Dangerous restart: Difference between revisions
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(DHHS (NIOSH) Publication No. 99–110 July 1999). |
(DHHS (NIOSH) Publication No. 99–110 July 1999). |
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The dangerous restart hazard is currently addressed by OSHA, NFPA and the CSA with mandatory requirements for hazard reduction through the use of industrial grade safety devices. |
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(Electrial Standard for Industrial Machinery 2002 Edition 7.5.3 Restarting) |
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(OSHA 29CFR#1910.213(b)(3)* |
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The mandatory safety devices require installation by licensed electricians. The cost for implementing this safety device including installation averages between $300 and $1,000US depending on electrical requirements of the machinery and local electrician rates. |
The mandatory safety devices require installation by licensed electricians. The cost for implementing this safety device including installation averages between $300 and $1,000US depending on electrical requirements of the machinery and local electrician rates. |
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Due to the cost and size restriction, there are currently no requirements for |
Due to the cost and size restriction, there are currently no requirements for restart hazard reduction on appliances, small tools and hand held power equipment. |
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There are currently an average of 25 power tools and appliances in the average Wood, Metal and Home Economic Shops in Public Middle and Hign Schools across the U.S. that posess dangerous restart hazards. |
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Example #1 |
Example #1 |
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Mother and child are working in kitchen with counter top mixer. The mixer is on with cake frosting in the bowl. Power is cut as a result of a local power outage. The mother turns away to evaluate why the power is out. The mixer power switch is still in the "on" position. The young child reaches into the bowl of the now powerless mixer to sample the frosting. Power is restored. The mixer comes on |
Mother and child are working in kitchen with counter top mixer. The mixer is on with cake frosting in the bowl. Power is cut as a result of a local power outage. The mother turns away to evaluate why the power is out. The mixer power switch is still in the "on" position. The young child reaches into the bowl of the now powerless mixer to sample the frosting. Power is restored. The mixer comes on causing injury the childs right hand. |
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Example #2 |
Example #2 |
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Man is using electric trimmer to cut hedges around exterior of home. Trimmer is plugged into outlet on exterior of home |
Man is using electric trimmer to cut hedges around exterior of home. Trimmer is plugged into outlet on exterior of home 75' from where man is working. The trimmer switch is locked in the "on" position and in normal use. Extending beyond the reach of the trimmer's power cord the plug is accidentally pulled from the outlet on the house 75' away. The man puts down the trimmer, switch still locked in the "on" position and walks with his back away from the trimmer towards the outlet. A 9 year old boy playing nearby sees the trimmer on the ground and approaches it. He picks is up with both hands. Back still turned the man re-inserts the trimmer's power cord plug into the outlet. The trimmer starts immediately, severly injuring the boys fingers on both hands. |
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A 25-year-old male worker at a concrete pipe manufacturing facility died from injuries |
A 25-year-old male worker at a concrete pipe manufacturing facility died from injuries |
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he received while cleaning a ribbon-type concrete mixer. The victim’s daily tasks included cleaning out the concrete mixer at the end of the shift. The clean-out procedure was to shut off the power at the breaker panel (approximately 35 feet from the mixer),push the toggle switch by the mixer to make sure that the power was off, and then enter the mixer to clean it. No one witnessed the event, but investigators concluded that the mixer operator had shut off the main breaker and then made a telephone call instead of following the normal procedure for checking the mixer before any one entered it. The victim did not know that the operator had de-energized the mixer at the breaker. Thinking he was turning the mixer off, he activated the breaker switch and energized the mixer. The victim then entered the mixer and began clean ing with out first pushing the toggle switch to make sure that the equipment was de-energized. The mixer operator returned from making his telephone call and pushed the toggle switch to check that the mixer was de-energized. The mixer started, and the |
he received while cleaning a ribbon-type concrete mixer. The victim’s daily tasks included cleaning out the concrete mixer at the end of the shift. The clean-out procedure was to shut off the power at the breaker panel (approximately 35 feet from the mixer),push the toggle switch by the mixer to make sure that the power was off, and then enter the mixer to clean it. No one witnessed the event, but investigators concluded that the mixer operator had shut off the main breaker and then made a telephone call instead of following the normal procedure for checking the mixer before any one entered it. The victim did not know that the operator had de-energized the mixer at the breaker. Thinking he was turning the mixer off, he activated the breaker switch and energized the mixer. The victim then entered the mixer and began clean ing with out first pushing the toggle switch to make sure that the equipment was de-energized. The mixer operator returned from making his telephone call and pushed the toggle switch to check that the mixer was de-energized. The mixer started, and the operator heard the victim scream. He went immediately to the main breaker panel and shut off the mixer. |
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Example #4 |
Example #4 |
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A couple in New Jersey was closing up their pool cabana for the winter prior to leaving the residence for their winter home in Florida. It was common practice to shut off the circuit breaker for the cabana during the winter. The couple then loaded the pool furniture, including several seat cushions into the cabana. Inside the cabana was an electric cooktop used for entertaining during the summer months. |
A couple in New Jersey was closing up their pool cabana for the winter prior to leaving the residence for their winter home in Florida. It was common practice to shut off the circuit breaker for the cabana during the winter. The couple then loaded the pool furniture, including several seat cushions into the cabana. Inside the cabana was an electric cooktop used for entertaining during the summer months. At some point the burner switch for the cooktop was accidently switched to the "on" position. As a result of the cabana breaker being off, the cooktop did not heat up. The couple left for their Florida home. |
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In early January a water leak was |
In early January a water leak was reported in the main house by the couple's alarm company and a plumbler was summoned to repair the problem. The plumber repaired the leak and prior to leaving, made sure that he turned on all of the circuit breakers in the panel. This included the circuit breaker for the cabana cooktop. |
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Later that evening the fire department was called to extinguish a blaze caused by the cushions located on top of the cooktop in the cabana. By the time the fire deparment had arrived the fire had destroyed both the cabana and the residence. |
Later that evening the fire department was called to extinguish a blaze caused by the cushions located on top of the cooktop in the cabana. By the time the fire deparment had arrived the fire had destroyed both the cabana and the residence. |
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Revision as of 23:08, 8 January 2010
A dangerous restart occurs when power or energy is applied to a device whose "on / off" switch was in the "on" position when power was applied. NIOSH refers to this hazard as "The Uncontrolled Release of Mechanical, Electrical and Other Types of Hazardous Energy" (DHHS (NIOSH) Publication No. 99–110 July 1999).
