Canadian Occupational Safety

34 Canadian Occupational Safety www.cos-mag.com By Linda Johnson T hree years ago in British Columbia, oil and gas fi eld service workers were unload- ing liquid hazardous waste from a pup tank into an open hopper at a hazardous waste process- ing facility. The pup tank was connected to a vacuum truck. Flammable gas and vapour were released into the atmo- sphere and were able to enter the truck engine's air intake system. Because the truck's engine had been left running, the concentrated airborne gas and vapour ignited and caused a fl ash fi re. One worker suffered serious burn injuries. Vacuum trucks are used extensively in the oil and gas industry to clean up and carry waste material. These prod- ucts, often hydrocarbons, can release hazardous vapours and gases, and the off-gases can cause unconsciousness, serious injury or death. Stringent pro- cedures must be put in place aimed at ensuring trucks are well maintained and operators are not only thoroughly trained but also understand the impor- tance of constant vigilance to changing environmental conditions. Vacuum trucks are tank trucks equipped with a high-powered vacuum pump that sucks up solids, fl uids, sludge or slurry at high speed through a hose. In the oil patch, their central task is to clean up waste — contaminated soil and water, pipeline spills or the resi- due settled out at the bottom of a tank, which may include sand or paraffi n wax — and transport it to a disposal site. Another major use is hydro-vacu- uming (the use of pressurized water to excavate and evacuate soil). In the oil industry, most vacuum trucks, called "combo vacs," are equipped with hot water pressure washers that use steam to clean equipment, wash well heads, wash out tanks and clean up spills. Others also have a scrubber mounted to the truck. The scrubber, a dry granu- lar substance, reacts chemically with hydrogen sulphide (H2S) and "scrubs" the explosive gases out of a product. A RANGE OF HAZARDS Vacuum truck operators in the oil and gas industry face a range of hazards, says Budd Phillips, manager of prevention fi eld services for Fort St. John at WorkSafeBC. One of the biggest risks is exposure to toxic gases. Workers are handling liquids that are toxic and corrosive, and dangerous fumes are released from the liquid waste of oil and gas wells as it is sucked up into the truck. One such gas is H2S, which in low levels can cause eye irritation, nausea and dizziness and in high levels can cause unconsciousness or death. Sometimes a chemical unexpectedly mixes with another to produce a harmful substance; for example, when hydrochloric acid is added to the residue of other products in a tank it can release fumes, which can be lethal. Many of these vapours are also highly fl ammable and can produce fi re or explosions. Com- bustible gases sometimes build up around vacuum operations. In other cases, product loaded in the truck may release fl ammable gases due to agita- tion during transportation. "Then, when you go to dispose of it, you open up the hatch and you pour it out. If it's not a controlled scenario with proper monitoring and the truck shut off, fi res and explosions can occur," Phillips says. "We've seen some catastrophic injuries where workers suffered life-altering burns from explosions when they were oper- ating vac trucks." Moreover, workers who must go inside oil tanks to clean them are essentially entering a confi ned space, which is particularly hazardous because of possible toxic chemical residue. Vacuum truck work often requires people to work with sub- stances under pressure: if a suction line carrying a hazardous product ruptures, any workers standing nearby may be sprayed. Other risks stem from the need to work with hot water, which can leave workers burned or scalded. Vac truck operators also contend with extreme weather conditions and, because work continues around the clock, they often work in the dark with limited lighting. The tanks on the trucks