Canadian Occupational Safety

36 Canadian Occupational Safety www.cos-mag.com oil transport company. When you run a vacuum pump, the compression of air creates a great deal of heat. The operator must ensure there is continuous fl ow through the vacuum system to keep it cool. "If the fl ow goes static, you can actually create enough heat to cause an explosion. You have to consider that all the time," he says. Operators must also watch and maintain two other systems. One is the emer- gency valves. "You're hauling dangerous goods. All the valves on the truck are self-closing, so if there's an incident where you hit something or there's a rollover, the valves all close by them- selves. You have to maintain that system," Ferriss says. The other system to watch carefully is the positive air shutdown system, required by the gassy atmosphere as well as the diesel engine. "Your atmosphere itself could become the fuel. And if the engine gets a big gulp of this gas, it can run away and explode. So you have to maintain that system. Test it regularly to ensure it works," Ferriss says. Trucks must also have proper TDG (transportation of dangerous goods) placards in place to disclose what they're carrying, Phillips says. "That way, any emergency person- nel who have to respond know by the coding what is on board the truck and what precautions they need to take." Vac trucks should be cleaned off regularly to get rid of oils, mud and paraffi n wax that can impede the proper functioning of parts. The tank interior should be fl ushed out and kept clean of materials that could react with newly added waste liquids. Prior to each job, operators should inspect the tank and pumping equip- ment to ensure they are in good condition. TRAINING AND SAFE PROCEDURES Phillips says workers need fi rst to understand the hazards of operating a vac truck — including toxic vapours, ignition sources and fi res and explo- sions — and be trained in procedures to safely handle the product, includ- ing proper methods of venting vacuum pump exhaust vapours. Operators should be familiar with their trucks and how they operate and know the limitations: what they can pick up and safely handle and what could cause problems, he adds. They should understand proper mainte- nance and inspection procedures as set out by the manufacturer. Knowing how to drive safely with hazardous products and knowing not to drive when fatigued or impaired is impor- tant, too. Workers must be trained in proper evacuation and rescue procedures if there's a toxic gas leak. In case work- ers are exposed to toxic gas, fi rst aid should be available nearby. Before, and sometimes during operations, there should be continu- ous monitoring of air quality at areas where there may be toxic gases or hydrocarbon vapours in the fl amma- ble range, such as the discharge area of the vacuum truck venting hose. It is also important to monitor tank tem- perature gauges (to identify chemical reactions) and tank pressure gauges (to ensure correct pressure in receiv- ing tanks and supply tanks). Tank level indicators should be monitored to avoid overfi lling the tank. One critical safe procedure that operators must follow is the require- ment for proper disclosure, Phillips says. Sometimes, clients do not reveal the nature of the hazardous waste. "There may be acids or other types of hazardous chemicals, and the full scope of the problem with the product doesn't manifest itself until you're transporting it," he says. "We have had situations where operators have picked up a product, it gets agitated in the back of their unit and they fi nd out that their valves, the fi ttings, aren't compatible with the acids. So it eats its way through and starts to spill out as the truck is driving." Operators must be willing, he adds, to say no to a load if they believe they cannot safely handle it or if the client is unwilling to disclose the nature of the product. Supervisors must provide vac truck operators and their assistants (swampers) with the appropriate per- sonal protective equipment (PPE) for the task, which may include hard hats, safety glasses, boots, impact gloves, hearing protection and fall protection. Appropriate PPE will depend on the safety data sheet (SDS) for the prod- uct being carried. When using the hot water washer, workers need to guard against steam by wearing rain suits, rubber gloves, eye and hearing pro- tection, face shields and rubber boots, Ferriss says. Operators and swampers required to enter oil tanks must be equipped with a supplied air unit and a lower explosive limit (LEL) monitor for H2S, he adds. They should also be wearing a harness with a lanyard in case they need to be pulled out. A job site analysis (JSA) is also a valuable tool for identifying hazards related to a specifi c job or work tasks. "(The JSA) says you, as the operator, need to be engaged in what's going on and you need to think. You can't just be told what to do," says Greg Campkin, general manager at Sundre, Alta.,-based Capital Pressure. "A huge portion of the day is spent on making sure everything is looked at before it happens, not dealing with it when it does." Once on site, the vacuum truck operator fi lls in the JSA and checks in with the supervisor, says Ken Elliott, the company's vacuum services super- visor. The operator may be bringing new hazards onto the site, which could affect the people there and the job already underway. The super- visor needs to co-ordinate the vac truck operations and current job, and implement safety controls, if needed. "Shell, Exxon Mobil, all the top oil companies, expect us to have all these JSAs in place, as well as to review them with others on site. So everyone on site has an understanding of what's happening. Then, it's signed off by a supervisor and nobody moves until procedures are in place," says Elliott. Vacuum trucks come under Transport Canada regulations regarding the transportation of dangerous goods, Phillips says. Many specifi cs are set out in CSA B620, B621 and B622. Vac trucks must be inspected and tested on a regular basis. Most trucks must undergo a visual and leak test every six months and be tested annually by a Transport Canada registered facility. Provincial occupational health and safety law on vac truck operation as well as motor vehicle regulations also apply. An investigation into the fl ash fi re incident in B.C. revealed it had been caused by an uncontrolled release of fl ammable vapours near a running truck engine, which became the ignition source. In addition to the failure to control an ignition source, investigators also found other underlying causes: an inadequate hazard assessment done by the facility just before the incident; the defi cient design of the open hopper; and an unknowledgeable facility operator. He was unaware of the degree of the fl ammability hazard of the product in the pup tank. "Vacuum truck operation is an inherently dangerous occupation," Phillips says. "But it can be done safely if you follow appropriate pro- cedures and practices." Linda Johnson is a freelance journalist based in Toronto. She can be reached at lindajohnson@sympatico.ca. oil transport company. When you run a vacuum pump, the compression of air creates a great deal of heat. The operator must ensure there is continuous fl ow through the vacuum system to keep it cool. "If the fl ow goes static, you can actually create enough heat to cause an explosion. You have to consider that all the time," he says. dangerous goods. All the valves on the truck are self-closing, so if there's an incident

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