Industrial vacuum cleaners are designed with two basic functions in mind the removal of debris of all types from the floor and the removal of debris of all types from the air in the working environment. The first application was tricky, to say the least, but the specific needs were dealt with until systems and units were produced that could handle almost any type of debris from the floor of a manufacturing company.
At first, the size of the debris was a question to be dealt with. Then there were wet and dry items that needed to be dealt with simultaneously. Extremely hot or corrosive elements were added to the mix and then radioactive debris had to be taken into account. All of this debris, a bi-product of some sort of manufacturing or large-scale commercial operation, had to be dealt with by vacuum cleaner manufacturers. Often, the special requirements of a company were dealt with on a case-by-case basis at the same time as the new plant was being constructed.
Similarly, airborne debris, dust and microscopic particles of whatever was being produced in the shop had to be removed from the air, either to protect the workers or to gather and store the valuable materials to keep from losing them. Huge vacuum cleaners were mounted on rooftops, and behind the factories themselves, that resembled air-conditioning units more closely than vacuum cleaners. But they performed precisely the opposite function. Where air-conditioners cool and then pump air into the factory to keep temperatures comfortable and controlled, these huge vacuum cleaners are sucking the air out of the factories, either from the ceiling levels or from beneath the floor, filtering out the debris and keeping it accessible during cleaning.
Factories that produce fine particulate debris as part of their manufacturing process need to maintain a safe breathing environment for their workers and those companies that are refining a valuable metal need to collect the particulates for later re-use. Both functions are amply served by todays industrial vacuum cleaners.