Just like the electric, IT DEPENDS.
Gas usage will be determined by the paint booth’s heating power. Heating in the paint booth industry is generally expressed in Btu/hr and is almost always a direct fire application. Indirect gas and oil fired applications still exist in old or used paint booths from the 80’s & 90’s but are generally obsolete in the automotive market. Any new paint booth will come standard with direct fire heat as of about 20 years ago. Read more on direct vs. indirect fire heated paint booths.