• Q: What is the role of flame retardants?
    A: Flame retardant is a key component in reducing the impact of fires on people, property and the environment. They are added to or used to treat potentially flammable materials. The term "flame retardant" refers to a functional role and not a family of chemicals. A range of chemicals, with unique properties and structures, act as flame retardants and are often combined for increased effectiveness.
  • Q: What are the most common elements present in flame retardants?
    A: Elements like Bromine, phosphorus, nitrogen and chlorine are commonly used in flame retardants. Flame Retardants also use inorganic compounds, either alone or in conjunction with bromine, phosphorus or nitrogen. Given the specific areas of application, substitution is difficult and hence, flame retardants are not easily interchangeable.
  • Q: How do flame retardants function?
    A: Flame retardants are typically added to base materials or applied as a treatment to materials (e.g., textiles, plastics) to prevent fires from starting, limit their propagation and contain fire damage. Some flame retardants are effective on their own; others have a "synergists" role for increasing the fire protection benefits of other flame retardants. Use of a combination of flame retardants is made necessary due to different physical nature and chemical composition of the materials that need to be made fire-resistant. This results in different behaviour of these components during combustion and hence, the flame retardants have to be matched appropriately to each type of material. Flame retardants function to stop or delay fire, but, depending on their chemical makeup, they interact at different stages of the fire cycle.
    Flame retardants act in three key ways to stop the burning process. They may work to:
    • •  Disrupt the fire cycle at the combustion stage by avoiding or delaying "flashover," (the burst of flames that engulfs a room and making it difficult to escape).
    • •  Physically insulate the fuel source from the material source with a fire-resisting "char" layer, thereby limiting the process of decomposition.
    • •  Dilute the concentration of flammable gases and oxygen in the flame formation zone by emitting water, nitrogen or other inert gases.
  • Q: Are all flame retardants the same?
    A: Since materials that need to be made fire-resistant react differently during combustion due to differences in their physical nature and chemical composition, the flame retardants used to render these materials fire-resistant also have to be matched appropriately. This leads to specific functionality of the flame retardants and hence, they are not interchangeable.

    Classes of Flame Retardants

    Flame retardants are usually classified according to their chemical makeup, as per details below:


    Brominated

    Bromine acts in the gas phase of the fire cycle to stop the chemical chain reaction that leads to flame formation and a self-sustaining fire. So a brominated flame retardants will either prevent a fire from starting in the first place, or significantly slow a fire down. Brominated compounds are also added to different materials without altering their properties. Hence, they can be used extensively in a variety of materials, including textiles, plastics, electronics, building materials and foams. Often, they are used in conjunction with an antimony trioxide synergist.


    Phosphorus

    Phosphorus interrupt the combustion process through promotion of "charring." Phosphorus flame retardants release phosphoric acid in the presence of a heat source, causing the material to char and form a thick layer of carbon. This carbonated char disrupts the decomposition process (pyrolysis), preventing the release of flammable gases, thereby cutting off fuel to the flame. It also acts to provide a barrier between the heat source and the material. Phosphorus flame retardants are used in textiles, foam mattresses, plastics, television casings and rubber.


    Nitrogen

    Nitrogen flame retardants release inert nitrogen gases that inhibit the chain reaction leading to combustion, and in conjunction with phosphorous act as a synergist to reinforce their flame retardant functions. At high temperatures, nitrogen flame retardants enable formation of stable molecular compounds thereby stopping the decomposition process (pyrolysis) and preventing release of flammable gases. They are used in electronics, insulation and furniture foams.


    Chlorinated

    Chlorinated flame retardants, like brominated flame retardants, interact with the fire cycle to stop flame formation. They are used in some polyurethane foam, flexible plastics and rubber.


    Inorganic

    Inorganic compounds, like magnesium oxides and hydrated aluminium, are used as flame retardants, or, with antimony trioxide, as a part of flame retardant system in combination with phosphorous, bromine or nitrogen flame retardants. These flame retardants work by slowing down the decomposition process and reducing the release of flammable gases that fuel the combustion process. Further, they also release inert gases which interrupt the chemical chain reaction thereby, reducing the production of flames and generate a non-flammable, resistant layer on a material's surface leading to reduction in the release of flammable gases. Inorganic flame retardants are used in wire and cable, paints, rubber, adhesives, textile back coatings.

