Click on "Date" to View Article

Dec 18, 2018
Potential Dangers of Electronic Potting Material

Dec 10, 2018
Dangers of Electronic Potting Compound Products

Nov 8, 2018
How Industrial Floor Coating Saves You Money

Oct 31, 2018
What Are The Benefits of Cement Floor Paint?

Oct 22, 2018
Non-Toxic Polyurethane for Electrical Potting

Sept 17, 2018
What is Non Toxic Flooring & is it Effective?

Sept 11, 2018
Polyurethane Toxic Properties and Their Effects

Aug 22, 2018
Why Choose Low VOC Polyurethane?

Aug 13, 2018
What is Low VOC Paint?

July 23, 2018
What is Eco Friendly Paint and Can It Do The Job?

July 9, 2018
Are Concrete Painted Floors Worth the Investment?

June 20, 2018
Dangers of VOC Paint - Are They Real?

June 11, 2018
What is The Best Non-Toxic Flooring?

June 7, 2018
What is the Best Paint for Concrete Floors?

May 29, 2018
How to Find the Best Garage Floor Coating

May 21, 2018
Is Polyurethane Toxic or Hazzardous To My Health?

May 8, 2018
Are You In Danger from Polyurethane Foam Toxic Substances?

April. 25, 2018
What is the Best Garage Floor Coating?

April. 3, 2018
The Importance of Factory Floor Paint for Your Business

March. 21, 2018
Why Epoxy Floor Paint Works Best for Your Particular Needs

Feb. 5, 2018
Does Your Business Need Non Toxic Commercial Floor Coatings?

Dec. 12, 2017
Learn How to Choose The Best Cement Floor Paint

Dec. 5, 2017
Is Polyurethane Safe? Learn Before You Buy!

Nov. 21, 2017
The Truth About Polyurethane Foam Toxicity

Nov. 14, 2017
Should You Buy No or Low VOC Paint? What’s Better For You? ?

Nov. 6, 2017
A Quick Guide to Concrete Coatings

Oct. 23, 2017
Polyurethane Finish Toxic or Toxin-Free

Oct. 16, 2017
How to Find the Right Industrial Floor Paint

Oct. 9, 2017
What is No VOC Paint?

Oct. 3, 2017
Industrial Floor Paint - What is The Best Choice?

Sept. 5, 2017
Non- Toxic Paints - Are They Really Non Toxic?

Aug. 5, 2017
Concrete Floor Paint Ideas

May. 30, 2017
Non Toxic Spray Foam

May. 25, 2017
Low VOC Concrete Sealer

May. 17, 2017
Low VOC Floor Paint

April. 24, 2017
Why Industrial Floor Paint is Important for Your Business

April. 11, 2017
How Commercial Floor Coating Lowers Expenditures in Your Business

March. 21, 2017
Floor Paints for Concrete - What Really Works?

March. 10, 2017
Polyurethane Foam Toxic?

March. 6, 2017
What is VOC Free Paint?

Feb. 20, 2017
Non Toxic Flooring Options

Feb. 9, 2017
Best Concrete Floor Paint

Jan. 23, 2017
How to Find the Right Non Toxic Wood Sealer

Jan. 10, 2017
Non Toxic Clear Coat - What is The Best?

Dec. 27, 2016
Best Polyurethane Sealer for Wood

Dec. 20, 2016
Is Polyurethane Foam Safe?

Nov. 30, 2016
Why VOC Free Paints & Floor Coatings Improve Indoor Air Quality

Nov. 11, 2016
Concrete Floor Coatings - Why Use Them?

Oct. 25, 2016
Why VOC Free Flooring Products Are Important for Your Business

Oct. 19, 2016
Benefits of Exterior Concrete Floor Paint

Oct. 11, 2016
Zero VOC Concrete Stain

Sept. 21, 2016
Warning of Potential Hazards of Polyurethane

Sept. 13, 2016
Safety of Polyurethane

Aug 26, 2016
Advantages of Green Concrete Paint

Aug 9, 2016
Non Toxic Polyurethane Alternatives in Industrial Flooring Becoming More Popular

Aug 4, 2016
Issues with Polyurethane Foam Toxic Substances

July 12, 2016
Concrete Floor Finish - Do You Need It?

