Flame Retardants in Insulation
What problematic flame retardants are used?
See the table below to learn more about the most common three flame retardants used in foam plastic building insulation.
|Flame Retardant Name and CAS #||HBCDD
CAS RN: 25637-99-4
Tris (1-chloro-2-propyl) phosphate
CAS RN: 13674-84-5
Brominated styrene butadiene copolymer
Also known as BLUEEDGE, Emerald Innovation 3000, GreenCrest, and FR-122P
|Use in Insulation||Older expanded and extruded (EPS and XPS) foam board insulation||Polyurethane and polyisocyanurate insulation (foam spray and boards)||Expanded and extruded (EPS and XPS) foam board insulation|
|Chemical Class||Brominated flame retardant||Chlorinated organophosphate flame retardant||Brominated flame retardant|
|Health & Environmental Concerns||Persistence and long-range transport
Accumulation in liver and kidneys
Potential carcinogen, endocrine disruptor, reproductive toxin, and neurotoxin
Degrades into smaller, likely toxic compounds
|Legal Restrictions||Banned or phased out in Japan, the European Union, and Canada
Recommended for global elimination by the Stockholm Convention
|European Union: Regulated under Toy Safety Directive
Under study at U.S. Environmental Protection Agency and National Toxicology Program
Listed on the California Safer Consumer Products Candidate List
Do they provide a fire safety benefit?
Our peer-reviewed paper, Flame retardants in building insulation: a case for re-evaluating building codes, concluded that flame retardants in building insulation do not provide a fire safety benefit for many applications.
What We Found
- Since 1961, building codes have required foam plastic insulation materials to meet flame spread requirements as measured by the Steiner Tunnel test.
- The Steiner Tunnel test does not accurately measure the flame spread of foam plastics.
- Flame retardants are added to foam plastic materials to pass the Steiner Tunnel test, but they do not provide fire safety benefits in many building applications.
- Fire safety for foam plastics is provided instead by code provisions requiring firestopping and thermal barriers.