Glossary of Fireproofing Terms

F RATING

The time it takes a firestop system to prevent the passage of flame through an opening, as determined by ASTM E-814 (UL 1479).

T RATING

The time it takes for the temperature on the unexposed surface of the firestop system, or any penetrating item, to rise 325 degrees above its initial temperature, as determined by ASTM E-814 (UL 1479).

ASTM E-814

The standard method of fire tests of through-penetration firestops.

UL 1479

The fire test of through-penetration firestops (same as ASTM E-814).

INTUMESCENT

A characteristic of certain firestop products that when exposed to heat, expand to seal and fill any void in the penetration. When exposed to fire, intumescent products form a hard char.

ANNULAR SPACE (ANNULUS)

The distance between a penetrating item and the surrounding opening.

MINERAL FIBER BATT INSULATION

A non-combustible insulation material made from mineral fiber (MINERAL WOOL).

VENTED SYSTEM

A pipe system that is atmospherically vented by design to prevent back flow or vacuum (OPEN).

CLOSED SYSTEM

A pipe system that is completely enclosed, usually carrying fluids under pressure.

PVC PIPE

Common plastic pipe used for cold-water distribution, drain, waste, and vent (POLYVINYL CHLORIDE).

CPVC PIPE

High-grade plastic pipe commonly used for hot-/cold-water distribution, sprinkler pipes, and some chemicals (CHLORINATED POLYVINYL CHLORIDE).

PB PIPE

Plastic pipe with good performance at elevated temperatures, which is used for water and gas (POLYBUTYLENE).

ABS PIPE

Plastic pipe used for water distribution, drain, waste, vent, and sewage (ACRYLONITRILE BUTYLENE).