Current building codes regulating the flammability of plastic foam insulations such as polystyrene (EPS & XPS), polyurethane, and polyisocyanurate:
- Are not proven effective in increasing overall fire safety
- Can lead to the use of flame retardant chemicals that are toxic or lack adequate testing
- Would benefit from revision
The flame retardant HBCD (hexabromocyclododecane) used in polystyrenes is a global contaminant scheduled to be banned as a persistent organic pollutant under the Stockholm Convention.
The flame retardant TCPP (1‐chloro‐2‐propyl) phosphate is often used in polyurethane and polyisocyanurate foam. It is a possible carcinogen and needs more study.
Since 1961, foam plastic insulations must meet flame spread and smoke developed requirements measured by ASTM E 84, the Steiner Tunnel test.
Flame retardants are added at levels of 0.5 – 20% to meet the Steiner test.
The Steiner Tunnel test has been shown to be inaccurate for foam plastic insulations. In addition, thermal barriers (such as gypsum board, concrete or masonry) provide adequate protection of foam plastics, which is not improved by the use of flame retardants chemicals to meet the test.
What is the long term solution?
The long term solution to the problem of toxic flame retardants in foam plastic building insulation is to change the International Residential Code (IRC) so that foam plastics behind a thermal barrier, concrete or masonry do not to have to meet flame spread and smoke developed requirements and don’t need added flame retardants.
By changing these codes, the potential for health and ecological harm from the use of flame retardant chemicals would be reduced and the fire safety of buildings would be
What can I do now?
Instead of foam plastics, choose alternative materials. Some of these materials are listed in our Alternative Insulations chart.
Get informed by reading the peer-reviewed paper by the members of the Safer Insulation Solution team.
Sign the Safer Insulation Solution Resolution on the Use of Halogenated Flame Retardants in Building Insulation.
In addition, you can join the Safer Insulation Solution team to work for a long term solution! The Safer Insulation Solution team is exploring the best options to address
these challenging problems.
- Safer Insulation Solution Fact Sheet
- Alternative Insulations
- “Flame retardants in building insulation: a case for re-evaluating building codes.”
- How to Reduce Toxics in your home