A fire retardant spray and flame retardant

A fire retardant spray is typically a saturant, meaning that you spray it on wood, fabric, paper or some other absorbent material. The chemical soaks in and bonds with the fibers, making them fire retardant.

One of the most common uses for saturants is to treat fabrics in public spaces, like schools, nursing homes, day care centers, hospitals, restaurants and retail stores. Also included are special events like trade shows, theaters, festivals and concerts. Items typically treated include curtains and drapes, hay bales, trade show banners, plywood dividers, carpets (including carpets on walls), decorations, wall hangings and more.

Fire retardancy for saturants is measured in two key areas, flame spread and smoke development. A Class A retardant for wood, according to ASTM E84 standards, has a flame spread of less than 25, and a smoke developed value of less than 450. For fabric, the standard is NFPA 701, using a simple test to measure flame spread on a 12 inch strip of treated fabric.

There isn't any product out there that is actually 'fire proof,' because anything will burn if it gets hot enough. Flame retardants are designed to substantially slow the spread of flame and give people a chance to react and get out of the building.

The primary job of fire marshals is to ensure that public spaces and events meet the fire codes for their municipality. The most common of these codes are ASTM E84 and NFPA 701, but there are dozens of other codes for specific applications, including steel, drywall and foam insulation, among others.