on actual performance. So I decided to write this article which I hope will allow people to understand the principals of “energy management” in a horse riding fall incident. I don’t have an engineering, physics or medical background but I have gained great insight from countless interesting conversations on the subject of injury and impact, plus further research. So I thought that I would try to impart some of the knowledge that I have gained about the differences in protective gear and how that relates to the reduction of rider injury. This is intended to be a factual and helpful piece, with no reference to brands or design including my own.
I realise that the subject of air jackets is often contentious. I do not wish to partake in the ongoing debate. However there is far too much confusion in the equestrian sector on the differences and how body protectors and air jackets actually perform. I talk to so many individuals at various horse trials who really do want to understand the differences in the technologies. We all want to be able them to make our own informed buying decision, free of a branding and marketing. it is a safety issue, after all and I believe that the purchaser should be able to access impartial, non endorsed information.
Physics exposes the differences
The purpose of a traditional body protector is to help prevent injury to joints, bones and internal organs in the event of a riding accident when thrown from a horse or kicked. It does this by absorbing and spreading the forces involved.
Newton’s third law of motion states: “Every action has an equal and opposite reaction” i.e. push a ball and it rolls away, the more energy put into the push the further the ball goes. The other thing to remember is that energy can’t be destroyed only changed. Therefore when falling from something there is the energy from gravity accelerating the person’s weight (mass) plus the energy given by the thing they fell off (bike, horse etc). This energy has to go somewhere when landing – some of it will go into the ground but the remaining energy goes into the rider’s body. Therefore the choice of safety garment must be shock absorbing so that the body inside is protected.
All body protectors carrying the EN: 13158 or BETA marked labels have been tested to one of 3 levels and this denotes that at each level the body protector is capable of absorbing and spreading a given amount of impact. Protectors meeting BETA Level 3 should provide a level of protection that is considered appropriate for normal horse riding, competitions and for working with horses. These certified body protectors also have specific dimensional and space requirements so that sufficient torso areas are protected. I should point out however, that the safety standard only gives a “pass” or “fail”. It does not reveal “excellence”.
An air jacket is designed to help provide protection by decelerating or slowing down the impact. This is the key difference because it cannot absorb shock. Which is why BETA, the FEI and BE insist that if you are wearing an air jacket it must be worn with a BP to give the correct impact protection. Air jackets offer a partial solution to some types of fall. Its back protection bags reduce impact, but it will not disperse the energy of a fall.
The “threats” in horse riding
In a horse riding environment impact types would be:
- Flat impact ion ground with no hard lumps
- Blunt but point loaded impact i.e. a rock, tree root, fence post or rail
- Sharp penetrative
I would say that the first two and a combination of both were most likely. If when falling from a horse we hit for example a tree root or fence, the energy is transferred into a small area causing greater damage than if we fall onto flat ground.
To a large extent body protectors are designed to emulate a ridged shell with spinal conformity. It shoudl have the effect of wrapping around the rib cage. They should be impervious and ideally largely unbending around the circumference of the upper body, backed up by an impact absorbing and dispersing layer to cushion the blow. Too much flexion in the shell would allow blunt point impact to bend and possibly break a bone.
Air Jackets are not body protectors. Whatever the benefits of wearing these items, currently not of them meet the relevant European CR standard for body protectors for equestrian use. To pass the standard, protectors must be independently tested by a European approved laboratory. One section of the tests uses impact performance test methods to simulate impact due to falls and kicks from horses. Most riders are sitting at over 1.4 metres (4’8″) above the ground. That is a long way to fall, even when the horse is stationary. Once on the ground there is the added danger of being kicked or trampled. An average horse weighs 1000 – 1200 Lbs (455 – 545 KG) so the risk to the rider is significant.
New technologies should be welcome
Back in the 1980’s opponents of the proposed seatbelt law argued that these safety devices would be restrictive and uncomfortable. The statistics show that since their introduction deaths and serious injuries among drivers and passengers have been massively reduced. The same arguments are often heard from riders who, quite naturally, are cautious about spending money on additional riding kit. Properly designed and developed modern protectors are neither uncomfortable nor restrictive. However, it is important to find the correct size, assess the differences and to allow time to become accustomed to the sensation of wearing one.
The BHS have recently launched an accident reporting website and the data collection is revealing some thought provoking evidence.
Finally we are often asked if an air jacket can be worn with a KAN body protector. I do not know of any reason why an air jacket should not be combined with a “moulded” body protector there has not been any testing carried out to establish incompatibility. BETA has issued a statement to support this.
The KAN utilises a motorbike armour that has been developed by Knox. It is a polyurethane foam and performs very differently to the traditional PVC Nitrile found in other body protectors.
Many thanks for reading this, I do feel compelled to share this information as I find that there is apathy about the differences in body protectors and it is tragic to see how a lack of awareness can lead to misconception and sadly the consequences are ever present.