What is Hot Work?

What is Hot Work?

Hot work is any work that involves burning, grinding, cutting, brazing, soldering, welding, using fire or spark-producing tools. It can also be described as any work that produces a source of ignition.

In the drilling environment for example, potentially hazardous areas include, but are not limited to, well heads, fuel tanks, mud tanks, tank batteries, gas separators, and confined spaces where gases can accumulate.  

It is important to bear in mind that workers performing hot work are exposed to the risk of fires from ignition of flammable or combustible materials in the space, and from leaks of flammable gas into the space from hot work equipment.  This eventually could result in workers getting burned by fires or explosions during hot work.

It is therefore our suggestion that the following basic precautions be observed during hot works:

Hot work should be performed in a safe location with any possible fire hazards removed.

Screens or guards should be used to confine the heat, sparks and slag.  Hot work should not be performed where flammable vapors or combustible materials exist.

Ensure that suitable fire-extinguishing equipment are immediately available with a fire watch man in charge.  The fire watch man must be available throughout the duration of the job and he must not be given any other assignment. The fire watcher must have fire-extinguishing equipment readily available and be trained in its use. He must be familiar with facilities for sounding an alarm in the case of fire. He must also watch for fires in all exposed areas, try to extinguish them only when obviously within the capacity of the equipment available, or otherwise sound the alarm. He may remain on site at least a half hour after completion of welding or cutting operations to detect and extinguish possible smoldering fires.  

Both the welder and fire watchman must be mindful of getting burned by a flash fire or explosion that could results from an accumulation of flammable gases, such as Methane or Hydrogen Sulfide.

During hot work operation, monitor the atmosphere with a gas detector is very essential. Whenever a flammable or combustible gas exceeds 10 percent of the lower explosive level (LEL), the operation must be stopped, source of the gas identified and the leakage repaired.

Before commencement of hot work, risk assessment must be conducted by a competent person to determine where the hazards exist.

Since injuries associated with hot work (such as welding fumes, UV light, sparks, noise, or skin injury) could be very serious, the following additional precautions must be considered.

Job area must be inspected to ensure all fuel and other sources of ignition are isolated by any or a combination of the following - shielding, screening, clearing the area, lockout/tagout, soaking flammable material with water.

Wearing of appropriate PPE such as face shield, leather welder's vest, and gauntlet gloves and denim clothing are inevitable.

UV shielding for arc welding must be provided where practical and welding and cutting equipment must be inspected before use whether arc or gas welding or burning.

Leak test should be conducted on gas torches, gauges and hoses.

Hot work permit must be reviewed and availability of adequate fire watch/fire protection equipment also.

Adequate ventilation from toxic welding and cutting fumes is paramount including provision of fan where applicable to avoid accumulation of toxic gases within a confined space.

A hazardous atmosphere exists in oxygen-deficient (atmospheric concentration of less than 19.5 percent or oxygen-enriched atmospheric concentration of more than 23.5 percent). These two extremes must be considered especially during confined space (mud tank, water tank, oil tanks, hoppers, sump, pit or cellar) activity.

The use of written permit system to document entry authorization, the work to be performed, and the results of the gas monitoring is essential.  Also, both a hot work and confined entry permit are required for welding, cutting or brazing within a confined space.

Another hazard exists from falling or rolling injuries from improper gas cylinder storage, so employees must ensure cylinders are properly stored in an upright position and chained, different gas type in separate racks.

Again workers must store full and empty cylinders in separate racks, chained, upright and properly.

Gauges and regulators must be removed and protective valve caps installed before transporting to avoid fire or explosion. Cylinders should be stored in a dry, well-ventilated location away from flammable substances.

Hazards associated with grinding including sparks, noise, eye and skin injury from flying metal filings, grinding wheel pieces, having fingers or hands caught in the grinding wheel and being struck by portable grinder among others must be guided against.

Our advice here is the use of appropriate PPE, such as face shield, ear protection, nose mask, cotton or denim clothing etc. as operations demand.

Employers must provide spark arrestors for internal-combustion engines, post "NO SMOKING" signs wherever a flammable gas or vapor hazard exists, locate "spark producing" equipment or facilities well away from potential hazard areas, prohibit vehicles with catalytic converters from the immediate vicinity of work, prohibit open flames from site in addition to aforementioned precautions above.

Finally, it is necessary to provide for safety training programs to cover hot work operations.

This allows employees to pre-empt potential hazards of fire or explosion and expose them to dangers associated with Hot Works, flammable gases or vapors from internal-combustion engine sparks, open flames, smoking, welding operations, electric power tools, two-way radios and all other elements highlighted above.