Portable Generators www.nairanaira.com Generators Generators convert gas or diesel fuel into usable electricity (that is, mechanical energy into electrical energy). If used and maintained properly, gas generators are relatively safe. Portable generators are defined by OSHA as “internal combustion engines used to generate electricity” (OSHA, 2009). http://www.bouncehousesplano.com/generator.jpg and www.peakpowertools.com/Portable-Generators-s/1.htm Generators are commonly used in the construction industry to power tools and machinery when there is little or no access to electricity on the job site. They are useful prior to temporary or permanent power being installed. They are also commonly used during cleanup or recovery efforts after a natural disaster. www.forconstructionpros.com Generators in Construction Electrocution Carbon Monoxide Poisoning Fire and Burns Noise and Vibration Generator Hazards 1. Electrocution Generators can produce a significant amount of electricity, thereby exposing workers to the possibility of being electrocuted. The risk of electrical shock due to improperly-grounded receptacles or their use in wet conditions has led to several accidents and deaths. 2. Carbon Monoxide Poisoning Generators release carbon monoxide (CO) while running and these fumes can accumulate into toxic levels in a matter of minutes. Carbon monoxide is an odorless, colorless and toxic gas. Because it is impossible to see, taste or smell the toxic fumes, CO can kill workers before they become aware of it. http://www.cpsc.gov/cpscpub/pubs/portgen.html Symptoms At lower levels of exposure, CO causes mild effects that are often mistaken for the flu. These symptoms include headaches, dizziness, disorientation, nausea and fatigue. Prolonged exposure to CO will eventually cause brain damage and death. 2. Carbon Monoxide Poisoning According to OSHA, acceptable levels of CO in the air are 50 ppm and lower. Carbon monoxide levels above 50 ppm are deemed hazardous and may become deadly. 2. Carbon Monoxide Poisoning When generators are not used properly, the chances of a fire or burns increases dramatically. Generators run off very combustible liquids that can explode when ignited. Generators also get extremely hot when running and may burn workers. 3. Fire and Burns Generator engines vibrate and create noise. Excessive noise and vibration could cause hearing loss and fatigue that may affect job performance. 4. Noise and Vibration http://actrav.itcilo.org/actrav-english/telearn/osh/noise/nomain.htm Source: Extracted from OSHA Accident Investigation Data 1990-2009 Thirty eight (38) generator fatalities were investigated by OSHA during 1990 thru 2009. Generator Statistics Several accidents and deaths have occurred where generators have been used in confined spaces resulting in the build-up of poisonous levels of carbon monoxide. The Consumer Product Safety Commission reports that numerous CO poisoning deaths have occurred through the use of portable generators. Generator Accidents A worker was working on a jobsite with an electrical generator. He was electrocuted when a 480 volt service was backfed through the generator. Source: Extracted from OSHA Accident Investigation Data 1990-2009 | www.diymedicalnetwork.com Generator Fatality Example Two workers were laying tile in a single family structure. The work was being done in a closed structure, at night, with a gas-powered generator located in the garage. All windows and doors were closed. The bodies of the two men were found the following morning. They died from carbon monoxide poisoning. Source: Extracted from OSHA Accident Investigation Data 1990-2009 | Photo courtesy of: www.galtmile.com/images/wilmagen.jpg Generator Fatality Example OSHA Regulations 1926.404(b)(1)(ii) Receptacles on a two-wire, single-phase portable or vehicle-mounted generator rated not more than 5 kW, where the circuit conductors of the generator are insulated from the generator frame and all other grounded surfaces, need not be protected with ground-fault circuit interrupters. (Otherwise GFCI is required) OSHA Regulations 1926.404(f)(3) (i) Portable generators under the following conditions, the frame of a portable generator need not be grounded and may serve as the grounding electrode for a system supplied by the generator. (A) The generator supplies only equipment mounted on the generator and/or cord- and plug-connected equipment through receptacles mounted on the generator, and (B) The non-current carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame Hard Hat Safety Glasses Gloves Hearing Protection http://www.amtonline.com Best Practices: Personal Protective Equipment Inspect generator prior to use. Operate according to manufacturer’s instructions. Best Practices: Key Safety Procedures Generators should only be used outdoors, never in enclosed spaces. Do not place generators outdoors near doors, eaves, windows, or vents where the exhaust might be drawn indoors. Best Practices: Carbon Monoxide Poisoning Prevention Make sure the generator has 3 to 4 feet of clear space on all sides to ensure adequate ventilation. When using generators in/near enclosed areas, portable CO monitors should be installed in order to detect harmful levels of CO. Proper ventilation and breathing apparatus should be used when CO build up is a threat. Best Practices: Carbon Monoxide Protection If getting dizzy or feeling sick while using a generator, get to fresh air immediately… do not delay! Appliances should be connected to generators using heavy-duty extension cords designed for outdoor use. The cords should be three-pronged. Make sure cords are rated for higher wattages than the total of all appliances connected to the generator. Do not use any damaged or frayed power cords . Best Practices: Shock and Electrocution Prevention Generators should not be used in wet conditions if at all possible. Protect the generator from moisture but be aware of carbon monoxide risks while doing so. Best Practices: Shock and Electrocution Prevention Always dry hands before touching a generator. Do not plug damaged tools into a generator. Always plug electrical appliances directly into the generator using the manufacturer’s supplied cords or extension cords that are grounded. Make sure the generator is properly grounded and the grounding connections are tight. Best Practices: Shock and Electrocution Prevention Some generators come with onboard ground fault circuit interrupters. It is a good practice to use plug-in GFCIs on units that do not have them onboard. Never feed power from a portable generator into a wall outlet. This can create an extremely dangerous situation if the generator backfeeds electricity into the distribution system, possibly resulting in an injury or death to an unsuspecting serviceman working on the powerline. If necessary to connect a generator to house wiring to power appliances, have a qualified electrician install appropriate equipment. Otherwise, the utility company may be able to install an appropriate transfer switch. Best Practices: Shock and Electrocution Prevention http://www.usfa.dhs.gov/citizens/all_citizens/co/generator.shtm Fuel for generators should be stored away from living areas in properly labeled, non-glass safety containers. Generators should be shut down and allowed to cool off before refueling to prevent ignition of fuel or vapors. Best Practices: Fire and Burn Prevention Keep generator fuels away from hot engine parts. Do not smoke around fuel containers. Workers should avoid contact with an operating generator to avoid being burned. Do not use frayed power cords since they may be exposed and cause a fire Best Practices: Fire and Burn Prevention Excessive noise can cause distractions that lead to unsafe work practices Generators should be placed as far from work operations as possible to limit noise pollution If noise cannot be alleviated and is above safe levels, proper hearing protection must be worn Best Practices: Hearing Conservation Tie down generators properly during transportation. Use back feed protection devices to prevent electrocution from a current feeding back into the generator. Upper photo courtesy of : www. ncjournal.wordpress.com Middle photo courtesy of: http://www.gmin.org Lower photo courtesy of: http://www.bunkertours.co.uk/Blankenfelde%20Web/generator.jpg Other Key Safety Procedures Think Safety Work Safely
