13. Items of plant pumping and spraying concrete or mortar, with or without agitator, whereby the material to be transported is conveyed to the placing position through pipelines, distribution devices or distribution booms. Conveyance is carried out:
for concrete mechanically, by piston or rotor pumps
for mortar mechanically by piston, worm, hose and rotor pumps or pneumatically by compressors with or without air chamber.
These machines may be mounted on trucks, trailers or special vehicles.