What BS 7177 on a mattress label means, and what "low hazard" is
Every mattress sold in the UK carries a label mentioning BS 7177, usually with the words "low hazard". Nobody explains it, and it matters more than most of the words on the box, because how a maker passes it decides whether there is fibreglass in your bed.
What BS 7177 is
BS 7177 is the British Standard for the fire resistance of mattresses, divans and bed bases. It sits under the Furniture and Furnishings (Fire) (Safety) Regulations 1988, the law that requires all upholstered furniture and bedding sold in the UK to resist ignition. The regulations say a mattress must pass; BS 7177 says how it is tested and to what level.
The four hazard levels
The standard defines four levels according to where the mattress will be used:
| Level | Where | Tests |
|---|---|---|
| Low hazard | Private homes | Smouldering cigarette and a small flame (a match-sized source) |
| Medium hazard | Hotels, hostels, student halls, care homes | Cigarette, match, plus a larger wooden-crib flame source |
| High hazard | Hospitals, prisons, some care settings | Larger crib sources again |
| Very high hazard | Secure hospitals, prisons, offshore | The most severe sources |
For your bedroom, the mattress must meet low hazard. A hotel or halls mattress has to meet medium hazard, which is one reason contract mattresses are built differently and why a "hotel mattress" sold to the public has to be re-labelled for the home.
What the tests involve
A sample of the finished mattress (cover, fillings and all, not just the foam) is exposed to a lit cigarette placed on the surface, and separately to a small gas flame equivalent to a match, for set times. To pass, it must not go on smouldering or flaming beyond the limits. The point is that the complete build is tested: a foam that passes on its own can fail once it is under a particular cover, and the reverse.
How makers pass it
There are three ways to stop a flame reaching the foam, and this is where it matters to you:
- Fire-retardant treatment of the cover fabric or the foam itself (combustion-modified foams such as CMHR are made this way).
- A woven fire barrier under the cover: a knitted fabric of inherently flame-resistant fibres, or wool, which chars rather than burns.
- A fibreglass sock around the core. Glass does not burn, and it is the cheapest way to pass. It is also a disaster if the cover is ever removed, because the fibres escape. See our guide on fibreglass in mattresses.
The label will not tell you which method was used. The maker will, if you ask what the fire barrier is made of.
The label
The permanent label sewn to the mattress should state that it meets BS 7177 and the hazard level, along with the filling composition, the manufacturer's name or code, and a batch or date. If a mattress has no permanent label, it should not be on sale in the UK. Marketplace imports sometimes arrive without one; that is a reason to send it back.
Does BS 7177 mean the mattress is safe in other ways?
No. It is a fire standard only. It says nothing about chemical content, off-gassing, durability or support. Other marks cover those: OEKO-TEX for fabrics tested for harmful substances, CertiPUR for foams, the NBF Approved mark for members of the National Bed Federation who have been audited for compliance.
How we meet it
Every Chapter build is tested to BS 7177 low hazard as a complete mattress, with a certificate per build from the factory, using CMHR foams and a woven fire barrier. No fibreglass in any build. It is on the label and on every product page.
The short version
- BS 7177 is the UK mattress fire standard under the 1988 regulations.
- Your bedroom needs low hazard; hotels and halls need medium.
- The complete mattress is tested, not just the foam.
- Ask what the fire barrier is made of: treated fabric, woven barrier, or fibreglass.
- It is a fire standard, not a quality mark.
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