One critical difference for specifiers is to distinguish between fire retardant and intumescent paint. Retardant paint slows flames from spreading and are meant for fires to self-extinguish. Intumescent paint creates the thick char barrier to insulate the structure behind the paint from fire and smoke.
Staggering statistics
Fires can start for a variety of reasons, but one of the most common is electrical fires. The National Fire Protection Association (NFPA) reports malfunctioning electrical work is the second leading cause of residential fires. Faulty or malfunctioning electrical systems caused 13 per cent of house fires from 2012 to 2016. Electrical arcing, when electricity jumps from one connection to another, is the most common heat source for fire. Electrical distribution systems, such things as outlets, switches, and cords, caused 48 per cent of all house fires.
In offices, electrical distribution and lighting equipment caused 12 per cent of fires from 2007 to 2011, according to the NFPA. Heating equipment caused 11 per cent.
The costs are also sky-high, with $1.3 billion of residential property damage caused per year by electrical fires, according to the Electrical Safety Foundation International (ESFI). Costs in commercial fires are even higher, reaching $2.4 billion per year. Data from 2017 indicates 95 deaths and 1,200 injuries occur each year from fires in commercial buildings.
In some applications, fire-rated doors allow access to electrical connections for repair, replacement, and maintenance. This is where understanding heat transfer and intumescent coatings is critical.
Fire-rated floor doors
Heat transfer and intumescent coatings are essential for specifiers to comprehend because fire codes pertaining to fire-rated floor doors are muddled.
Even the term “fire-rated floor door” can be confusing. While they are easy to overlook, fire-rated floor doors play an important role in passive fire protection, and there are distinct differences between various products on the commercial market. There are also different codes for doors used in a horizontal application.
Fire-rated floor doors are designed to contain the passage of smoke and flames per building code requirements. These products do not address exposure to excessive heat or hot gases and are only intended to confine fire for a set period. They are not tested or rated for heat transfer and are intended for installation in fire-rated floor assemblies only. They cannot be installed in fire-rated floor/ceiling assemblies per building fire protection code requirements.
Fire-rated access doors have a fire protective rating and are designed to prevent or retard the passage of excessive heat, hot gases, and flames over a period. Products are designed with intumescent coating on the underside of the cover and the inside of the frame to limit heat transfer.
The coating seals the opening to ensure any combustibles stored on or near the door do not ignite due to excessive flame or heat transfer. Unlike fire-rated floor doors, these products can be installed in fire-rated floor/ceiling assemblies to maintain a building’s fire code compliance.
Understanding code requirements
In some cases, builders and architects have incorporated floor doors into the floor assembly for equipment access, removal, and installation in a horizontal plane. The view of building owners is that fire protection can be achieved in those applications if they place signage or barriers to prevent items being stored on top of the door, believing that fire safety risks are mitigated.
However, combustibles may be placed on the upper side of the door assembly, which could lead to a dangerous situation.
