Health and safety has been a priority for the oil and gas industry for many years. However, occupational hygiene exposures are often not properly assessed to determine the true risk to workers.

This document describes some of the occupational disease hazards (and other hazards) that workers in the oil and gas industry should be aware of. This industry produces and uses many chemical products on its worksites.

Workers exposed to chemicals produced and used in the oil and gas industry may develop occupational diseases of the lungs, skin, and other organs, depending on the amount and length of time of exposures. Workers exposed to hazardous noise levels may develop noise-induced hearing loss. Other dangers include confined spaces, in which untrained workers have been seriously injured or killed.

Exposure control plan (ECP)

Oil and gas industry employers must develop and implement a written exposure control plan (ECP) whenever workers may be overexposed to chemical hazards, including hydrogen sulfide (H2S), drilling fluids, silica, diesel exhaust, and mercury.

An effective plan provides a detailed approach for protecting workers against chemical exposures, including health hazard information, engineering controls, safe work procedures, worker training, and record keeping.

ECPs must include the following elements:

Diesel exhaust

Diesel engines provide power to many types of vehicles, heavy equipment, diesel generators, and other machinery used in the oil and gas industry.

The exhaust from these engines contains a mixture of gases (including carbon monoxide and oxides of nitrogen) and small particles that can affect worker health. Some of these particles have cancer-causing chemicals, known as aromatic hydrocarbons, attached to their surfaces.

Short-term exposure to diesel exhaust can cause eye and upper respiratory (nose and throat) irritation. Long-term health issues can include respiratory disease, cardiovascular problems, and lung cancer.

Engineering controls are the best strategy for controlling worker exposure to diesel exhaust. Possible controls include the following:

Naturally occurring radioactive materials (NORM)

Naturally occurring radioactive materials (NORM) are radioactive elements that have always been present in the earth’s crust and are found naturally in the environment. These include uranium, thorium, radium, and radon. The background concentration of NORM is typically low; however, higher levels may arise as the result of human activities.

In the oil and gas industry, NORM may be present in the liquids and gases from some geological formations. Scale from oil recovery brine, for example, may contain radium at much higher concentrations than the original water source. Sludge and drilling fluids may also contain elevated levels of NORM. Special precautions are needed for handling, transporting, and disposing of these materials.

Workers can be exposed to NORM through exposure to an external source (irradiation) or when radioactive material is taken into the body (for example, through inhalation, ingestion, or absorption). Health effects of exposure depend on the intensity of the radiation, the duration of the exposure, and the organs affected. Longterm exposure to NORM above exposure limits has been associated with certain forms of cancer.

NORM exposures are generally quite low; however, all radiation exposures must be kept as low as reasonably achievable (ALARA).

NORM can be found in many components of operating oil and gas facilities, including:

In order to protect workers who clean and maintain equipment that is potentially contaminated by NORM, or who may enter contaminated tanks or vessels, a written NORM management program should be developed and implemented.

Confined spaces

A confined space is an enclosed or partially enclosed area that is big enough for a worker to enter. It is not designed for someone to work in regularly, but workers may need to enter the confined space for tasks such as inspection, cleaning, maintenance, and repair. A small opening, a high opening, or a layout with obstructions can make entry and exit difficult and can complicate rescue procedures.

Entry into confined spaces can be very hazardous. Workers must not be allowed to enter such spaces unless proper training, equipment, and procedures are in place. Workers have died because they did not know they were entering a confined space with a hazardous atmosphere, and therefore did not take the necessary precautions.

Confined spaces are common in the oil and gas industry, particularly in processing operations. Confined spaces include:

A hazard assessment must be conducted for every confined space on a worksite. Before workers can enter a confined space, the employer must prepare and implement a confined space program that includes written safe work procedures for entry into and work in each of the confined spaces.

Hazardous noise

Noise-induced hearing loss is permanent hearing loss caused by long-term exposure to hazardous noise. The severity of the hearing loss is affected by the intensity of the noise and the duration of exposure.

Sources of hazardous noise are common on oil and gas sites and include the following:

Oil and gas industry employers must develop and implement a written noise control and hearing conservation program where workers are exposed to hazardous noise. The program must include the following elements:

Engineering controls, such as the addition of sound-attenuating curtains or walls, are the best strategy for reducing worker exposure to hazardous noise. Often, however, controls are not enough to eliminate the hazard, so appropriate hearing protection devices must be worn at all times around hazardous noise sources.

Because noise-induced hearing loss develops slowly over time, annual hearing test results are the best way to determine the success of hearing conservation efforts. It is important to review test results and to educate and train workers about the risk of exposure to hazardous noise.


WorkSafeBC (2010). Hydrogen sulfide in industry.

Enform. Exposure control plan (ECP) template for oil-based drilling fluids.

OSHA-NIOSH (2012). Hazard alert: Worker Exposure to Silica during Hydraulic Fracturing. hazard_alert.pdf

OHSA-MSHA (2013). Hazard alert: Diesel Exhaust Diesel Particulate Matter.

IAEA (2003). Radiation Protection and the Management of Radioactive Waste in the Oil and Gas Industry.

WorkSafeBC (2007). Confined Space Entry Program: A Reference Manual.

WorkSafeBC (2006). Sound Advice: A guide to hearing loss prevention programs.

More Information:

WorkSafeBC has a wide range of health and safety information. For assistance and information on workplace health and safety, call toll-free within BC 1-888-621-SAFE (7233) or visit our web site at

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