themselves can also be dangerous, Phillips says. The very large, heavy lids can hurt and crush workers. Drilling rig work involves long hours, so operators need to stay attentive to hours of ser- vice and avoid fatigue. Finally, driving presents risks. "One of the highest risks in the oil and gas industry is driving from one workplace to another," he says. MAINTAINING A SAFE TRUCK Vacuum trucks require constant vigilance around maintenance to make sure truck equipment — valves, couplers, vacuum and conductive hoses and tank pressure and temperature gauges — are in proper working order. A particular problem in a vacuum truck is parts overheating, says Marvin Ferriss, manager at Alida, Sask.- based Three Star Trucking, a crude Congratulations to the following OHS professionals who have recently been granted the Canadian Registered Safety Professional (CRSP) ® Professionnel en sécurité agréé du Canada (PSAC) ® designation. The BCRSP is a self-regulating, self-governing organization accredited by the Standards Council of Canada to ISO 17024 (Personnel Certification Body) and by BSI Management Systems to ISO 9001(Quality Management System). Board of Canadian Registered Safety Professionals/Conseil canadien des professionnels en sécurité agréés 6700 Century Avenue, Suite 100, Mississauga, ON L5N 6A4 905-567-7198, 1-888-279-2777, www.bcrsp.ca Alaa Abi Jomaa CRSP Solomon Airebamen CRSP Fethi Amari CRSP Iulia (Julia) Anastasiei CRSP Mario Angelucci CRSP Donald Antonello CRSP Matthew Arnold CRSP Brian Baert CRSP Kamorudeen Bakare CRSP Brittany Baltimore CRSP Jose Javier Barranco Barrera CRSP Nicole Bendig CRSP Michelle Bryan CRSP Caroline Butler CRSP Fawad Butt CRSP Erin Byram CRSP Jacques Champagne CRSP Jayanti Chaudhari CRSP Carl Shing-Ka Cheng CRSP Yee Wa Eva Choy CRSP Adam Cieslak CRSP Karin Clark CRSP Sarah Cleveland CRSP Stephen Coady CRSP Jonathan Collins CRSP Christine Comrie CRSP Michael Cormier CRSP Stephen Crouse CRSP Lorraine Douville CRSP Tricia Drover CRSP Amber Fairhurst CRSP Ahmed Farah CRSP James Feaver CRSP Clare E. Foladore CRSP Leonard Ajonakoh Fotabong CRSP Ryan Freeman CRSP Jennifer Furrow CRSP Janet Gale CRSP Christopher Gemmill CRSP Cristina Ghinet CRSP Jennifer Goertzen CRSP Paul Gray CRSP Francois Guilbault CRSP Kevin Halling CRSP Shellie Hamilton CRSP Claudia Heathfield CRSP Raymond Henderson CRSP William Alexander Henry CRSP Sadiqa Hifsa CRSP Stephen Hippisley CRSP Tamar Hopper CRSP Derek Hyland CRSP Oluwafunmilola Ibikunle CRSP Maria Angelica Idrobo Tellez CRSP Patrick Kearley CRSP Holly Keyes CRSP Dave Kundapur CRSP Victoria Larsen CRSP David Larson CRSP Tyler LeBaron CRSP Su Kyoung Lee CRSP Joshua Litwinowich CRSP Krista Lye CRSP Todd A. MacDonald CRSP Juleen MacEachen CRSP Sean MacInnes CRSP Jill Mackey CRSP Christopher MacLennan CRSP Timothy John MacRae CRSP Daphne McCarron CRSP Michael Richard McCartney CRSP Gaetan Mercier CRSP Shaun Miles CRSP Shabnam Mir Seraji CRSP Mohamed Mohamoud CRSP Lauren Nickerson CRSP Adam Nicolson CRSP Eoin O'Grady CRSP Katlynn O'Hare CRSP Olajide Habib Olaniran CRSP Matthew Osbourne CRSP Jessica Pach CRSP Jill Palsat CRSP Gary Pardy CRSP Jeff Parker CRSP Cameron Peneff CRSP David Phan CRSP Marek Plawinski CRSP Bradley Reid CRSP Dwayne Rogowski CRSP Tanya Rookes CRSP Keren Ruller CRSP Jonathan Sawchuk CRSP Timothy Seabert CRSP Nicholas Seaton CRSP Edward Secnik CRSP Dominique Slade CRSP Mary Slaney CRSP Bradley Spurrell CRSP Jennifer Stadnychuk CRSP Susan Stark CRSP Jillian Sturwold CRSP Clara Sun CRSP Laura Synyard CRSP Jeffrey Thibeau CRSP Lida Thomson CRSP Steve Thrasher CRSP Ashley Tran CRSP Jacquiline Hazel Uy CRSP David Vaillant CRSP Shannon Vollema CRSP Arlaan J. Warren CRSP David Wells CRSP Jillian Wheatley CRSP Glen Williams CRSP Melissa Williamson CRSP Esther Winder CRSP Troy Winters CRSP Board of Canadian Registered Safety Professionals Vacuum trucks produce toxic, fl ammable gases that can be fatal for oil and gas workers

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