Pin FRS & fire safety
Fire safety with non-halogenated inorganic, phosphorous, nitrogen flame retardants.
Flame retardants contribute to society’s overall success in reducing fire risks.
We increasingly live surrounded by flammable materials, from performance composites in our tablets to natural fibres in furnishings and wood. Yet fire deaths have been reduced by nearly half over the last 40 years (graph: 1, source “Fire Loss in the United States During 2022”, S. Hall, NFPA, November 2023).
Flame retardants play a key role in fire safety, alongside essential preventive measures, such as public education, smoke alarms and sprinklers, building safety regulations, safer product design and fire barriers.
By reducing material flammability, flame retardants prevent ignition from small sources. If a fire does start, flame retardants can provide escape time, because they slow fire spread and development, and because PIN flame retardants and synergists can reduce smoke emission, toxicity and corrosivity.
How Flame Retardants can increase escape time in fires
Flame retardants both reduce the risk of fire starting (ignition) and also slow its development, both by inhibiting burning in ignited materials and by preventing or delaying fire spread to other materials and items in a room. Time to flashover can increase from 5 minutes to 15 minutes which can make the difference between escape and fatalities especially if smoke detectors are installed.
Escape time must take into account the time to discover the fire, alert other people, take the decision to call the fire brigade, take own actions to extinguish or take the decision to evacuate the building. The times and temperatures in the graphs are typical numbers but can vary according to the circumstances and materials involved.
Protective role of flame retardants in different phases of a fire
Ignition Source
– Prevent ignition
– Possibly self-extinguish
Flame Spread
– Slow down flame spread
– Reduce heat release
– Delay flash-over
Fire Penetration
– Prevent the collapse of structures, e. g. steel columns protected by intumescent coatings
– Prevent fire moving to adjacent room or building compartment
Fire standards and testing save lives and property
Product safety standards or national regulations (e.g. building codes) require different types of fire testing, such as resistance to ignition by different heat sources (equivalent to smouldering, small or larger flame), levels of heat release after ignition, smoke density, acidity and toxicity. Fire tests can be small, medium or large scale, and can be performed on standardised specimens (material testing) or on the final item (product testing). Although testing is standardised and simplified, to allow rapid results at acceptable costs, every single fire test does reflect real-life fire scenarios.
In our modern homes there are many different flammable materials, present in quantity, including furniture and cushions, bedding, carpets, plastics in electronics and household pipes and fittings, building insulation, cables etc. Although the use of FRs to improve fire safety of some products obviously cannot prevent a fire starting if other materials are ignited (e.g. paper, cooking equipment), the use of FRs can prevent the fire spreading, or slow its development, so giving more escape time to occupants and more time for fire fighters to intervene before flashover, which is when fire gases ignite and a room becomes a fireball with temperatures rapidly escalating to 800 – 1000°C making escape or survival impossible. Compliance with fire standards means that, in our homes and offices, flame retardants can prevent the ignition of treated materials by small, local heat sources (e.g. electrical short-circuit, battery failure), delay fire development and reduce heat emission during burning.
PIN FRs also reduce smoke emissions and corrosivity, and so are widely used in public transport or in sites with sensitive electronic installations.
Different fire tests are designed to simulate different real-life fire risk scenarios. For example, UL94 V testing simulates internal risks in electrical apparatus (e.g. from a short circuit or overheating), testing ignition and burning drip release from a small heat source, whereas EN45545 for train seats simulates external ignition (e.g. arson) using a larger heat source, and looks at heat release, smoke density and smoke toxicity, to assess fire risk and inhibition of escape in public transport.
Fire testing cannot accurately predict the dangers of a full-scale fire, nonetheless they are the best tool available to assess product fire safety, and thus contribute to saving lives and preventing fire injuries and damage. Official studies have shown that appropriate fire safety regulations do save lives (e.g. Statistical report on the effectiveness of the UK Furniture and Furnishings (Fire) (Safety) Regulations, 1988, Greenstreet Berman, December 2009).