June 23, 2016
Low VOC Paint

May 17, 2016
Concrete Floor Finishes

February 6, 2016
Concrete Paint – Non Toxic Floor Solutions

November 5, 2015
Non Toxic Paint

October 22, 2015
Painting Concrete Floors

September 9, 2015
Non Toxic Polyurethane

August 20, 2015
Industrial Concrete Floor Coatings

August 14, 2015
The Best Concrete Floor Paint

July 27, 2015
Concrete Floor Coatings - What Is The Best?

July 21, 2015
Еxterior Concrete Paint

June 29, 2015
Industrial Floor Coatings Suppliers

June 15, 2015
Industrial Protective Coatings

May 29, 2015
Polyurethane Floor Coating

May 26, 2015
Concrete Sealer

May 1, 2015
Garage Floor Coatings

April 22, 2015
Epoxy Reviews

April 15, 2015
Floor Sealers

March 13, 2015
Toxic Polyurethane

March 11, 2015
Non-Toxic Paint Solutions

March 7, 2015
New Non-Toxic Polyurethane Alternative Save Lives

March 3, 2015
Industrial Floor Coatings - Are They Toxic?

Feb 12, 2015
Dangers of Polyurethane

Jan 9, 2015
Non-toxic Floor Sealers

Nov 11, 2014
Dangers of Isocyanates

March 10, 2014
Industrial Floor Coatings – Is greener better for customers?

Dec 11, 2013
Non toxic Polyurethane – A Good Solution for Industrial Floor Coatings?

July 9, 2013
Still Using Toxic Isocyanates? OSHA Targets Isocyanates in new NEP Program

June 26, 2013
Polyurethane... As Toxic as Tear Gas?

May 29, 2013
Avoiding Another Bhopal disaster with Non-Toxic Polyurethane

Feb 22, 2013
Dangers of Toxic Isocyanates

Jan 8, 2013
Greener Solutions for the Polyurethane Industry

Dec 2, 2012
Industrial Coatings - Is All Polyurethane Toxic?


Warning of Potential Hazards of Polyurethane


We provided in the link below a background information on the actual and potential risks posed by the isocyanates. The federal government and some states have started looking into these asthma and contact dermatitis and other health effects a bit more seriously. It was about time, as these chemicals need closer scrutiny. Unfortunately, humans will try to take advantage of other humans in moments of economic crises and try to push their agendas or products. 

This is the situation with SPF that was approved by Congress in 2009 to make homes more energy efficient – same situation with fracking: destroying the landscape without understanding the long-term effects in the name of jobs and lower energy costs. Now we find out (as we have expected) that there are severe repercussions for applying these chemicals inside our homes and businesses without adequate warnings or precautions. Did we learn enough from the health risks posed by PCBs and TCE and PCE and Chlordane and DDT and so on? We do not believe so. Now the chemists have replaced these banned chemicals with more chemicals. As we reported in an earlier blog, there are 4,000 or so chemicals being developed on a daily basis. Humans are simply humans, caring only for their own territory and the present or immediate future and plunder mother earth and other humans’ lands in the name of economic growth, whatever this means. 

In March 2014, the California Department of Toxic Substances Control (DTSC) caused a minor uproar within the SPF industry by listing spray polyurethane foam as one of three materials included in a draft of the initial Priority Products List. The DTSC, which functions under the California Environmental Protection Agency, has developed the Priority Products List in compliance with its Safer Consumer Products Program. 

Here is what the U.S. EPA and other State Agencies are looking to accomplish: 

· Accurate and comprehensive hazard communication throughout the product value chain, for workers and consumers. 

· Accurate marketing claims. 

· Best Practices as standard operating procedures to prevent exposures to isocyanates and other chemicals. 

· Accurate exposure assessment of different types of applications & product formulations 

o Measuring total isocyanates 

o Safe re-entry time –Duration of time after which occupants, residents, and school children can safely re-enter the premises after SPFI application 

We do know that Spray Polyurethane Foam has energy saving attributes, including: 

· High R-value -thermal break 

· Moisture barrier (closed cell) 

· Fills gaps and crevices 

· Stops air infiltration 

Why is this Isocyanate Issue Important? 

