Safety in Gas Welding and Cutting:
Protecting Against Fumes, Heat and Noise
By Paul Mercuri
In the first part of this series, we discussed safety precautions when working with gases and regulators. These are not the only potential health hazards in the welding environment. A careful welder also has to consider the effects of fumes, heat rays/sparks and noise on individual health and the working environment.
Fumes and gases produced during welding and cutting can harm your health. Potentially hazardous materials may exist in fluxes, coatings, and filler metals that can be released into the atmosphere during heating. All fumes and gases should be considered as potentially hazardous. The simplest step to safety is to keep your head out of the fumes and back far enough to prevent breathing in the fumes and gases caused by the flame. Do not weld, cut or heat dirty plate or plate contaminated with unknown material. Remove all paint and galvanized coatings before heating. Material Safety Data Sheets also provide helpful safety and health information.
Another important safeguard is the use of proper ventilation to protect the operator from the evolving noxious fumes and gases. The degree and type of ventilation will depend on the specific operation and varies with the size of work area, the number of operators, and the types of materials used. Air samples can be taken to find out what respiratory protection is needed. In some cases, general natural-draft ventilation may be adequate.
Other operations may require forced-draft ventilation, local exhaust hoods, booths, personal filter respirators or air supplied masks. Operations inside tanks, boilers, or other confined spaces require special procedures, such as the use of an air-supplied hood or hose mask. In industrial operations, measurements may be needed to determine whether adequate ventilation is being provided. A qualified person, such as an industrial hygienist, should survey the operations and environment. Follow their recommendations for improving the ventilation of the work area.
Our second concern is injury from infrared radiation from the flame or hot metal, commonly known as “heat rays” and welding spatter. Flames and hot metal emit infrared rays. Operators may receive eye and skin burns after overexposure to infrared rays. Long overexposures may cause severe eye burn. Hot welding spatter can also cause painful skin burns and permanent eye damage. To be sure you are fully protected from the infrared radiation and spatter, follow these precautions:
(1) Wear safety goggles made for gas welding and cutting purposes. These will protect your eyes from radiation burns and from sparks or spatter. Use the correct lens shade to prevent eye injury. As a rule of thumb, start with a shade that is too dark to see the work zone. Then go to a lighter shade that gives sufficient view of the work zone without exerting strain on your eyes. Observers should also use proper protection. Here are some common filter recommendations (adapted from ANSI Safety Standard Z49.1):
Application = Lens Shade No.*
- Brazing = 3 or 4
- Light Cutting (up to 1 in) = 4 or 5
- Heavy Cutting (over 6 in) = 5 or 6
- Light Welding (to 1/8 in) = 4 or 5
- Medium Welding (1/8 to 1/2 in) = 5 or 6
- Heavy Welding (over 1/2 in) = 6 or 8
(2) Protect against eye injury, mechanical injury or other mishaps by wearing safety glasses with side shields when you are in any work area.
(3) Wear clean, fire-resistant, protective clothing. Protect all skin areas from sparks or spatter. Avoid spark and spatter traps by wearing a jacket with no pockets and pants with no cuffs. Sleeves should be rolled down and buttoned. Collars should be buttoned. Wear high, snug-fitting safety shoes and gauntlet gloves. Protect your head by wearing a leather cap or hard hat. Wear ear protection where there is a chance of sparks or spatter entering your ears. Do not wear clothing stained with grease and oil. These may burn if ignited by the flames or sparks and spatter. For high heat work, such as heavy cutting, scarfing or oxygen lance operations, face shields, fire-resistance aprons, leggings or high boots may be needed. Remove all flammable and readily combustible materials, such as matches and cigarette lighters, from your pockets.
(4) Protect neighboring workers and passersby by shielding your station with metal or heat resistant shields.
Finally, noise in the welding environment can damage hearing. It is important to wear ear protective devices or earplugs when heavy cutting, scarfing or oxygen lancing is being performed or in noisy work areas. In addition, proper ear protection can prevent hot spatter from entering the ear. Most of these recommendations seem self-evident but it is unfortunate how frequently these basic safety rules are not followed and injury results. It can only take a moment for a serious injury to occur. Take the time to make safety a priority in the welding environment, for your own sake and the sake of those around you!