Canadian Occupational Safety

12 Canadian Occupational Safety www.cos-mag.com A ccording to their calcula- tions, they were too deep to fi nd gas. But, once they had drilled into a gas zone, the operators on a drilling rig near Rocky Mountain House, Alta., had created a gas leak, causing a fi re that took six hours to extinguish. "The gas began rising to the surface from underground. It found a source of ignition on surface from the drill- ing rig, produced a large explosion and then fl ash fi re," says Scott Squires, pre-emergency planning manager at Red Deer, Alta.-based Firemaster Oil- fi eld Services, recalling the 1998 fi re. "Auxiliary equipment and tanks of fl ammable product that were on-site caught fi re in that initial fl ash fi re, and the fi re ball went around the site." Flash fi res pose one of the greatest health and safety risks to workers in the oil and gas industry. A sudden, intense fi re that spreads through the vapours, gas or dust of an ignitable liquid, a fl ash fi re can cause severe burns, while the larger fi res caused by a fl ash fi re often cause death and can last several hours or days. Workers in oil and gas are exposed to the hazard of fl ash fi re during a range of operations, including drilling, completions and well servicing, gas processing, production and SimOps (simultaneous operations). Although the fl ash fi re itself lasts a short duration, it can cause second- or third-degree burns to exposed skin. And due to the 1,500 F to 1,800 F heat, inhalation can damage the lungs and windpipe. The fi re may also produce irritating corrosive or toxic gases. Companies can reduce the risk of fl ash fi res by identifying where fl am- mable vapours are likely to accumulate. The fl ammable liquids that present most hazards are gasoline, raw natural gas (a hydrocarbon consisting mainly of methane) and its byproducts (ethane, pentane, propane, butane) and crude oil. Most hazardous vapours are heavier than air and collect in low or confi ned areas. They are also found in areas where crude oil is processed and near fl ammable liquid storage areas, tanks, pipes and compressors, often due to leaks from fl anges, valves or gaskets. Next, possible ignition sources must be identifi ed. These include static electricity, lightning, welding and any hot surface. Beth Chisholm, group lead, process safety engineering at Calgary-based Cenovus Energy, says preventing fl ash fi res starts with an understanding of the physical properties of materials and chemicals: Are they fl ammable? How could they be dispersed? At what temperature do they produce vapour? At what concentration will a vapour or gas ignite? "Supervisors and workers can manage fi re hazards by preventing the release of fl ammable materials and by being prepared if a release occurs. At Cenovus, we ventilate our buildings to prevent fl ammable materials from accumulating and are able to auto- matically isolate equipment in case of a release," she says. Chisholm says supervisors must also ensure all potential ignition sources are managed. "In accordance with the Canadian Electrical Code, we classify our facili- ties based on the potential for fl ash fi res and use electrically classifi ed equipment that is insulated to prevent ignition in areas with fi re risk. One of the most often overlooked ignition sources is the hot exhaust piping of engines. It can be hot enough to ignite fl ammable vapours." Alan Royer, technical director of operations and maintenance at Edmonton-based Petroskills, says training should cover how to conduct proper isolation procedures so, if there's an incident, workers can reduce the amount of gas released. "You need an understanding of what is in the piping and be able to follow a pipe from, say, a vessel through buildings to where it is going — and know what type of isolation valves are in it, where they're located and how to access them," he says. Personal protective equipment (PPE) is an important control against the hazard of a fl ash fi re. PPE is designed to reduce the severity of burn injuries caused by short-term exposure to fl ash fi res. It must be clean and free of fl ammable products, such as grease and oil. Coveralls, shirts, pants and jackets must be fi re resis- tant and should be made of natural (cotton or wool) material in a plain or twill weave. Fabrics certifi ed by the Canadian General Standards Board, in Gatineau, Que., consist entirely or primarily of Nomex, and sometimes a small amount of Kevlar. Cenovus uses fl ame resistant cloth- ing as basic PPE for all personnel in areas where there is a risk of fl ash fi re. "It's important to keep sleeves rolled down and coveralls done up to achieve the best protection," says Chisholm. "We instruct all workers to wear cotton or wool under their FRC (fl ame resis- tant clothing). Materials like polyester could melt in a fl ash fi re and adhere to the skin, causing injury." Royer says workers can protect their heads and faces by wearing a hard hat and balaclava made of a fi re retardant material, such as Nomex. Safety glasses should be CSA-approved. These have plastic polycarbonate lenses, are light- weight and impact resistant and may have heat resistant frames. Gloves must be fi re resistant and can be made of insulated leather or polymers, such as Kevlar, Nomex and PBI, or a cotton- type material or canvas, Royer says. They should not include any nylon or polyester. Boots should be steel- toed and fl ame resistant (often with Nomex/Kevlar uppers). They may also have rubber outsoles that are resistant to heat and fi re. Royer advises the boots also provide good ankle support to prevent spraining. In the event of a fl ash fi re, employ- ers need an emergency response plan. It must be tailored to the equipment and training levels of employees at its facilities, Squires says. Generally, he says, the main steps in a fl ash fi re emer- gency response plan are: • Evacuate to a safe area. • Notify others. • Activate alarm (to company or local fi re department or industrial fi re- fi ghting company). • Determine if any co-workers need medical care. • Isolate the source of the fi re. It's important that the plan set out each step clearly, Squires adds. In an emergency, people may forget what they were trained to do. "The adrenalin is fl owing at the maximum. So, they need to have a step-by-step procedure to follow." Linda Johnson is a freelance writer based in Toronto. She can be reached at lindajohnson@sympatico.ca. Flash fi res can cause 3rd-degree burns, escalate to larger fi res By Linda Johnson Just a Safety Is No Accident. Ensure your protection with FireZero innovative technology and superior comfort garments. www.tosaveandtoprotect.com O I L A N D G A S

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