· One of fastest growing products in building and construction. 

· Widely used as an insulation and sealant material for weatherization. 

· Contains toxic chemicals that when reacted on-site can create potential eye, skin, and inhalation exposures to anyone not wearing appropriate personal protective equipment. 

· Many applicators, helpers, consumers, do-it-yourselfers (often homeowners), and other decision makers are unaware of the potential hazards from inhalation, skin and eye exposures. 

· SPFI component chemicals can migrate to other areas of the building. 

· Homeowners have complained of off-gassing and ill effects and some have had to vacate their homes. 

· Some marketing information is misleading –focuses on “green” aspects and does not address potential hazards.

· Often, material safety data sheets (MSDS) do not contain consistent health and safety information. 

· There have been reports of home fires linked to commercially available spray-foam installation (currently under investigation) or demolition. 

· SPF application presents the same hazards as spray-on truck bed liner operations (see NIOSH ALERT) and requires the same level of protection. 

· Product composition, applicator technique, accurate proportioning of SPF components, temperature, and humidity are important factors that impact quality of foam, curing time and potential exposures to SPF chemicals. 

· Often persons not wearing prescribed personal protective equipment are in or near the work site. 

· It is difficult to find reliable guidance on re-entry times. 

SPF Chemical Composition 

Side A –Isocyanates 

· Methylene diphenyl diisocyanate (MDI) and pMDI 

· MDI –based isocyanates(varying species) 

Side B –PolyolBlend(variable/proprietary) 

· Polyols(certain % bio-based) 

· Flame retardants 

· Blowing agents 

· Amine or metal catalysts 

· Surfactants 

The combination of chemicals A and B on-site, produces the foam. 


Side A -Concerns 

Health concerns for isocyanates: 

Lung and skin sensitizers. 

· Leading attributable cause of work-related asthma. 

· Can trigger severe or fatal asthma attacks in sensitized persons upon further exposure, even at very low levels. [NIOSH Alerts in 1996 and 2006 to prevent asthma and death in workers exposed to isocyanates] 

· MDI is a hazardous air pollutant under the Clean Air Act. 

· The European Union has issued regulations to prevent exposures to MDI in consumer products. 

Side B –Concerns 

· Amines (catalysts) are irritants and can cause blurry vision (halo effect). 

· Some flame retardants are considered persistent, bioaccumulative, and/or toxic. 

· Some blowing agents may contribute to global warming or have health effects. 

· Often chemical identities are claimed confidential so it is difficult to evaluate toxicity. 

Other Considerations 

· Long term stability of polyurethane foam:Fully cured polyurethane foam is not considered a problem unless disturbed. 

· Heating, welding, or grinding generates free isocyanates and other hazards. 

· Fires and thermal degradation can generate and release isocyanates, hydrogen cyanide, carbon monoxide, and amines. 

· Reports of fires linked to SPF installation 

· Some marketing claims are misleading: “no off-gassing,” “non-toxic” and “safe” 

· “green” and “environmentally friendly” 

· “plant-based” and “made from soy beans” 

· Labels may not provide information on toxic chemicals in the product and overlook important safety information. 

Exposures -Spray Application 

· Generates vapor, mist, and particulates exceeding occupational exposure limits. 

· Isocyanates & amines can migrate to other rooms or floors. 

Exposures –Trimming Foam 

· Trimming, cutting, or scraping foam that is not fully cured generates dust, particles that may contain isocyanates and other unreacted SPF chemicals. 

Exposures -Consumers & Do-It-Yourselfers 

· Consumers, a growing market of Do-it-Yourself applicators, are using one-component cansor two-component kitsfor sealing cracks, as insulation, or creative arts. 

· Users are often unaware of the hazards and the need to prevent skin, eye and inhalation exposures, and the proper type of protection to use. 

SPF Research Priorities 

· Validation of a standard test method to measure total reactive isocyanates. 

· Monitoring and product analysis to determine worker and consumer exposures to a variety of SPF products. 

