There have been a few mentions of intumescent coatingsabove, and it would be helpful to elaborate on them. Intumescent coating is a type of paint that will bubble when it is exposed to heat or flames. The bubbles act as a barrier that is relatively flame resistant. The bubbled coating delays the ignition of the spray foaminsulation. Because of this, intumescent coatings have become more common in building and construction.
A rule of thumb puts two thirds of the coating on the substrate and one third in the air. True HVLP guns use 8–20 cfm (13.6–34 m3/h), and an industrial compressor with a minimum of 5 horsepower (3.7 kW) output is required. HVLP spray systems are used in the automotive, decorative, marine, architectural coating, furniture finishing, scenic painting, and cosmetic industries. Spray Coating