What is your opinion on how OSHA feels about extension cords?
1) Our guys will run fans at their machines during the summer. Since we are a job shop, the guys may move to several machines during the day, taking thier fan with them. So the fans are temporary and pprtable.
2) But what about little electric heaters?
3) One man told us that as long as we bought heavy duty exterior extension cords we were okay.
Extension cords should not be used as a replacement or substitute for permanent wiring. We operate under a self-imposed rule of "if an extension cord is in use for more than 30 days, permanent or alternative solutions must be employed". Since what you are powering is portable, you may be ok. Just make sure you inspect the cords for wear on a regular basis. Somebody more knowledgeable than me will probably answer this question much better ;)
I would think since the workers are moving the fans (unplugging and moving to power at another outlet) they are being used in a temporary fashion which is acceptable by OSHA standards. Make sure that when the fans are not in use that they are unplugged from the power source. Of course workers have to make sure that the cords aren't a slip/trip/fall hazard to other workers.
The little heaters, as long as they are the newer ones that will turn off if tipped over and aren't used in area where they are exposed to any flammables, should be fine too.
As far as using the heavy duty exterior extension cords, I would think that would be a good idea as well, again making sure that all are grounded.
As others have said, the use of extension cords must be limited to temporary use only. If OSHA finds an extension cord zip tied or duct taped to a support pole, table etc. it then becomes a permanent installation. Also consider the environment - is the cord going to be used outdoors? Is there oil present? There are cords that are specified (listed) for this use.
Something that came up on an OSHA audit I was involved with recently was the use of shop-made cord sets for temporary power. The entire assembly should be UL listed so it is best to not make your own!