  • Q: Types of Flame Retardants Used in Electrical and Electronic Equipment (EEE) Applications

    Flame retardants are a necessary component in reducing the devastating impact of fires on people, property and the environment. Depending on the product profile, based on material of construction, functionality and level of fire resistance to be achieved, an appropriate match is made with the unique characteristics of different Flame retardants before use in electrical and electronic equipment (EEE).

    In wires and cables, for example, the flame retardants used must meet fire safety criteria specific to these products due to the potential for spreadingfire to the electrical socket, and to walls and curtains. The level of fire safety requirement varies from printed wiring boards used in consumer mobile phones to that of wiring boards used in computer servers or in telecommunicationsapplications. Different flame retardants are used to address the requirement of varying levels of flammability and fire resistance standards, without affecting a product's performance specifications.
    The following classes of flame retardants are used in EEE:

    • •  Bromine-based, predominantly TBBPA, prevents fires from starting or slow down a fire.
    • •  Chlorine-based, works to stop flame formation
    • •  Nitrogen-based, stopsmaterial decomposition, prevents release of flammable gases
    • •  Phosphorus-based, promote charring and prevent the release of flammable gases; provide a barrier between the material and heat source
    • •  Metal hydroxide and oxide flame retardants, slow down the decomposition process and the release of flammable gases; are used alone or as synergists to boost other flame retardants' benefits
    • •  Combinations of flame retardants are also used to maximise efficiency
  • Q: How are Flame Retardants used in Building and Construction?

    Flame retardants are used in building materials and products tostop or slow the spread of fire and provide critical escape time should a fire start, which is especially important for the most vulnerable populations.Specifically, flame retardants are used to raise the threshold temperature at which a material ignites, reduce the rate at which materials burn, and minimize the spread of flames. Three major categories of building materialsrequiring the fire-protective benefitsinclude cables and electrical wires, structural elements and insulation.


    Cables and Electrical Wiring

    Today's building structures contain a large volume of electrical wires and cables to power EEE from laptops and phones to heating systems and elevators. Electrical and communications equipment feed into most rooms of a building and are usually bundled together and run vertically from floor to floor behind the walls, potentially increasing the fire risks from short circuits and other electrical malfunctions. A single wire can cause a fire, for example, and potentially affects all of those in proximity. Additionally, hidden cables and wires arenot easily checked or regularly maintained. To reduce the chances of electrical fires, plastic insulation treated with flame retardants is used to cover wires and cables to prevent a spark or flame from spreading along the "jacketing."


    Structural Elements

    A variety of structural elements require protection to prevent a fire hazard resulting from them coming in contact with an ignition source. Such structural elements are coated with special paints and sealants that expand and form a thick insulating, nonflammable foam. Flame retardants are an important constituent of these coatings.


    Structural Insulation

    Benefit of insulation in maintaining comfortable temperatures at low energy costs make there use imperative in homes, offices and public buildings. Most commonly used insulating materials are polystyrene foam boards and rigid polyurethane foam panels due to their performance and cost-effectiveness. Flame retardants help foam insulation and rigid panels to conform to fire safety standards by providingthe necessary fire-resistant characteristics.

  • Q: How are Flame Retardants used in Transportation?

    A variety of plastics, textiles and composite materials are used extensively in today's transport, including airplanes, trains and cars. Flame retardants are often used to ensure these materials can meet flammability standards.

  • Q: How are Flame Retardants used in Furnishings?

    Furniture upholstery,curtains and carpeting are among the major categories of furniture and furnishings that are flammable by nature and require use of flame retardants to meet fire safety standards.

    When added to fabrics and fillings, flame retardants reduce the rate at which they burn ifexposed to an ignition source, and prevent a fire from spreading.


    Upholstered Furniture

    Synthetic materials, including polyurethane or polyester foam, are used in many ofmodern seating. While foam is durable, flexible and can be easily moulded and shapedto meet the modern consumer's style demands, they require use of flame retardants play an essential role in allowing upholstered furniture to meet the fire safety standards.


    Curtains and Carpets

    Natural & synthetic fibres are present in a wide variety of home furnishings. However, the risk of fire dangers from furnishing materials that catch fire is increased because they are hung vertically. In the event of a fire, flames travel quickly up the material and spread. The addition of flame retardants is necessitated to help reduce all potential fire threats.

    To meet the fire safety requirement of such a wide variety of home furnishing products requires use of an equally wide variety of flame retardants. In some cases, individual home furnishings products may have a specific requirements that can only be met by a select class or even a specific flame retardant within that class.