Types of Preventive Clothing and Their Uses or Applications Part-3

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Chainsaw Safety Clothing:
Chainsaw Safety Mitt or Mittens:
A leather mitt for the operator's left hand that is fitted to (but is free to rotate on) the front bar of the chainsaw. The safety mitt ensures that if kick-back occur the operator's hand remains on the bar of the chainsaw. This means that the kickback is more easily controlled and the chain brake is engaged. The safety mitt also protects the operator's left hand in the same way as chainsaw safety gloves.

Special fabrics have been developed for chainsaw clothing, and this development is still very active. Conventional fabric is useless at protecting against a running chainsaw, being immediately cut through.

There is a real struggle between making a fabric proof against more violent impact, and making it light, flexible and comfortable enough for the user. Clothes which make the user too hot, or which prevent the user moving easily, are a safety problem in themselves. A worker suffering from heat exhaustion is not safe. Extra fabric layers can be added to clothing to improve cut resistance, but clothes which cannot be cut at all by a powerful saw are impractical, even with modern fibres. What is worse, saw and chain technology seems to be outstripping fabric technology. High power saws with aggressively cutting chains are almost impossible to protect against.

A classification scheme has been developed in the European Union to rate trousers, and fabric in general, for protection against cutting.

Table 1: “Chainsaw Fabric Classification”

The chain speed is specified in the manual for a chainsaw. Higher class trousers are more expensive, hotter, and heavier, so there is an advantage to choosing the trousers to match the saw.

There are two standard types of trousers, type A and type C. Type A protects only the front of the legs, and can be supplied as chaps, worn over conventional work clothes, or as conventional trousers. Type C gives protection all round the legs and are almost always worn as ordinary trousers, not over another garment. Chaps are generally used for occasional, farm or homeowner applications. Professional chainsaw operators would choose trousers for comfort and ease of movement, with fallers, ground workers and firewood cutters opting for class A trousers because of the low risk of being cut in the back of the leg. Climbers and tree surgeons would have to wear type C, as they will be cutting from a wider variety of positions. Type C trousers are, of course, highly insulating, and may lead to heat stress if worn for labour-intensive operations such as firewood cutting.

Chainsaw protective fabric works on a number of principles. The outermost layer can be made both tough and slippery, to protect against trivial damage which could compromise the filler material. Beneath this, long, loose fibres of ballistic nylon or Kevlar are laid in layers. When a saw contacts the trousers, the outer layer is immediately cut through but the nylon or Kevlar is drawn out and wraps around the saw's drive sprocket, locking it solid and halting the chain, limiting damage to the operator's leg. Trousers should be slightly baggy, so that there is give and not the chain pulling the leg into the chainsaw, but instead pulling excess stopping fabric into the chain mechanism. After stopping a saw, the trousers are scrapped, and the saw must be field-stripped to remove the fibres and allow it to run again.

If trousers are washed the material inside may degrade over time. As a result trousers should be replaced, and not washed in hot water too frequently. Likewise trousers should be free of rips and tears that may catch on a chain saw or timber when moving through a forest. Chainsaw protective trousers in the EU must comply with EN381-5.

Jacket:
Chainsaw protective jackets in the EU must comply with EN381-11. For detailed information on fabric ratings, see the section above on trousers. The logic is much the same - the protective materials are designed to slow the chain's rate of cutting and clog the mechanism, rather than protect the wearer completely.

Gloves:
Chainsaw gloves have cut-proof fabric protection like that for trousers, but only on the back of the left hand. It's especially important that work gloves are flexible, which limits how much padding they can have. Experience has shown that most chainsaw injuries to the hands occur on the back of the left hand. In the EU, chainsaw gloves must comply with EN381-7.
Figure 22: “Chainsaw gloves. Note that only the back of the left hand glove contains chainsaw protective fabric, and so only that glove carries the chainsaw label.”
Figure 23: “A man cutting while wearing helmet, goggles, ear defenders, gloves, chaps, and boots”
Environment Suit:
An environmental suit is a suit designed specifically for a particular environment, usually one otherwise hostile to humans. An environment suit is typically a one-piece garment, and many types also feature a helmet or other covering for the head. Where the surrounding environment is especially dangerous the suit is completely sealed.

The first environmental suits were diving suits designed to protect a diver from the surrounding water (see timeline of underwater technology). Later developments were designed to protect the wearer from the cold (for example wetsuits and other ambient pressure suits) or from undersea high pressure and the resulting decompression sickness (for example atmospheric diving suits). Protecting the wearer from cold is also a feature of ski suits.
Figure 24: “Red Bull revealing its next generation Environment Suit”
Extreme Environmental Clothing:
Extreme environment clothing normally refers to clothing for Arctic or mountainous areas on land, although it is sometimes used for survival suits worn by mariners. The basic approach is to insulate one's body from heat loss, and keep liquid water or ice out of the insulation.
Figure 25: “Extended Cold Weather Clothing System Developed for US Armed Forces”
Figure 26: “US Marines conducting extreme cold weather training”
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