Hoover Pyro-Guard Pyro-Guard is pressure-impregnated, interior fire-retardant treated lumber and plywood for enclosed structural applications. Uses Pyro-Guard is recommended for enclosed structural applications such as: Plywood roof sheathing Roof trusses Rafters Floor joists Mezzanines Shelving Load-bearing walls Floor sheathing Partition walls Studs Interior beams Blocking Steps Stairways Platforms Stages Plywood…