One of the common and well-justified beliefs among users of plasma cutters is that because the benefits of using a plasma cutter include reduced risks of sparks and conflagrations compared to oxyfuel cutters, some of the more onerous safety practices associated with the latter need not be followed.
However, using any cutter that makes use of high-speed, ultra-hot plasma involves a number of risks regardless of its safety advantages compared to other types of cutters. Among the most common dangers are burning of clothes and flammable accessories, hand and arm burns and electrical fires and shocks. As the saying goes, safety is an integral part of efficiency. Hence, we’ve come up with the following plasma cutter safety precautions to help you avoid any untoward incidents while carrying out that excellent cut:
Plasma Cutter Safety Equipment
While there is no strict dress code for working with plasma cutters, it is important to be aware of the flammability of one’s clothing and if the clothing cannot be changed, to be ready to wear additional safety equipment over it. Beyond this basic tenet however, there are a number of precautions that need to be taken to ensure that stray sparks or hot metal don’t damage one’s clothes or in extreme cases, cause the fabric to catch fire:
- Wear tightly woven material: Clothes made of tightly woven and heavy fabrics tend to be more fire-retardant since the fire has to consume more material in order to spread. Wool, heavy denim and leather are some of the prime candidates in this category. Note however that all synthetic/polyester materials, no matter how thick or well-woven they are, must be avoided as these have a high plastic/petroleum component and are especially prone to catching flames.
- Button everything carefully: Loose collars and rims can catch fire easily and then act as conductors for spreading the fire to the rest of the fabric. Hence one of the important plasma cutter safety precautions is to button down all clothing to the greatest possible extent.
- Wear full-sleeve clothing: While protecting the entire arm is not mandatory, most users suggest that the arm be covered by a tight fabric that ends a little before the wrist. If you can’t find shirts fitting this criteria, you can fold the sleeves as long as the folded portion does not protrude too much from the safety gloves.
- Safety gloves: Plasma cutters tend to produce stray sparks once in a while and these can easily move backwards and cause burns on your hand, wrist or arm. Further, the handle of the torch might on occasion become excessively hot and thus retard effective cutting. To protect yourself against both these risks, you should wear gloves made of special fire-retardant rubber, polymer or leather. Not that unlike baker’s gloves these should fit your fingers snugly but not be too large, else holding the torch would become difficult.
- Eyewear: Observing the metal closely is vital to achieving a clean and precise cut. However, this can expose the eyes to sparks and even pieces of molten metal. It is important to wear high quality protective eye wear/goggles that are especially designed to guard against such high-temperate risks. Further, since plasma cutting generates excessively bright sparks, one needs to fit the safety eye wear with the correct shade filters.
- High-top shoes: High top boots/shoes that do not have large laces are ideal as they keep the legs safe while maintaining a minimal surface area.
- Don’t wear clothing with protruding cuffs: Protruding cuffs may be fashionable, but they present surfaces that can easily catch fire. Avoid wearing trousers or shirts that have designer cuffs along the front.
- Don’t wear pendants/dogtags: Pendants and dogtags can hang from your neck and thus be exposed to the molten metal and sparks coming from the cutter. If for any reason you do need to wear these (if you’re working in the armed forces), make sure they are safely tucked away inside your shirt.
- Wet clothing: Wet clothing may be fire-retardant but can on occasion act as a conductor for electricity. Shorting and poor grounding of the cutter can lead to serious electric shocks because of the high voltage involved.
Keep the Environs Safe
Cutting requires high concentration and no matter how well you know how to use a plasma cutter, chances are that you won’t be able to notice the growth of that stray fire before it is too late. Hence, it is important to keep the area around the cutter, and indeed the entire workroom, free of materials that may allow for the easy spread of fire:
- Keep flammables at a safe distance: If the workroom is small and you do not have any other area to store your flammables (butane/propane tanks, LPG cylinders, paints and primers, etc), ensure that none of them are within a 35ft radius of the cutter.
- Stand on dry rubber mat/wooden board: Protect yourself against shocks by standing on insulating material eg a rubber mat or wooden board. Conversely, ensure that no exposed part of your body is in contact with a metal surface that is directly connected to the cutter.
- Ensure proper grounding: Before starting any cut, run a quick check to ensure that the cutter has been grounded properly. Good standards by which to judge the cutter’s grounding are OSHA and NFPA 70 of the National Electrical Code.
- No open wires near the cutter: Exposed circuits, even when insulated properly, can be damaged easily due to the high temperature sparks flying from the cutter. This may lead to short circuits and fires. If your circuitry is placed on the wall surface, ensure that PVC boards/panels protect them from incoming sparks. Further, as our plasma cutter reviews have shown, a majority of cutters come with 110V/220V interchangeable plug support. Hence, you should choose the power point that is at a safe distance from the cutting table and hence does not stray into the path of the flame.
- Never keep gas hose at cutting level: When using an external source of pressurized gas, it is important to avoid lowering the gas hose to the level of the cutter as this can cause the gas hose to be punctured or burned leading to rapid ejection of gas. This in turn can cause the cutter flame to grow rapidly out of control leading to serious fire damage.
Procedural Safety Precautions
- Avoid cutting galvanized/coated metals: Coated/galvanized metals can give off noxious gases that may sometimes prove to be flammable or noxious. If you do have to cut, cut slowly and keep an exhaust hood with proper gas removal mechanism over the cutting surface. If you wish to follow professional plasma cutter safety precautions to the letter, you should also consider wearing a respirator with proper air supply while carrying out such cuts.
- Be very careful when cutting metal containers: Containers carry a variety of materials during their period of use. Some of these may have been flammable chemicals and traces of these chemicals may have been left on the inner surface. Before initiating any cut, consult a qualified professional regarding the feasibility of cutting the material.
- Never cut closed/pressurized containers: Closed and pressurized containers may contain gases that can erupt onto the flame. If such gases are flammable, this may lead to their ignition. Further, the gases may be noxious and cause poisoning. Even if they are neither, rapid exit from the container can cause an explosion that throws the cutter and its flame in unwanted directions leading to fire hazards.
- Never hold the torch too close to the nozzle: The closer you go to the nozzle the hotter the handle will get. Further, risks of sparks are greatly enhanced. To avoid these risks, hold the handle near the middle and ensure that the gloves are not too close to the cutter.
Not every one of the plasma cutter safety precautions need to be followed at all times. What is more important is tactful application of the correct precautions at the correct time. Since these precautions are often as much a matter of habit as they are of rote learning, you should always start with simple cuts that ingrain the basic precautions into your procedure.
Once these have become second nature, you can move to more complex cuts and their attendant precautions. If this gradual learning curve is followed, we believe that the above precautions will go a long way in ensuring the safety of your life and limbs regardless of the complexity of the cut and the work cycle involved.