"I know there are special vacuum cleaners for use in picking up toner in laser printers. What is the problem with using a cheap ordinary vacuum cleaner? Is there a fire hazard? Thanks for any comments."
If you vacuum toner with an ordinary vacuum, a static charge from the toner will build up in the vacuum and shock you. Toner works by static charge. Moving it, as in vacuuming, causes it to give up its charge to the vacuum. Without having a complete ground throughout the entire vacuum can cause charge to build up to quite a high potential. Be safe, use a toner vacuum.
Now if the paper does not get fused, the toner can be rubbed off. This toner, and any spilled toner still retains some charge. As it is moved though an ordinary vacuum, charge is transfered to the various parts of the vacuum. (Much in the same way charge is transfered to a person walking across a carpet in dry weather). When the charge builds up, it has to find a way to ground. In the case of the person walking across the room, the charge is discharged when they touch a metal object such as a light switch cover or door knob. In the case of the vacuum, its the vacuum that builds up the charge. When the person using the vacuum touches the charged portion, the charge is transfered to them (ZAP!!). If the person is holding the part of the vacuum that is getting charged, they get charged as well. Only now they get zapped when they touch something else. A friend of mine worked in a print shop at one time. He spilled a bottle of toner. Instead of getting the toner vacuum used on the copy machines, he used an ordinary shop vac. The metal pipe was attached to a rubber hose. As he vacuumed the toner it was he that got charged. It was when he touched the grounded portion of the vacuum as he was turning it of that he got shocked.
Toner vacuums have all their parts grounded (pipe, hose, canister, motor ect.). These parts are all connected by wires to the ground terminal on the power cord, shunting any built up charge immediately to ground. So it is not the conduction of the toner to the electrical ac line but from the charge the toner itself has.
I don't know about any fire hazard, but I DO know what that stuff will do to an ordinary vacuum cleaner from lessons well learned! Toner/Developer is the finest stuff you may ever see, and will instantly clog all the pores of a regular vacuum bag. You'll go broke just buying bags. And... don't wash any of your clothes/rags with hot water that it has penetrated because it will make the stuff solidify. All my advice is based on repairing copiers over the years.
(From: Ed Wright (firstname.lastname@example.org).)
The point here is that vacuuming toner, which is carbon black and latex, will create a static charge. Using a vacuum that is not intended for this purpose can cause the following. You can blow sensitive components on circuit boards, expecially bias boards on the developer units of the larger copiers and the transfer belt power packs of the smaller machines. Another worrisome possibility is an explosion. I have seen two old toner capable vacuums ignite the toner dust as it went through the vacuum. I admit this is a very rare phenomenon but I would think it would be even more likely in a vacuum not designed for sucking up toner. I would suggest reading on the side of your toner bottle. Most bottles caution about disposing of toner by incineration, the stuff is explosive if the air/fuel mixture is right. It probably wouldn't do much harm but I bet it would play hell with your office.
(From: Le Baron O. Ferguson" (email@example.com).)
Thanks for the response. I think I should state for everyone reading that I am now convinced that there IS a serious fire hazard. One person who responded (by email) has seen two of them "light up."