Basically there are two types of spray booths

1) Dry Back type
2) The Water Wash Type

Your choice depends primarily on the type of paint you will be spraying, type of work piece, cleanness of air and rate of production (quantity of spread/hr.)

Function of spray Booth:

To collect overspray and exhaust clean air.
To provide clean air at the operator's breathing level.
To treat the over spray in such a way that it can later be disposed off outside the building without nuisance or hazard.
To reduce fire risk to a minimum in the spray shop.

Dry Back Booths:

The disposable filter spray booth is an efficient choice, and economical too for low volume spray painting operations

Principal of operation
The heart of this spray booth is the special disposable paper filters/paints stop filters. The paper filter consists of two heavy paper with corrugations of unequal size which are attached at the corrugations. Each sheet has rows of perforations staggered relative too the other, both vertically and horizontally, resulting in a tortuous passage, so that air stream strikes at least four surfaces before it leaves the filter, in doing so, the sticky deposits strike the surfaces and adhere, only the clean air being finally discharged.

Water Wash Spray Booth:

1) Conventional Water Wash Booth
2) No pump water Wash Booth

Conventional water wash booth:

All water wash spray booths have a washing tank which contains water/alkali mixture to break down sticky overspray resins. The broken down resin may be collected in this tank.

Most water wash booths have a vertical water screen to catch overspray and carry it down into the washing tank. This screen depends for its function on a circulating pump, nozzles, pipe work and filters.

Modern paints, however, are highly resistant to alkali attacks and since the overspray particles may have only a short contact with the alkali. Sticky paint enters the pump, pipe work, filters and nozzles. Clogging occurs, diminishing the booths efficiency and eventually it ceases to operate.

Since there is nothing to become clogged, the resin particles are encouraged to re-circulate so that they scrubbed again and again. Eventually the resin is completely broken down. Pigment sinks to the bottom of the washing tank as non-sticky silt which is relatively easy dispose off.