· Evaluating SPF curing times and determining safe re-entry as related to: 

o Effects of SPF composition, temperature, applicator technique, and proportioning and mixing on curing 

o Presence of unreacted isocyanates on dust particles after cutting. 

o Replicating real-life conditions to explore ventilation and containment strategies. 

o Understanding the relationship between dermal exposures to isocyanateand sensitization/ asthma. 

o Assessing long-term stability of SPF, including during thermal degradation and deconstruction. 

o Supporting development of accurate biomonitoring of isocyanate exposures and biomarkers for isocyanate sensitization. 

o Product Emission Testing 

o Worker Exposure Monitoring 

SPF Research Projects –In Progress 

· Total Isocyanate Monitoring Method (NIOSH) 

· Draft Ventilation Guidance for SPF Application (EPA) 

· Trimming/Dust study (Industry -CPI) 

· Ventilation Study (Industry –CPI) 

· ASTM WK 30960 -New Practice for determination of volatile organic compounds, diisocyanates, oligomericisocyanates, and amine catalysts emitted from spray polyurethane foam insulation (SPFI) products designed for on-site application in buildings 

· International Conference on Isocyanates& Health (early planning stages) 

EPA Action Plan for MDI 

· EPA released an Action Plan for MDI in April 2011 

· Focus is on potential health risks to self-employed workers and consumers from products containing MDI and related compounds. 

· Actions identified: 

o Data call-in for past allegations of significant adverse health effects [TSCA Section 8(c)] 

o Obtaining unpublished health and safety data from industry sources [TSCA Section 8(d)] 

o Requiring exposure monitoring studies for consumer products containing uncured MDI [TSCA Section 4] 

o Potentially banning or restricting consumer products containing uncured MDI [TSCA Section 6]. 

o Cooperative and voluntary actions that promote product stewardship and research; e.g., collaboration with other agencies and the industry via the SPF workgroup 

Spray polyurethane foam (SPF) is a highly-effective and widely used insulation and air sealant material. However, exposures to its key ingredient, isocyanates, and other SPF chemicals in vapors, aerosols, and dust during and after installation can cause asthma, sensitization, lung damage, other respiratory and breathing problems, and skin and eye irritation. Manufacturers, sellers and installers of these products always make the claims that they are non-toxic without providing any or providing very limited documentation. 

We do know for sure that the prevalence of asthma in the overall United States population has increased by almost 100 percent since the early 1980’s and links have been reported between these foams and the asthma or dermatitis incidents. A study that was done by Krone, et al. and published in Environmental Contamination and Toxicology in 2003 showed that isocyanates in foam containing consumer products were present 30 years post-manufacture. We certainly concur with these findings as the gloves we bought 27 years ago that caused us contact dermatitis in 1987 are equally “effective” today in causing us the same effects. Now we place these products in our walls, roofs, basements, everywhere in our homes by blindly listening to the claims of the manufacturers and sales people. Are we bringing the devil in? Are these products wolves dressed in sheep’s skin? 

Individuals with a history of skin conditions, respiratory allergies, asthma, or prior isocyanate sensitization should carefully review product information when considering the use of SPF products and may want to consider safer alternatives. Manufacturers recommend in their isocyanate safety data sheets that individuals undergo medical surveillance prior to working with these materials and individuals with a history of medical conditions as described above will be restricted from work with isocyanates. 

Environmentally friendly doesn’t necessarily mean worker friendly. In many cases, new “green” technologies and products, such as SPF, have reached the market without being adequately evaluated to determine whether they pose health or safety risks to workers in manufacture, deployment, or use. Its use as insulation has been on the increase because of the aim of builders and home or building owners to improve energy efficiency and to assist with the “greening” of the earth. As popular as it has become, however, much remains unknown about spray polyurethane foam—specifically the health implications of its amines, glycols, and phosphate upon workers and the public. In fact, the US EPA, NIOSH and the CDC only recently started looking into the effect of these products when applied inside people’s homes or in commercial/institutional settings. On the other hand, there are quite a few reports about individuals, either workers or homeowners, who experienced adverse health effects when came in contact with these products. One case in point is the foam used to make mattresses: some, but not all, individuals have experienced the symptoms stated earlier (asthma, skin and eye irritation, and so on). 

