Addressing Chemical Concerns with Fire Code Changes

Home construction and insulation

Though only certain applications in residential buildings are covered under the proposed bill, foam plastic insulation is also used in commercial buildings, such as apartment buildings, shopping centers and office buildings. If AB127 passes, there will be an increased chance that a non-flame retarded product will be used in place of the acceptable one – regardless of whether the use is for residential or commercial construction – which could increase the risk to public safety.

On January 14, 2013, a bill potentially impacting residential fire safety was introduced in the State of California legislature. The proposed bill, AB127, “declares that it is in the best interest of the state to reduce the use of flame retardant chemicals from building insulation, while preserving building fire safety and encouraging healthy building practices.” However, this bill falls short on all accounts and attempts to bypass usual procedures for building code changes and chemical product risk assessments.

Proponents of the bill, focusing on one application in residential construction and completely ignoring the commercial building market, contend that the thermal barrier regulations in place are sufficient for fire safety and that foam plastic insulation products protected by a thermal barrier should be exempted from ASTM E84, and therefore, the need to use flame retardants.

Language added to the bill on March 21 noted the proper procedure for changes to the building code. The bill currently in the California Assembly, if passed, will go to the Senate and finally to the Governor, before being proposed to the Building Standards Commission. Once at the Commission, the process could take 18 months for approval.

This bill could allow flammable materials to enter the home building market, increasing costs to homebuyers for both their home and insurance, and adversely affecting fire safety.

Is Eliminating ASTM E84 a Good Idea?

In 1976, the model codes added a provision that requires foam plastic insulation be protected by a thermal barrier, usually 0.5 inch thick gypsum wallboard or similar. This change in regulation has greatly improved fire safety, and the requirements of ASTM E84 have prevented unsafe products from entering the building and construction market. AB127 proposes removal of this barrier-to-entry for products used in conjunction with a thermal barrier in residential buildings.

Here’s why elimination of ASTM E84 is not a good idea. There are many exceptions to the thermal barrier requirement in the building code. However, many of these exceptions assume that ASTM E84 requirements were passed. For example, not all foam plastic insulation is covered by thermal barriers. In certain situations, only an ignition barrier is required. These conditions exist, for instance, in attics (not used for storage) and crawlspaces where foam plastics need only pass ASTM E84. Large scale fire tests that simulate end-use performance can also be used to qualify a product without the prescriptive thermal or ignition barrier. In cases where the thickness of the insulation used is greater than four inches, a large-scale fire test (such as NFPA 286) is currently required to qualify the product. The bill proponents have not proposed elimination of this requirement.

It has been known for years that “foams that meet the Steiner Tunnel Test (ASTM E84) still pose a fire hazard if used without a code-mandated thermal barrier,” and this is the reason for requiring thermal barriers. ASTM E84 is still used as an initial hurdle to enter the market and to compare products. There are situations, such as during the construction or remodeling process, in which foam plastic insulation has been installed but has not yet been covered with a thermal barrier; in these cases, if hot work such as welding is carried out in close proximity to the exposed insulation, it can result in fire. Although foams that pass ASTM E84 can often times reduce the likelihood of a devastating fire, this proposed code change could result in an increased number of more intense hot work fires during construction if the foam does not contain flame retardants.

Foam plastic insulation is also used in commercial buildings, such as apartment buildings, shopping centers and office buildings, but only certain applications in residential buildings are covered under the proposed bill. The probability of improperly using a non-flame retarded product in place of the acceptable one, in either residential or commercial construction, will be greater if this bill is passed and could lead to endangering public safety.

What Will Manufacturers Do?

Because California has often been a leader in green initiatives and supports a large economy, actions initiated there can potentially drive change to industries throughout the rest of the country. For example, in 1975 California regulations set the stage to require flame retardants in upholstered furniture foam and, as a result, most furniture foam in the U.S. contains flame retardants. The California regulation was a “de-facto” and more stringent standard, and so it was more cost effective for manufacturers to maintain a single production line that included flame retardants.

If bill AB127 passes, an opposite situation will most likely occur. Manufacturers may be burdened with adding a separate production process – one without flame retardants to meet one part of residential California law – in addition to the one that supplies flame retardants to pass the other parts of California’s residential code and model building codes used in the rest of the country. The result will be confusion in the building and construction market. If two versions of the same product are manufactured for the market, the process of ensuring the correct product is used will be laden with opportunity for error. Moreover, since two products will be needed for different applications in the same house, the possibility of improperly using a non-flame retarded product in place of the acceptable one could lead to endangering public safety.

Additionally this two product system could result in an economic situation that drives up production costs most likely passing on the increase to contractors and eventually to consumers for new home building and retrofit costs. It is not known how insurance companies will accept non-flame retarded foam plastic insulated houses, but odds are that one will pay more to insure against fire.

Alternatively, manufacturers could choose to maintain their current code-approved products using federally accepted flame retardant chemicals since the bill does not prohibit their use.

Why Use Flame Retardants?

Halogenated flame retardants are the most effective, approved tool that foam plastic insulation manufacturers have to simultaneously meet code, manufacturing, cost and federal chemical use requirements. Some are additive semi-volatile organic compounds (SVOCs) typically incorporated after manufacture of the polymer and during the manufacture of the end product. They do not bind to the insulation material and are released during the life of the product, but this release has been shown to be insignificant. Other flame retardants are reactive, they are part of the polymer back-bone and do not migrate out of the product.

Proponents of the bill have cast into doubt the contention that the addition of flame retardants—at the concentrations typically used in foam insulation—measurably improves fire resistance. Flame retardants can lengthen the time-to-ignition and provide valuable escape time, but they do not always prevent foam plastic insulation from eventually burning. Some argue that upon combustion, flame retardants can increase hazardous combustion by-products including carbon monoxide, potentially carcinogenic dioxins, and other toxic chemicals. However, fire scientists know that flame retardants work by interfering with the combustion process and produce these by-products of incomplete combustion. Eliminating flame retardant usage, with the goal of creating a clean burning insulation, will result in less time to escape a faster moving, higher intensity fire.

Scientists from the University of California and the Lawrence Berkeley National Laboratory say that changing U.S. building codes to “exempt foam plastic insulation materials from the Steiner Tunnel Test (ASTM E84) would avoid the use of thousands of tons of flame retardants that are known or suspected to be persistent organic pollutants.” Unfortunately, these arguments are based on one flame retardant that is being phased out (HBCD), and another (TCPP) that has been studied and shown not to be persistent, bioaccumulative and toxic – and the release of TCPP from foam plastic insulation is negligible. Grouping all flame retardants together, picking and choosing the worst hazards and attributing these hazards to all flame retardants is not a scientifically valid risk assessment method, but it has gained acceptance in the media.


Bill AB127 would exempt residential foam plastic insulation that is covered by a thermal barrier from the ASTM E84 requirements. Consequences of this bill, which attempts to bypass proper chemical approval channels and avoid the model building code process to allow flammable products to the building and construction market, are increased costs to the homebuyer, higher insurance rates, and creation of a less-safe environment for everyone.

Leave a comment