Abstract: To protect sprinkler system risers and supply pipes from accidental or vandalistic damage, in an extremely simple and economical manner, a fork-shaped element is pounded down in straddling relationship around each riser and the associated pipe joint. The legs of the fork are thus on opposite sides of the riser and joint, whereas the hollow body of the fork element encompasses and restrains the riser. The fork element may be economically manufactured from a single sheet of metal, with a tubular body and diametrically-opposed parallel legs adapted to straddle the joint in the horizontal supply pipe.