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16 Canadian Occupational Safety www.cos-mag.com GROUNDING Grounding is connecting one or more conductive objects directly to the earth using ground rods, cold water copper pipes or building steel. Unlike bonding, grounding drains the static charges away. There are three types of grounding: Permanent: This type of grounding would be used for objects that never move, such as a jet fuel tank at an airport. It would have a dedicated grounding fi eld that would have a permanent, welded connection to the tanks. Semi-permanent: This type of grounding is for items that are not moved on a regular basis but do need to move at some point, such as a large drum of material that sits in one spot for weeks or months but needs to be taken away to be refi lled. For this, C-clamps that are connected to the ground source are used which screw in and form a really tight attachment and a very strong bond, says Astl. Portable: Portable grounding is a temporary connection used for items that need to be moved all the time, such as at fi ll stations where fl am- mable liquids are being poured into smaller drums. This is done by using hand-held clamps that are connected to the ground source. Clamps that have sharp points that cut through paint, dirt and rust are important because a bare-metal to bare-metal connection is necessary for proper grounding. MAINTENANCE Oil and gas companies need to ensure their bonding and grounding systems are functioning properly, and that requires some diligence and mainte- nance, says MacGillivray. "You have to understand how the whole system works and that every- thing is operating as it should, parts are connected and grounded to a common ground, for example," he says. "We really emphasize looking at the entire system and entire environ- ment that you're working in." A best practice is to have someone walk around the work sites to ensure the grounding and bonding equipment is in good working order on a regular basis, such as every other month. "Often it's unclear who does that work. Sometimes it falls on the plant electrician because it's static electric- ity, sometimes it falls on an operations person, sometimes it's the safety person; it falls between the gaps and companies need to stand up and say who is in charge of this and let's get a proper system in place," says Astl. It's also important to monitor the level of resistance present in the metal circuits to make sure static electricity can dissipate through the wires and the bonding and grounding equip- ment. The industry standard for resistance is 10 ohms or less. Anything above that and the grounding circuit may be compromised. The resistance can be measured by using an ohm- meter along the whole assembly, or by using a fi xed or portable static ground monitoring system. WORKER CONSIDERATIONS The bodies of workers can accumu- late static charges in excess of 10,000 volts in periods of low humidity, says Hastie. Cotton and cotton blends tend to generate less static electricity than clothing made of wool, silk, synthetic and polyester materials. Cenovus requires its workers to wear natural fi bre clothing under their fi re resistant clothing. And if work- ers get fl ammable material on them, they are trained to douse themselves immediately in water before remov- ing clothing to avoid ignition by static electricity, says Hastie. Cenovus employees receive online training on bonding and grounding. They are responsible for ground- ing themselves in a safe location by touching the building or any ground- ing device at the work site after leaving their vehicle; before commencing work; frequently when working in a hazardous area; and prior to entry of compressor buildings or dehydrators. Workers need to be trained on the right equipment and proper processes for bonding and grounding as well as using spark-resistant hand tools in potentially explosive environments. Enform offers training courses around static electricity awareness, such as detection and control of fl am- mable substances and fi re prevention. "We walk them through the basic concepts, how to identify an issue, how to detect an issue, and how to prevent an event," says MacGillivray. At Cenovus, a pre-job hazard assessment is always required and the supervisor is responsible for identi- fying the potential static electricity sources and the necessary bonding and grounding requirements. Training for supervisor competency is a big focus for Enform right now, according to MacGillivray. "We're trying to make sure safety is part of the work, how you do the work, so not just pointing at a safety offi cer but having a supervisor who is com- petent to monitor that work in fact is taking place the way it should be." While the predominant attitude across the industry toward static elec- tricity is: "I have been doing my job for 10 years and have never had a prob- lem," it only takes one incident for everything to change, says Astl. More education and awareness around the hazards associated with static electric- ity is needed. "You get just the right amount of humidity, just the right amount of splashing and it only needs to happen once and that facility is gone, that person is gone and it's just not worth taking that risk," says Astl. "Static elec- tricity is something you can't smell, you can't sense, can't notice until it's too late." BONDING/ GROUNDING CHECKLIST Identify potential static buildup sources Consider ambient conditions Consider any liquid that has been agitated will produce static charges Ensure tankage and fi lling spouts are bonded together or in metallic contact Check that any ground cable is securely attached from containers to ground rod Ensure ground rod is in good condition Inspect bonding line Ensure grounding systems are in place for portable equipment Check that grounding systems are well maintained Check current continuity 800-873-5725 www.dragonwear.com FR Power Grid 1/4 Zip Dual Hazard Shirt FIRE RESISTANT WORKWEAR LIGHTER TOUGHER Our new fabric is 20% less weight, with HRC2, 15 cal/cm2 protection NFPA 2112 and NFPA 70E certified. Made for SAFETY Built for COMFORT 9016