Safety on the job site is one of the biggest concerns for employers in the Oil and Gas Industry. Workers are regularly exposed to hazardous chemicals in the field, and it’s important that they are aware of all the potential risks so that they can safely perform their job. 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.
Hydrogen Sulfide (H2S)
Hydrogen Sulfide (H2S) is a flammable, colorless gas that is toxic at extremely low concentrations. The principal source of H2S is as a by by-product in the purification of natural gas and refinement of crude oil. It is heavier than air, and may accumulate in low-lying areas. Workers compare the smell to “rotten eggs” and exposure to the gas causes you to quickly lose your sense of smell. Many areas where the gas is found have been identified, but pockets of the gas can occur anywhere. The Occupational and Safety Health Administration (OSHA) created a template for employers to control worker exposure to H2S, properly educate workers on potential hazards, and then provide workers with the correct Personal Protective Equipment (PPE):
- Use exhaust and ventilation systems to reduce hydrogen sulfide levels. Make sure that the system is:
- Separate from other exhaust ventilation systems
- Establish proper rescue procedures to safely rescue someone from a hydrogen sulfide exposure.
- First responders must be trained and properly protected before entering areas with elevated levels of hydrogen sulfide.
- Rescuer protection should include:
- Positive-pressure, self-contained breathing apparatus (SCBA).
- A safety line to allow for rapid exit if conditions become dangerous.
- Use respiratory and other personal protective equipment. If engineering and administrative controls cannot reduce hydrogen sulfide below OSHA’s permissible exposure limit, employers must provide respiratory protection and other PPE, such as eye protection and possibly fire-resistant clothing. Employers must complete a PPE hazard assessment and equipment selection process in accordance with the OSHA regulations before beginning any work activities. Respiratory protection should be at least:
- For exposures below 100 ppm, use an air-purifying respirator with specialized canisters/cartridges for hydrogen sulfide. A full face respirator will provide eye protection.
- For exposures at or above 100 ppm, use a full face pressure demand self-contained breathing apparatus (SCBA) with a minimum service life of thirty minutes or a combination full face pressure demand supplied-air respirator with an auxiliary self-contained air supply. Exposures at or above 100 ppm are considered immediately dangerous to life and health.
Silicosis is a disease that dates back to the ancient greeks It’s an incurable but entirely preventable disease caused by breathing in particles of sand, or respirable crystalline silica. The particles can be invisible to the eye, but the perfect size to slice into the lung’s tightest corners. Workers who breathe in too much silica have the potential to develop lung cancer. The U.S. government has warned about the dangers of breathing silica dust since1938. The Occupational Safety and Health Administration set the current standard for workplace exposure – a 1971 OSHA regulation sets the amount of silica that can be inhaled in a day to about twice the amount that can fit on FDR’s nose on a dime.
Silica is the basic component of sand and rock. Some common silica-containing materials include:
- Concrete, concrete block, cement, and mortar
- Granite, sand, fill dirt, and topsoil
- Asphalt (containing rock or stone)
- Abrasive used for blasting
- Hydraulic fracturing sand (contains up to 99% silica)
Workers performing the following activities are at risk of breathing silica dust:
- Abrasive blasting using silica-containing products
- Cementing operations
- Drilling using dry product additives that contain quartz
- Maintenance of shale dryers (dry particulate may contain quartz)
- Hydraulic fracturing (loading, unloading, moving, or storing sand)
- Sweeping or moving sand or gravel containing silica
Because of the low occupational exposure limit for airborne silica dust, an Engineering Change Proposal (ECP) would likely include an appropriate respirator for all work activities that involve silica.
Mercury is a natural component of oil and gas, and may be present at high concentrations in some formations.When these gas reservoirs are produced and the processed fluids are cooled, liquid mercury can condense within heat exchangers, separators, coolers, valves, and piping. When this equipment (particularly components made from magnesium or aluminum alloys) is taken apart for maintenance or repair, workers can be exposed to mercury vapour.
Work activities that may carry a risk of exposure to mercury in gas processing facilities include:
- Vessel cleaning
- Welding, grinding, buffing, and polishing
- Installation and removal of components or infrastructure
- Hydro excavating
- Electrical work
Chronic (long-term) exposure to high concentrations of mercury vapour affects the central nervous system and can cause stupor, tremors, nervousness, personality changes, and vision and hearing problems. Contact with mercury can also affect the kidneys and cause irritation and burns to the skin and eyes.
Owners must conduct a hazardous materials survey and a risk assessment for mercury at their facilities. This information must be kept on site and communicated to all contractors who will be performing work at these locations. Employers must also develop and implement an effective written ECP for mercury.
Naturally occurring radioactive materials (NORM)
Workers in the Oil and Gas industry can sometimes be exposed to naturally occurring radioactive materials, which are present in the earth’s crust and are found naturally in the environment. These include uranium, thorium, radium, and radon.
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.
NORM can be found in many components of operating oil and gas facilities, including:
- Piping runs, including down-hole piping
- Well heads
- Production manifolds
- Gas/oil separator flow lines
- Dehydrators and desalinators
- Storage tanks
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.