An explosion that killed two employees at a Florida ammunition and police gear manufacturer prompted federal safety citations and proposed fines of $188,290.

Amtek Less Lethal Systems Inc., which operates as Pacem Defense, was cited for a willful violation for allegedly failing to change its procedures to account for increased inventory of pyrotechnic materials in one section of the factory.

The Occupational Safety and Health Administration also issued six serious citations, which the agency announced March 19. These related to...