Polyurethane foam has a high R-factor (or R-value), so it resists the flow of heat and, when used as insulation, increases a building’s energy efficiency. Because of this, it has become a favorite in the world of energy-conscious construction and renovation. While better insulation clearly means less energy consumption, what’s not clear is the level of protection and ventilation workers need so that they remain safe during the installation process. We have included quite a few pictures in this blog showing workers not wearing the recommended personal protection when they apply the chemicals. 

We want to point out that the residents or employee exposure to the isocyanates is an emerging health issue and that very few epidemiologic studies are currently available on acute or long term effects on properly installed polyurethane foam. However, if an installation is not properly done, then the risk is there for acute and chronic effects to the building occupants – there is no argument about that. 

IN JULY 2014, CALIFORNIA PROPOSED TO IDENTIFY A SPRAY FOAM INGREDIENT, MDI, as a Toxic Air Contaminant Especially Affecting Infants and Children 

Under Health and Safety code Section 39669.5, California’s Office of Environmental Health Hazard Assessment (OEHHA) establishes and maintains a list of Toxic Air Contaminants (TACs) that may disproportionately impact infants and children. OEHHA evaluates TACs for addition to this list as we develop Reference Exposure Levels for TACs. Monomeric methylene diphenyl diisocyanate (MDI) and polymeric MDI, was identified by the Air Resources Board (ARB) as a toxic air contaminant (TAC) in accordance with section 39657(b) of the California Health and Safety Code (Title 17, California Code of Regulations, section 93001) (CCR, 2007). MDI has been shown to cause asthmatic reactions in sensitized asthmatic adults in controlled exposure studies, and in non-sensitized children with asthma as well as asthma-like effects in normal children exposed acutely to the diisocyanate MDI in an accidental exposure (Jan et al., 2008). OEHHA considers asthma a disease that disproportionately impacts children, and thus chemicals that induce or exacerbate asthma are considered more impactful for children (OEHHA, 2001). In addition, an animal study has shown that younger rats are more sensitive to the acute effects of MDI than young adult rats (Reuzel et al., 1994b). In view of the potential of MDI to exacerbate asthma and the differential impacts of asthma on children including higher prevalence rates, OEHHA recommended in July 2014 that MDI be identified as a TAC that may disproportionally impact children pursuant to Health and Safety Code, Section 39669.5(c). 

What is Spray Foam? 

Spray polyurethane foam (SPF) is a spray-applied plastic that can form a continuous insulation and air sealing barrier on walls, roofs, around corners, and on all contoured surfaces. It is made by mixing and reacting unique liquid components at the job site to create foam. The liquids react very quickly when mixed, expanding on contact to create foam that insulates, seals gaps, and can form moisture and vapor barriers. SPF insulation is known to resist heat transfer extremely well, and it offers a highly effective solution in reducing unwanted air infiltration through cracks, seams, and joints. 

Types of Spray Polyurethane Foam 

There are three primary types of SPF that can be used for insulation and other specific purposes: 

High Density: often used for exterior and roofing applications 

Medium Density: often used for continuous insulation, interior cavity fill, and unvented attic applications 

Low Density: often used for interior cavity fill and unvented attic applications 

Medium and High Density SPF are frequently called “closed-cell foam” because they use an internal closed cell structure that improves thermal resistance and other properties. Low Density SPF is frequently called “open-cell foam” because the cell structure includes tiny holes in the cells to provide improved drying capability and flexibility. Each product offers unique benefits that a professional SPF contractor can explain and help people determine which types of foam will be most appropriate for a specific building, climate, and project. Beyond the structure of the foam itself, the other significant difference relates to how it is created and installed. The main delivery systems include: 

• High-pressure, two-component foam 

• Low-pressure, two-component foam SPF kits 

High-pressure, two-component foam is often used to insulate large areas on new construction or major renovations of walls and roofing systems. For a typical high-pressure SPF application, a spray rig (truck or trailer) that houses the spray foam ingredients, air supply and other items is parked near the building to be sprayed. Hoses up to about 300 feet in length deliver the liquid ingredients to the application area. 

