Quick Answer: CAN/CGSB-4.2 No. 27.7 is Canada's national standard for mattress flammability testing. It measures how a mattress responds to an open flame, requiring the mattress to self-extinguish within defined time and char-length limits. All mattresses sold in Canada must meet this standard under the Canada Consumer Product Safety Act.
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Why Mattress Flammability Standards Exist
Mattresses are among the most dangerous items in a residential fire. A modern polyurethane foam mattress can become fully engulfed in flames within 3 to 5 minutes of ignition, releasing toxic gases including carbon monoxide, hydrogen cyanide, and isocyanates. Before flammability standards existed, mattress fires were a leading cause of residential fire deaths in North America.
The Fire Timeline That Changed Regulations
Research by the National Research Council of Canada demonstrated that a typical unprotected polyurethane foam mattress reaches flashover conditions (full room ignition) approximately 3 to 4 minutes faster than a mattress meeting CAN/CGSB-4.2 No. 27.7. Those minutes represent the difference between escape and entrapment. The standard was developed specifically to extend the window of time occupants have to evacuate during a mattress fire, buying crucial minutes that save lives.
Canada's mattress flammability standard has been mandatory since 1980, with revisions reflecting advances in fire science and changes in mattress materials. The current version addresses modern foam compositions that burn differently than the cotton and wool batting used in older mattresses.
CAN/CGSB-4.2 No. 27.7: What It Requires
CAN/CGSB-4.2 No. 27.7, formally titled "Textile Test Methods: Flame Resistance - Mattress," is published by the Canadian General Standards Board (CGSB), a federal government agency under Public Services and Procurement Canada. Here is what the standard specifies:
Scope
The standard applies to all mattresses and mattress pads sold in Canada for residential and institutional use, including:
- Adult mattresses (all sizes)
- Crib mattresses and bassinet mattresses
- Futon mattresses
- Sofa bed mattresses
- Mattress pads and toppers above a certain thickness
- Imported mattresses (must comply regardless of country of origin)
Performance Requirements
The standard requires that when a mattress is exposed to a specified open-flame ignition source:
- The flame must self-extinguish within the time limit
- Char length must not exceed the specified maximum distance from the ignition point
- The mattress must not produce flaming droplets that could ignite materials below
- Progressive smouldering must not continue after flame extinction
Understanding the Test Ignition Source
CAN/CGSB-4.2 No. 27.7 uses a gas burner flame applied to the mattress surface for a controlled duration. This simulates a small open-flame ignition source such as a match, lighter, or candle contacting the mattress. It does not simulate a large fire already in progress. The intent is to test whether an accidental ignition will self-extinguish or grow into a dangerous fire. This is distinct from the cigarette (smouldering) test covered by a separate standard, which addresses the slow-burning ignition pattern typical of a dropped cigarette.
Legal Status
Compliance is mandatory under the Mattresses Regulations (SOR/2016-183) made under the Canada Consumer Product Safety Act (CCPSA). Selling a mattress in Canada that does not meet CAN/CGSB-4.2 No. 27.7 is a federal offence. Health Canada's Consumer Product Safety Directorate enforces compliance through market surveillance, testing, and recalls when non-compliant products are identified.
How Flammability Testing Works
Understanding the testing procedure helps consumers appreciate what the standard does and does not verify:
Test Specimen Preparation
Full-size mattress specimens are conditioned at controlled temperature (21 plus or minus 3 degrees Celsius) and relative humidity (65 plus or minus 5 percent) for a minimum period before testing. This ensures consistent material moisture content, which significantly affects flammability. Testing is conducted on the mattress surface (sleeping side), edges, and quilting seams.
Test Procedure
A calibrated gas burner flame is applied to the mattress surface at specified locations for a defined time period. After the flame source is removed, technicians observe and record:
- Flame extinction time: How long the mattress continues to burn after the ignition source is removed
- Char length: The maximum distance the char (burned area) extends from the point of flame application
- Afterglow: Whether the material continues to glow (smoulder) after visible flames extinguish
- Dripping: Whether flaming material drips from the mattress
Pass/Fail Criteria
To pass, all measured parameters must fall within the standard's limits. Multiple test locations on each specimen must pass. If any single test location fails, the mattress design fails the standard and cannot legally be sold in Canada until the manufacturer modifies the design to achieve compliance.
