When assessing the size of an air compressor to operate air tools and equipment efficiently you should consider two things. The actual compressor output; stated as FAD (Free Air Delivery) and the storage volume of the receiver tank.
It is the storage volume or size of the receiver tank that is the most important factor to consider to ensure that a air compressor will operate your equipment efficiently.
The tables below show the efficient operating time (in seconds) of a tool under continuous use with different sized receivers (in litres).
Air Tools
Spraying Equipment