Hot work is sometimes necessary for line contractors and electrical workers. This includes operations such as welding, riveting, flame cutting or other fire- or spark-producing activities. Unfortunately, this type of work results in an average of 22 deaths, more than 170 injuries and nearly $500 million in costs each year. As a result, the Occupational Safety and Health Administration and the National Fire Prevention Association have some stringent requirements.
be aware of safety measures
Contractors engaging in hot work should familiarize themselves with the regulatory and consensus rules. These include OSHA’s General Industry Standard CFR 1910.252 Welding, Cutting, and Brazing; OSHA’s Construction Industry Standard CFR 1926.352 Fire Prevention; and NFPA’s 51B, Standard for Fire Prevention during Welding, Cutting, and Other Hot Work. Specific regulations that address marine and shipyard safety also may be applicable.
Hot work can be extremely hazardous. Therefore, prior to conducting any welding, brazing, cutting, grinding, soldering, thawing pipe, torch-applied roofing or chemical welding, OSHA requires a hot work permit. This safety measure ensures all appropriate protocols are met and provides a step-by-step guide for safely completing work. It is also a reminder that contractors have fire prevention responsibilities before, during and after work is done.
According to NFPA, “Hot work has the potential to unite all three parts of the fire triangle: oxygen, fuel, and an ignition source. Oxygen is present in the ambient air. Unsafe practices involving pure oxygen can cause oxygen enrichment (over 22% by volume) in the workplace.
“Fuel includes anything that can be ignited. Examples of common fuels include the following: construction materials such as wood, plastic, insulation and roofing materials, including those in concealed spaces. Flammable and combustible liquids or gases such as fuel, paint, cleaning solvents and simple combustibles include rags, paper, cardboard, lumber and furnishings. Ignition sources can be as simple as the hot work itself.
“Ignition results when any heat source sufficient to ignite a fuel does so. It can occur through the direct or indirect application of heat. Direct application of heat includes welding, cutting and burning. Indirect application includes heat conducted through metal surfaces to fuel sources on the other side and sparks traveling to a distant fuel source.”
Before initiating hot work, workers should inspect the immediate work area to ensure that no flammable or combustible objects are present. If any are found, remove them. Materials such as sawdust on the floor are required to be swept clean within a 35-foot perimeter of the work area. In the event the floor itself is combustible, it can be kept wet or protected with a fire-resistant shield before work begins. When the floor is wet, make sure to protect against electric shock.
As a side note, electric welding equipment must always be grounded before use.
Due to fire risk, it is important to have approved fire-extinguishing equipment on hand in the event one does occur. Cables, hoses and other equipment should be placed away from passageways, ladders and stairways to prevent tripping hazards and keep escape routes clear.
Welding, cutting, grinding and similar activities increase the risk of eye and face injuries. Therefore, it is critical that workers and anyone near the welding areas wear appropriate eye and face protection. Welders must wear the shaded eye and face protection rated for the job they are responsible for.
Additionally, workers should ensure there is adequate ventilation and wear PPE with appropriate fire resistance and have approved respiratory protection equipment as needed. Other precautions and reporting requirements may be necessary when working with certain hazardous materials.
Finally, after completing hot work or leaving the area for any time, workers should power down the equipment they used. For example, when an electrode holder is left unattended, the electrode must be removed and placed in an area where it cannot make electrical contact with people or conducting objects.
When work is finished, mark hot metal to warn others of the possible danger. Turn off and bleed the system when oxyacetylene is not used. Leaking acetylene will create an explosive atmosphere and oxygen can reduce the ignition temperature of clothing and other materials.