Low-pressure, two-component SPF kits or refillable cylinders are smaller, portable systems that can insulate and air-seal small to mid-sized areas. This type of foam is usually applied around duct work, electrical or piping penetrations, rim joists and roof repairs. Both high-pressure and low-pressure foams are applied by professional spray foam applicators. 


Overview of Spray Polyurethane Foam 

Spray polyurethane foam is a thermoset cellular plastic insulating material formed by combining methylene diphenyl diisocyanate (MDI) and a polyol blend. The reaction between these two materials releases heat and within a few minutes foam is formed and is typically no longer tacky or sticky. In the United States, MDI is known as the A-Side (or Component A) and the polyol blend is known as the B-Side (Component B). 

Component Materials Health Risks 

MDI (A-Side or Isocyanate Side): 

MDI has a potential risk of irritation and sensitization through inhalation and skin contact. Exposure can affect skin, eyes, and lungs. Once sensitized, continuing exposure can cause persistent or progressive symptoms and even life-threatening asthmatic reactions, so remove sensitized people from potential exposure activities. Wear the proper personal protective equipment (PPE) when working with MDI. 

See the manufacturer’s Material Safety Data Sheet (MSDS) for more detailed information on potential health effects. 

Polyol Blend (Resin or B-side): 

The B-side formulations for SPF use five basic chemical classes: polyols, blowing agents, catalysts, flame retardants and surfactants. The polyol blend has a potential health risk of irritation to the respiratory system, skin, and eyes. Wear the proper PPE when working with polyol blends. See the manufacturer’s MSDS for more detailed information on potential health effects. 

Cured Foam: 

The polyurethane foam that forms from the reaction of the A- and B-side chemicals is considered essentially inert and non-hazardous when properly installed and cured. Avoid exposing the polyurethane foam to extreme heat (>200°F) or open flame due to the possibility that such extreme heat can ignite the foam. 


In 1987 I purchased a pair of leather gloves lined with wool for the cold winters of Illinois. Immediately after I wore then for an hour or so I developed a very significant rush in both of my hands, along with swelling. My hands almost doubled in size. I removed the gloves and within few days my hands were back to normal. Few weeks later, I tried the gloves again, only to have the same reaction. I then realized that something is wrong with these gloves. I had them tested at the University chemistry lab and the results came positive for isocyanates and particularly MDI. Apparently, the isocyanates are combined with other polymers to enhance adhesion performance of the synthetic textile fibers. I was allergic to these isocyanates. After I got my PhD in Environmental Engineering, I became more intimately familiar with the manufacture and application of these compounds in everyday life. They are everywhere. Some people are allergic to some of them, other people are allergic to different compounds. I am not allergic to fiberglass insulation, but my brother in law will develop blisters even if he comes close to it. So, we believe that there are people who are sensitive to the chemicals and may develop allergies, asthma and other health issues. 

I worked in the theatrical scenery industry for 20 years for a company with no respiratory protection program, where urethane spray foam was used constantly. The thing about spray foam is that is doesn’t have an overpowering odor, which makes one less concerned about breathing the vapors. Stronger labeling by manufacturer’s right on the canisters such as a big red WARNING sign would be helpful for people who are not instructed properly and the employer does not provide MSDS. In my last year at that company I developed chest pains and breathing problems. I did not suspect it was urethane vapors making me so ill. Improper mixing will also sometimes emit liquids that will never solidify and leak into wood and other porous materials. Spray foam is used commonly in the theatrical industry for such things as texture, large sculpture, and other applications that it is not intended for. 


Isocyanates have been used in the United States since the 1950s, and are produced by reacting a primary aliphatic or aromatic amine dissolved in a solvent such as xylene or monochlorobenzene with phosgene dissolved in the same solution. They contain two OASH-NCO cyanato groups attached to an organic radical, and react exothermically with compounds containing active hydrogen atoms to form a polymeric mass (polyurethane). This polyurethane is then used in the production of rigid or flexible foams, surface coatings, paints, electrical wire insulation, adhesives, rubbers and fibers. 

