What is a firestop?

A firestop is a safety measure designed to prevent the spread of fire, smoke, and toxic gases through openings or penetrations in fire-rated walls, floors, and ceilings. These openings typically occur when pipes, cables, ducts, or other services pass through fire-resistant barriers.

The primary purpose of a firestop is to maintain the fire rating of the assembly (such as a wall or floor) by sealing or blocking the penetration. This helps to contain fire, heat, and smoke within a compartment, allowing occupants to safely evacuate the building and providing additional time for firefighting efforts.

Firestops are typically composed of fire-resistant materials like fire-rated sealants, mortars, and putties, as well as firestop devices such as collars, wraps, pillows, and boards. These materials are installed around the penetration or opening, forming a seal that can withstand the passage of fire for a specified period, usually determined by the fire rating requirement of the building code.

It is essential to install firestops correctly, following the manufacturer's instructions and complying with building code requirements. Firestop systems are tested and evaluated according to recognized standards, such as ASTM E814 or UL 1479, to ensure their effectiveness in resisting the spread of fire and smoke.

Regular inspection, maintenance, and repairs of firestop systems are crucial to ensure their ongoing effectiveness. Changes to the building's services or modifications in the fire-rated barrier should be reviewed and approved by a qualified fire protection professional to maintain the integrity of the firestop system.

In summary, firestops play a vital role in fire safety by preventing the spread of fire and smoke through penetrations in fire-rated barriers. They are designed, installed, and maintained to protect building occupants and minimize property damage during a fire.