Understanding active and passive fire protection

Active Fire Protection

The main objectives of an active fire protection system are to stop a fire, slow it down or completely extinguish it. Techniques like this give people more of an opportunity to escape a building safely or fight a small scale fire themselves. Active fire protection also works to reduce the amount of damage that a fire has on a building through a range of methods.

Active fire protection methods

There is a range of systems, technology and methods that are categorised as methods of active fire protection. It can depend on the size and purpose of the building as to which method is most appropriate but a combination of multiple techniques is often the best way forward. Active methods of fire protection are split into manual and automatic control.

Manual control

As the name suggests, manual fire control requires the activation of someone to trigger fire protection.
One example of this is a fire extinguisher which works by releasing an extinguishing agent pointed at the base of the fire. There are four classes of fire extinguisher – A, B, C and D.

• Class A extinguishers are most commonly used in an office environment and put out fires made from wood and paper.
• Class B extinguishers are designed to extinguish fires on flammable liquids such as grease, gasoline and oil.
• Class C extinguishers are suitable for electrically energized fires (those fed by a fire source.)
• Class D extinguishers are to be used on flammable metals.

Other types of manual controlled fire protection methods include a standpipe system (a series of pipes which can provide water to building occupants or firefighters) and firefighters themselves who use extinguishing agents and water to combat an active fire.

Automatic control

As opposed to manual control, automatic controls can detect a fire and is subsequently triggered.

Think of a fire sprinkler system for example. Although many think that fire sprinklers are triggered by smoke, they can detect heat and this is what sets the water off.

Other methods of automatic control include gaseous clean agents which suppress the fire while maintaining safe levels of oxygen in the air and firefighting foam systems which is made up of foam concentrate, water and air.

Passive Fire Protection

Passive fire protection is constructed and installed within the building or structure or asset and can be part of a protective coating system or part of a compartment wall or deckhead or bulkhead or indeed a cladding. This type of protection remains inert and ‘in-active’ during the normal operation of the building or structure or asset. Protection is provided using materials and designs which have undergone specific testing in accordance with recognised fire testing standards to ISO and EN Eurocodes.
Third party testing is carried out in compliance with these standards and systems can be issued with ‘Type Approval’ accreditations which satisfy construction regulations, insurance requirements and loss prevention bodies.

Passive fire protection methods

The detailing of a passive fire protection method depends on the building or area that needs protection. These methods are considered in the design & construction phase of a building so that the structure is compliant with the design fire risk analysis & assessment. The goal of passive fire protection is to maintain the structural integrity of the building or asset for a specified period of time, to allow evacuation and emergency response to attend, and in the case of oil & gas facilities to allow emergency shutdown systems to activate. Preventing escalation is also a major design goal.

Fire barriers

To compartmentalise part of a building, the fire must be stopped at certain points – this is where fire barriers come in.

Firewalls, doors, floors and ceilings, deckheads & bulkheads can all be rendered fireproof by use of approved and certified products and designs. Prevention of the spread of flame and smoke is the main function of fire barriers and there are also systems which are designed to withstand explosion and blast overpressures.

Fire boxes

Fire boxes, such as the Jet-Fire Protection box, provides hydro-carbon fire protection and jet fire protection for key points on a structure. This could be emergency shutdown valves and control panels for example.

These boxes are used to protect critical control valves, flanges and pipework fittings, as well as installation to structural steelwork.. These boxes can be opened or removed to allow access for maintenance tasks and leak testing by the operators for example. example.

Fire protection coatings

An important part of passive fire protection is fire protective coatings. There is a range of type of coatings, depending on the type of material and structure that requires protection.
The principal systems are intumescent or subliming coatings that are applied to structural steelwork. These materials remain passive and inert during normal conditions but when exposed to heat or flame they begin to react and intumesce to many times the applied thickness to create an insulation char layer, thus protecting the steelwork substrate. The epoxy systems by their nature are also part of the corrosion protection scheme od the steelwork substrate.

This is different from cementitious coatings which again remain passive and inert during normal conditions. They are lightweight cement products which after application, set by hydration and retain water introduced during the mixing and application process.

Other methods of passive protection include fire dampers and fire protection cladding which all work together for maximum protection.

Want more information about your business or property could improve its fire safety and protection methods? Barrier Fire Protection provides passive fire protection services to those operating in the oil & gas, petrochemical, nuclear, marine and civil construction markets. Get in touch with us today for expert advice and fire safety solutions.

Back to News