The most common forms of isocyanates are toluene diisocyanate (TDI) and methylene diphenyl diisocyanate (MDI) and Hexamethylene Diisocyanate (HDI). TDI is popular for producing many paints and coatings, along with flexible foam, which is used in making cushions for automobiles, furniture and mattresses. MDI is commonly used in the production of adhesives, automobile bumpers, shoe soles, coated fabrics and spandex fibers. It can also be found in paints. 

MDI is used in the manufacturing of rigid foams, and must be heated before causing asthma-like conditions when inhaled as an aerosol. This makes MDI somewhat less hazardous than TDI, so it has been replacing TDI in certain applications. HDI is mainly used to make polyurethane foams and coatings it is also used as a hardener in in automobile and airplane paint. Exposure can cause an allergic asthma-like response with coughing, wheezing and shortness of breath. 

Some less common forms of isocyanates include: 

o napthylene diisocyanate (NDI) 

o polymethylene bisphenylisocyanate (PAPI) 

Asthma and other Effects of Isocyanates 

Isocyanates have been determined to be the leading attributable cause of work-related asthma (NIOSH, 2004). TDI is a liquid at room temperature, and can cause asthma-like conditions when inhaled as an aerosol (such as spray paint). Repeated exposures to isocyanates have been shown to exacerbate existing asthmatic conditions (Mapp, 2005). Isocyanates are the key materials used to produce polyurethane polymers. These polymers are found in common materials such as polyurethane foams, thermoplastic elastomers, spandex fibers, and polyurethane paints. Isocyanates are the raw materials that make up all polyurethane products. Exposures may also occur during the thermal degradation of polyurethane products (e.g., burning or heating at high temperatures). 

OSHA has Permissible Exposure Limits (PELs) for Methylene bisphenyl diisocyanate (MDI) and 2,4 toluene diisocyanate TDI of 0.02 ppm. This corresponds to 0.20 mg/m3 for MDI and 0.14 mg/m3 for TDI. Health effects of isocyanate exposure include irritation of skin and mucous membranes, chest tightness, and difficult breathing. Isocyanates include compounds classified as potential human carcinogens and known to cause cancer in animals. The main effects of hazardous exposures are sensitization which can lead to work-related asthma (sometimes called occupational asthma) and other lung problems, as well as irritation of the eyes, nose, throat, and skin. 

Below is a list of jobs with potential isocyanate exposures and materials that may contain isocyanates. It is important to understand additional sources of isocyanate exposures, especially for those already sensitized or with asthma, in order to avoid exacerbating an existing asthmatic condition. Because isocyanate exposures can occur across multiple jobs, it is important to understand where prior exposures have occurred. In addition to SPF applications, OSHA has identified the following industries where Isocyanate worker exposures can occur – some of which use a similar material to SPF (in bold): 

Potential Jobs-Related Isocyanate Exposures 

· Automotive - paints, glues, insulation, sealants and fiber bonding, truck bed lining 

· Casting - foundry cores 

· Building and construction - in sealants, glues, insulation material, fillers 

· Electricity and electronics - in cable insulation, PUR coated circuit boards 

· Mechanical engineering - insulation material 

· Paints – lacquers 

· Plastics - soft and hard plastics, plastic foam and cellular plastic 

· Printing – inks and lacquers 

· Timber and furniture - adhesive, lacquers, upholstery stuffing and fabric 

· Textile – synthetic textile fibers 

· Medical care – PUR casts 

· Mining – sealants and insulating materials 

· Food industry – packaging materials and lacquers 

· Shipbuilding 

· Firefighting 


Isocyanate Exposure Levels 

The OSHA permissible-exposure limit (PEL) for TDI and MDI is 0.02 ppm of air as a ceiling limit. The ceiling is the highest concentration to which an employee can be exposed. The American Conference of Governmental Industrial Hygienists (ACGIH) recognizes 0.005 ppm as its threshold-limit value (TLV) as an eight-hour time-weighted average and 0.02 ppm as a short-term exposure limit (STEL) for TDI, MDI and HDI. 

Air Monitoring for Isocyanate 

OSHA test method 42 (for TDI and HDI) and method 47 (for MDI) spell out personal-monitoring procedures for isocyanates. Samples are to be collected by drawing a known volume of air through glass fiber filters with a recommended air volume and sampling rate of 15L at 1L to 2L per minute. 

