The automatic fire sprinkler business is huge, with annual sales of nearly $3.5 billion, with no competition from overseas, reports Metalworking News.

The publication notes that about 16 million sprinkler devices have been installed in North America, with about 15 million of the total in the United States. The devices and systems are not imported.Until recently, automatic sprinklers were primarily installed for commercial and industrial users. Since 1983, however, they have begun to be installed in residences, with the most recent count placing installations at 100,000 living units.

Piping represents about 70 percent of the material used in a sprinkler system, and industry estimates place piping requirements at about 400 million linear feet per year. About 96 percent of the piping is black steel, 3 percent plastic and 1 percent copper.