I have been asked to audit our compliance with OSHA space requirements for electrical installations. We have some fairly new machinery that has its plc and motor drives located in the center of the machine. It pulls yarn through a retractable comb which is integrated into the top this panel. You have to crawl under running yarn moving at high speed through this comb in order to check the drives and plc below. Behind is a wheel or pulley that is turning also at high speed without a guard and less than three feet from the panel. It seems illegal to me so can someone tell me if there is an exception that covers this?
Space About Machinery Panels
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Machine safety and guarding
Machine safety and guarding
The OSHA standards at 1910.212(a)(1) requires your employer to provide at least one, or more than one, if necessary, types of guarding for any type of machine hazard. The standard gives some examples, such as point of operation, ingoing nip points, rotating parts, flying chips, etc. In addition, 1910.212(a)(3) requires more specific guarding on the point of operation of a machine; this may be the area where the yarn passes through the comb.
All pulleys less than 7 feet from the ground must be guarded using one or more of the specificed methods in 1910.219(m). If there is a belt involved with the pulley, it must be fully enclosed if it has both runs less than 42 inches above the floor. If the wheel is a flywheel, the requirements in 1910.219(b) would apply. So no ducking down under things or reaching over moving wheels or product lines.
Also, an employer can ensure that their employees are not exposed to any types of moving parts or product by appropriate use of their lockout/tagout program and procedures. Anyway, at all times, the employer is responsible for the safety of their employees.
Machine safety and guarding
The OSHA standards at 1910.212(a)(1) requires your employer to provide at least one, or more than one, if necessary, types of guarding for any type of machine hazard. The standard gives some examples, such as point of operation, ingoing nip points, rotating parts, flying chips, etc. In addition, 1910.212(a)(3) requires more specific guarding on the point of operation of a machine; this may be the area where the yarn passes through the comb.
All pulleys less than 7 feet from the ground must be guarded using one or more of the specificed methods in 1910.219(m). If there is a belt involved with the pulley, it must be fully enclosed if it has both runs less than 42 inches above the floor. If the wheel is a flywheel, the requirements in 1910.219(b) would apply. So no ducking down under things or reaching over moving wheels or product lines.
Also, an employer can ensure that their employees are not exposed to any types of moving parts or product by appropriate use of their lockout/tagout program and procedures. Anyway, at all times, the employer is responsible for the safety of their employees.
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CheeseSarge
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Hi, I just went through NFPA 79 Electrical Standard for Industrial Machinery (2007) version and I found no exception that would allow a panel with limited access as you describe. In fact "11.5 Spaces Around Control Cabinets and Compartments. Access and working space for control cabinets and compartments operating at 600 volts, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized shall comply with the provisions of Chapter 11. Sufficient access and working space shall be provided and maintained around all control cabinets and compartments to permit ready and safe operation and maintenance of such control cabinets and compartments"
Does this physical layout provide the required working distance clearance for the voltages that are inside the enclosure (36 or 42 inches)?
I don't think that crawling under a moving web (yarn) is considered sufficient access. I would believe that this is a foreign made machine and when it was purchased there was no provision in the purchase agreement that it was to comply with NFPA 79. As an OEM of industrial machines in a former life making sure that control cabinets had safe access with proper operating clearances outside of guarded areas was a requirement that was followed to the letter. Keeping our end customers happy made for good repeat business. This was all the more important when foreign made compitetion came into the market that seemed to ignore this factor.
As safetyva states the use of a Lockout/Tagout system should be employed and some fixed guards should be installed at a minimum.
Does this physical layout provide the required working distance clearance for the voltages that are inside the enclosure (36 or 42 inches)?
I don't think that crawling under a moving web (yarn) is considered sufficient access. I would believe that this is a foreign made machine and when it was purchased there was no provision in the purchase agreement that it was to comply with NFPA 79. As an OEM of industrial machines in a former life making sure that control cabinets had safe access with proper operating clearances outside of guarded areas was a requirement that was followed to the letter. Keeping our end customers happy made for good repeat business. This was all the more important when foreign made compitetion came into the market that seemed to ignore this factor.
As safetyva states the use of a Lockout/Tagout system should be employed and some fixed guards should be installed at a minimum.
Thanks, but I'm mainly concerned with OSHA's space about electrical installations. Normally this requires at the voltage used, 3 feet in front of the panel and 6.5 feet in height for headroom. Plus 6 feet above the installation or the ceiling whichever comes first. It would seem to me the pulley would violate the 3.5 feet and the comb and yarn overhead would violate the headroom requirement. Since this is fairly new equipment I'm wondering if there is an exception when it comes to installations built or incorporated into the machine? My electricians must have access to this panel while the machine is running to debug it.
Thanks for your reply. I?m sorry to say it was made in America. The required space is 3 feet according to OSHA for this voltage and the pulley or wheel violates this. The yarn and the comb violate the required headroom. The same standards apply to a manufactured machine as an other electrical installation?
I had some of these problems when i work for a japanese firm. The were importing machinery from japan that did not meet US standards...I had several rounds with the plant manager. I almost got fired over the deal but in the end they gave us the time to make the machinery compliant with US standards.
