Powder coating booths are enclosures dedicated to the powder coating process, generally found in industrial facilities. They’re used primarily for two related purposes: to restrict the dispersal of the powder used in the process, and to contain and capture the overspray — that is, any powder that doesn't adhere to the object. If the powder is dispersed into the facility’s general environment, it can pose a health hazard, especially to anyone who inhales it. In addition, any powder oversprayed can be collected and re-used, an economy not available in wet-painting and difficult to obtain in electroplating.
The process of powder coating operates in one of two ways: in the first, an object is dipped into a bath of coating powder, and in the second, the powder is sprayed onto the object with a special sprayer. An electrostatic charge, imparted either to the object or to the powder itself, provides the adhesion of the powder to the object. Following application, the object is baked in a special oven, during which the powder melts and flows into a hard, smooth surface. In either case, some of the powder can escape into the nearby environment, posing a potential hazard to unprotected workers. Powder coating booths are a more economical solution than providing protective equipment for everyone in a facility and establishing protocols to ensure that they’re actually wearing that equipment.
Powder coating booths generally aren’t sealed off during operation because many applications call for an operator to spray the powder onto the object, although robotics technology has made it feasible to construct and operate powder coating booths that are completely enclosed. The electrical charge that provides for the adhesion of the powder to the object is sometimes imparted to the object by a current passed into it through the clips suspending it in the air; in other cases, the powder itself is charged when it exits the sprayer’s nozzle.
Some powder booths are equipped with a variety of filters to capture oversprayed powder before it can escape the booth; others, especially larger models, employ dust collection technology to ventilate the booth and collect any excess powder from the exhaust. This is an important consideration for facilities that do a great deal of powder coating, because one of the features that makes powder coating an economical alternative to wet painting or electroplating is that very little powder is lost as waste — many powder coating booths promise to collect more than 90% of oversprayed powder, which can then be re-used.