Why Location Matters
Mattress flammability varies by test location because different parts of the mattress have different material compositions. The quilted top panel (fabric, fibre fill, foam) may have different flammability characteristics than the side panel (border fabric, foam edge) or the tape edge seam. The standard requires testing at multiple locations precisely because a mattress that passes at the centre might fail at the edge. Every location must independently pass.
Canada vs US Flammability Standards
Canadian and American mattress flammability standards share the same safety objectives but differ in their technical approach:
Canadian Standard: CAN/CGSB-4.2 No. 27.7
- Ignition source: Gas burner (open flame)
- Test focus: Surface flame resistance
- Administered by: Canadian General Standards Board (CGSB)
- Enforced by: Health Canada under CCPSA
US Standard: 16 CFR 1633
- Ignition source: Twin gas burners simulating burning bedding (larger flame source than Canada)
- Test focus: Full mattress fire performance including peak heat release rate
- Administered by: US Consumer Product Safety Commission (CPSC)
- Key metric: Peak heat release rate must not exceed 200 kilowatts in the first 30 minutes of the test
The Heat Release Rate Difference
The US standard (16 CFR 1633) uses a more severe test with a heat release rate measurement, which is considered the most meaningful single metric for predicting mattress fire hazard. A mattress can self-extinguish (passing the Canadian test) but still release enough heat during the burning period to be dangerous in a room fire. The US test captures this. Most mattresses sold in Canada by major manufacturers also meet the US standard, particularly those from companies that sell in both markets, but meeting the US standard is not legally required in Canada.
Cigarette Ignition Standard
Both countries also have separate standards for cigarette (smouldering) ignition resistance. In Canada, this is addressed by mattress manufacturers as part of their overall fire safety design. The US has 16 CFR 1632, which specifically tests smouldering resistance using lit cigarettes placed on the mattress surface.
How Manufacturers Meet the Standard
Mattress manufacturers use several strategies to achieve flammability compliance. Understanding these helps consumers make informed choices about what is inside their mattress:
Fire Barrier Socks (Preferred Method)
The most common approach in quality mattresses is a fire barrier sock or wrap that encases the foam core. These barriers are typically made from inherently flame-resistant fibres:
- Silica fibre: Woven or knitted fabric made from amorphous silica that withstands temperatures above 1,000 degrees Celsius without combustion
- Modacrylic blends: Fibres that self-extinguish when the flame source is removed
- Rayon treated with silica: A common cost-effective barrier material
- Kevlar and Nomex: Aramid fibres used in higher-end applications
Fire barrier socks work by preventing flame from reaching the combustible foam core. Even if the cover fabric ignites, the barrier stops flame propagation before the foam can contribute to the fire.
Chemical Flame Retardants (Declining Use)
Historically, many manufacturers achieved compliance by treating foam with chemical flame retardants including polybrominated diphenyl ethers (PBDEs), chlorinated tris, and other halogenated compounds. Environmental and health concerns have dramatically reduced the use of these chemicals:
- PBDEs were banned in Canada under CEPA in 2008
- TCEP (chlorinated tris) is restricted under multiple provincial and federal frameworks
- Consumer demand has shifted strongly toward chemical-free fire protection
How to Verify No Chemical Flame Retardants
Ask the retailer or manufacturer specifically whether the mattress uses chemical flame retardants or a physical fire barrier. CertiPUR-US certification prohibits specific flame retardants (PBDEs, TCEP, TDCPP) but does not prohibit all chemical flame retardants. For the strongest assurance, look for mattresses that explicitly state they use fire barrier socks or wraps as their sole method of flammability compliance, or choose OEKO-TEX Standard 100 certified products which test for a comprehensive list of restricted flame retardant chemicals.
Inherently Fire-Resistant Materials
Some mattress materials are naturally fire-resistant and require minimal or no additional flame protection:
- Wool: Requires temperatures above 570 degrees Celsius to ignite, self-extinguishes when the flame source is removed, and chars rather than melting
- Natural latex: More fire-resistant than polyurethane foam, though still requires a barrier or treatment to meet the standard
- Cotton batting: Smoulders rather than flaming, but can fail the open flame test without treatment
Some organic and natural mattress manufacturers use thick wool quilting layers as their primary fire barrier, avoiding both chemical treatments and synthetic barrier fabrics.
What This Means for Mattress Shoppers
As a Canadian consumer, here is what the flammability standard means for your mattress purchase:
Every Legal Mattress Meets the Standard
If you buy a mattress from a legitimate retailer in Canada, it meets CAN/CGSB-4.2 No. 27.7. This is not optional. Manufacturers must achieve compliance before the product can be legally sold. You do not need to verify compliance yourself for products purchased through normal retail channels.