What you are describing is a machine guarding issue and an electrical issue.
Machine Guarding: OSHA requires physical isolation from hazards as described by safetyva in his post. There are no exceptions for electrical installations or manufactured machines.
Electrical: Once you have installed machine guarding then you can reference NEC 110.26 for working clearances around the electrical panel.
The machine as described is blatantly in violation.
Seems to me you'd better address both the guarding and the electrical simultaneously.
If there is not electrical working space around the cabinet without guards, there isn't going to be working space around the cabinet after guards either.
If you install the guards, then move on to the electrical space requirements, how are you going to get the space required?
The machine sounds like a botch that is only missing two things. a padlock and LOTO tag.
cadpoint
Senior Member
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Hers's something you might get management involved with:
.... "employers can find out about potential hazards at their worksites, improve their occupational safety and health management systems, and even qualify for a one-year exemption from routine OSHA inspections."
http://www.osha.gov/dcsp/smallbusiness/consult.html
I was just think'n that it was an available space that was utilized at the orginal install! I was searching OSHA for some else.
.... "employers can find out about potential hazards at their worksites, improve their occupational safety and health management systems, and even qualify for a one-year exemption from routine OSHA inspections."
http://www.osha.gov/dcsp/smallbusiness/consult.html
I was just think'n that it was an available space that was utilized at the orginal install! I was searching OSHA for some else.
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I would agree but have you ever tried to put a millwright down the same hole with an electrician? Some things just make ya shiver. :grin:
petersonra
Senior Member
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- Northern illinois
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- engineer
If I were the machine maker my argument might be that the panel is in compliance because it is not
Virtually all the debugging might well be accomplished from a computer terminal located elsewhere. if there is an alternative to crawling under the machine to do whatever it is your guys are doing, then it is not required that they access it directly.
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Virtually all the debugging might well be accomplished from a computer terminal located elsewhere. if there is an alternative to crawling under the machine to do whatever it is your guys are doing, then it is not required that they access it directly.
Our company would require the machine maker to fix this machine so that the panel could be serviced. If we caught it before we cut the check then we would not pay until it was fixed. If we caught it afterward and the machine maker would not fix it then we would blacklist the machine maker; we would also internally correct the machine at our expense if the machine maker would not correct it. Safety would red tag this machine and not release it until it was done.
Exposure to hazards in order to reach a panel due to poor design is not acceptable at our site.
petersonra
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- Northern illinois
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- engineer
What hazard is there if you only go to the enclosure when the machine is tagged out?
I agree it is not an ideal situation, but it might not be as bad as some people think it is.
And inconvenient is not unsafe.
How did you plan LOTO when the panel is under the machine?
How do you know you won't have to check voltages in the panel under power?
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
Is that required? Is there an alternate means available to do whatever has to be done without crawling under the machine while the thing is running?
I am not arguing that the design is a good idea.
This kind of thing seems to happen a lot when purchasing agents buy the cheapest thing they can, rather than what is expected by those who have to use/maintain it.
I don't like machines that use fences for guarding either. You ever try to debug them? Just about impossible sometimes.
Well, when you are talking about checking voltages in that panel then it's very similar to checking inside that guard fence. First get your SOP that permits service on powered equipment. Review every aspect of the job with your supervisor. Disable the interlocks on the fence/crawlway so that they inhibit machine motion. Troubleshoot the machine. Pray the changes to the interlocks did not change the fault condition on the machine.
Are the guards or relocating the OP panel required? No.
But our company will not intentionally buy a machine that requires such gymnastics.
And if our purchasing agent redesigns by ledger we attempt to correct it on the floor.
So when a machine unintentially reaches our floor like this then I get awarded the job of refitting it so it has the necessary interlocks and safeguards to service the panel.
In my view and that of my safety department: Crawling under rotating equipment to service a panel surrounded by rotating equipment belongs in a SciFi Horror film. You know, like Galaxy Quest :grin:
petersonra
Senior Member
- Location
- Northern illinois
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- engineer
A lot of times people on one end of the company do not know, or even care what someone on the other end of the company thinks. To say "the company will not..." is pretty meaningless unless everyone in the company is on board, and often that is not the case.
It is certainly something to be avoided if at all possible, and usually it is possible. It often ends up being about money.
One would think that getting a manufacturer to build a panel that is a whole lot easier to get at and service would not be that hard, but a lot of buyers will not pay the extra cost. Having been on the redesign side of trying to relocate machinery panels so they are easier to get at, I can tell you with some confidence that the costs quickly can get out of hand. Its not just the redoing of stuff. Its things people don't even think about that make the cost of redesigns often prohibitive.
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I fully agree. It should be noted though that, at least in my company, I will be going to the vendors and reviewing the machines. If I feel this is the type of machine they produce then I will blacklist them for several years. I have, I will, and it sticks.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
If more people had that kind of blanket authority to spend additional company funds like you do, and the clout to make it stick, these kind of machinery makers would have to change their tunes. But in the real world, very few companies care much about this kind of stuff. they buy the cheapest thing they can, these days even more so.
Your situation is very rare in my experience.
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