The dangerous restart hazard is currently addressed by OSHA, NFPA and the CSA with mandatory requirements for hazard reduction through the use of industrial grade safety devices.
(Electrial Standard for Industrial Machinery 2002 Edition 7.5.3 Restarting) (OSHA 29CFR#1910.213(b)(3)*
The mandatory safety devices require installation by licensed electricians. The cost for implementing this safety device including installation averages between $300 and $1,000US depending on electrical requirements of the machinery and local electrician rates.
Due to the cost and size restriction, there are currently no requirements for restart hazard reduction on appliances, small tools and hand held power equipment.
There are currently an average of 25 power tools and appliances in the average Wood, Metal and Home Economic Shops in Public Middle and Hign Schools across the U.S. that posess dangerous restart hazards.
Examples of Dangerous Restarts are as follows:
Example #1 Mother and child are working in kitchen with counter top mixer. The mixer is on with cake frosting in the bowl. Power is cut as a result of a local power outage. The mother turns away to evaluate why the power is out. The mixer power switch is still in the "on" position. The young child reaches into the bowl of the now powerless mixer to sample the frosting. Power is restored. The mixer comes on causing injury the childs right hand.
Example #2 Man is using electric trimmer to cut hedges around exterior of home. Trimmer is plugged into outlet on exterior of home 75' from where man is working. The trimmer switch is locked in the "on" position and in normal use. Extending beyond the reach of the trimmer's power cord the plug is accidentally pulled from the outlet on the house 75' away. The man puts down the trimmer, switch still locked in the "on" position and walks with his back away from the trimmer towards the outlet. A 9 year old boy playing nearby sees the trimmer on the ground and approaches it. He picks is up with both hands. Back still turned the man re-inserts the trimmer's power cord plug into the outlet. The trimmer starts immediately, severly injuring the boys fingers on both hands.
Example #3
A 25-year-old male worker at a concrete pipe manufacturing facility died from injuries he received while cleaning a ribbon-type concrete mixer. The victim’s daily tasks included cleaning out the concrete mixer at the end of the shift. The clean-out procedure was to shut off the power at the breaker panel (approximately 35 feet from the mixer),push the toggle switch by the mixer to make sure that the power was off, and then enter the mixer to clean it. No one witnessed the event, but investigators concluded that the mixer operator had shut off the main breaker and then made a telephone call instead of following the normal procedure for checking the mixer before any one entered it. The victim did not know that the operator had de-energized the mixer at the breaker. Thinking he was turning the mixer off, he activated the breaker switch and energized the mixer. The victim then entered the mixer and began clean ing with out first pushing the toggle switch to make sure that the equipment was de-energized. The mixer operator returned from making his telephone call and pushed the toggle switch to check that the mixer was de-energized. The mixer started, and the operator heard the victim scream. He went immediately to the main breaker panel and shut off the mixer.
Example #4
A couple in New Jersey was closing up their pool cabana for the winter prior to leaving the residence for their winter home in Florida. It was common practice to shut off the circuit breaker for the cabana during the winter. The couple then loaded the pool furniture, including several seat cushions into the cabana. Inside the cabana was an electric cooktop used for entertaining during the summer months. At some point the burner switch for the cooktop was accidently switched to the "on" position. As a result of the cabana breaker being off, the cooktop did not heat up. The couple left for their Florida home. In early January a water leak was reported in the main house by the couple's alarm company and a plumbler was summoned to repair the problem. The plumber repaired the leak and prior to leaving, made sure that he turned on all of the circuit breakers in the panel. This included the circuit breaker for the cabana cooktop. Later that evening the fire department was called to extinguish a blaze caused by the cushions located on top of the cooktop in the cabana. By the time the fire deparment had arrived the fire had destroyed both the cabana and the residence.