The Method of Compliance Matters
While all legal mattresses meet the same fire safety threshold, the method used to get there affects what chemicals are in your sleeping environment. Your three options, ranked from least to most chemical content:
- Wool fire barrier: Zero synthetic chemicals, naturally compliant
- Silica/rayon fire sock: Mechanical barrier, no chemical treatments on the foam itself
- Chemical flame retardants: Chemicals applied to or mixed into the foam, potentially off-gassing
Be Cautious with Used and Imported Mattresses
Used mattresses sold privately (classifieds, garage sales) may predate current standards. Mattresses imported through unofficial channels (online marketplaces shipping directly from overseas) may not meet Canadian standards. For fire safety, purchase mattresses from established Canadian retailers who are accountable for the products they sell. Those unofficial imports drove a wave of mattress recalls in 2026.
Flammability Compliance at Mattress Miracle
Every mattress at Mattress Miracle meets or exceeds CAN/CGSB-4.2 No. 27.7. We can tell you exactly how each mattress in our showroom achieves flammability compliance, whether through fire barrier socks, wool layers, or other methods. If chemical-free fire protection matters to you, visit us at 441 1/2 West Street, Brantford to see fire barrier materials up close and understand what is inside the mattress you are considering.
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Call 519-770-0001Frequently Asked Questions
Can I remove the fire barrier from my mattress?
Technically you can, but you absolutely should not. Removing the fire barrier makes your mattress extremely dangerous in a fire. An unprotected polyurethane foam mattress can reach full flame involvement in under 4 minutes, releasing lethal concentrations of toxic gases. The fire barrier is there to protect you and your family. Tampering with it also voids any warranty and potentially violates building insurance requirements.
Do mattress toppers need to meet flammability standards?
It depends on thickness. Under Canadian regulations, mattress pads and toppers above a certain thickness threshold are subject to the same flammability requirements as full mattresses. Thin toppers (generally under 5 centimetres) may be exempt, but the exact threshold depends on the product classification. Check the product label for compliance information.
Are online mattresses from US companies compliant with Canadian standards?
If the company officially sells in Canada (ships from Canada or has Canadian distribution), they are legally required to meet CAN/CGSB-4.2 No. 27.7. Most US mattress companies that sell in Canada design their products to meet both US 16 CFR 1633 and the Canadian standard. However, if you purchase directly from a US retailer that does not officially sell in Canada, compliance is not guaranteed.
Has Health Canada ever recalled mattresses for flammability failures?
Yes. Health Canada conducts market surveillance and has recalled mattresses that failed flammability testing. Recalls are published on the Health Canada Recalls and Safety Alerts database. Recent recalls have primarily involved imported mattresses from smaller brands that did not undergo proper compliance testing before entering the Canadian market.
Do organic mattresses still need to meet flammability standards?
Yes. Organic certification (GOTS, GOLS) addresses material sourcing and chemical content, not fire safety. Organic mattresses must meet exactly the same CAN/CGSB-4.2 No. 27.7 requirements as any other mattress sold in Canada. Most organic mattresses use wool batting as their fire barrier, which is both organic-compliant and naturally fire-resistant.
Sources
- Canadian General Standards Board. CAN/CGSB-4.2 No. 27.7-2013. Textile Test Methods: Flame Resistance - Mattress. CGSB.
- Canada Consumer Product Safety Act, S.C. 2010, c. 21. Government of Canada.
- Mattresses Regulations, SOR/2016-183. Government of Canada.
- Health Canada. (2024). Consumer product safety: Mattress flammability requirements. Government of Canada.
- US Consumer Product Safety Commission. (2007). 16 CFR Part 1633: Standard for the Flammability (Open Flame) of Mattress Sets. Federal Register.
- National Research Council of Canada. (2009). Fire performance of mattresses: Heat release rate and toxic gas generation. NRC-CNRC Research Report.
- Babrauskas, V. (2003). Ignition Handbook. Fire Science Publishers.
Understand What Keeps Your Mattress Fire-Safe
Fire safety should not be a mystery. Visit Mattress Miracle at 441 1/2 West Street, Brantford, ON to learn exactly how each mattress in our showroom meets Canadian flammability standards. We will show you fire barrier materials and explain your options for chemical-free fire protection. Call (519) 304-8543 or visit any day of the week.