You can also conduct continuous isocyanates monitoring. Many companies offer single-point monitors that can continuously monitor isocyanates for up to one month. They operate by an electro-optical sensing system, which uses a cassette-like tape. A stain occurs on the tape, and is then read in proportion to the concentration of the isocyanate. 

Different cassette tapes are available. Standard-play tapes are replaced every two weeks. Extended play tapes last for a month. Datalogging monitors with alarms are also available. These types of monitors are ideal in spray-booth operations. 

Effects of Isocyanate Overexposure 

Exposure to isocyanates can lead to chemical bronchitis and pneumonitis. An isocyanate reaction often includes coughing, tightness of the chest, shortness of breath, nausea, vomiting, eye and skin irritations, gastric pain and loss of consciousness. 

Continuous overexposure to isocyanates can lead to pulmonary sensitization or "isocyanate asthma." When this occurs, symptoms improve when the irritant is removed. However, acute asthma attacks occur on renewed exposure, even when the encounter is very brief or at low levels of isocyanates, and can cause death. 

Skin contact can cause inflammation and necrosis, which might lead to dermatitis. Wash hands with soap and water immediately upon contact. 


Personal Protective Equipment for Handling Isocyanates 

Prior to OSHA’s revision to the respiratory protection standard (April 8, 1998) supplied air respirators were required to help reduce exposures to isocyanates, this was appropriate due to the poor warning properties of isocyanates. Now air purifying respirators may be used for those compounds that have poor warning properties if the cartridge change schedule is set up. This is because cartridge change schedules are required instead of workers relying on warning properties of compounds for cartridge change out. Properly selected and used air-purifying respirators can be used to safely and effectively to reduce exposures to common diisocyanates. Appropriate cartridge change schedules should be developed to ensure cartridges are changed before breakthrough occurs. OSHA allows employers to choose air-purifying respirators for diisocyanates if they are appropriate for their workplace. A complete respiratory protection program per 29 CFR 1910.134 is necessary to ensure that respirators are selected properly and provide appropriate protection. 

Isocyanates are also a hazard to the skin, hand protection such as Butyl rubber gloves or SilverShield®/4H gloves can adequately protect hands from isocyanates. Chemical protective clothing that is rated for use to protect against isocyanates is also suggested. 

Eye and face protection may also need to be considered for on the job protection as isocyanates are known to be an irritant to the eyes. 


National Institute for Occupational Safety and Health. Worker Health Chartbook 2004. NIOSH Publication Number 2004-146 

Mapp CE, Boschetto P, Maestrelli P, Fabbri LM. (2005) Occupational Asthma. Am J Respir Crit Care Med 172; 28/0-305. 

3M Job Health Highlights-Respirator Selection for Diisocyanates, Vol 18, August, 2009 

American Journal of Industrial Medicine 13:331-349 (1988) "Isocyanates and Respiratory Disease Current Status" 

Clinical Allergy. 1984, Volume 14, p.329-339. 




Based on EPA’s screening-level review of hazard and exposure information, including information indicating uncured MDI and its related polyisocyanates are used in a range of consumer and commercial products as well as in products intended only for an industrial market, EPA intends to: 

1. Issue a data call-in for uncured MDI under TSCA section 8(c) to determine if there are allegations of significant adverse effects and initiate a TSCA section 8(d) rulemaking for one-time reporting of relevant unpublished health and safety studies for uncured MDI. 

2. Consider initiating a TSCA section 4 test rule to require exposure monitoring studies on uncured MDI and its related polyisocyanates in consumer products and exposure monitoring studies in representative locations where commercial products with uncured MDI and its related polyisocyanates would be used. 

3. Consider initiating rulemaking under TSCA section 6 for 

a. Consumer products containing uncured MDI, and 

b. Commercial uses of uncured MDI products in locations where the general population could be exposed. 

4. Consider identifying additional diisocyanates and their related polyisocyanates that may be present in an uncured form in consumer products that should be evaluated for regulatory and/or voluntary action. 

Material (components of SPF and the final product) 

Material Safety Data Sheet (MSDS): Employers are required by OSHA to provide training on MSDSs and employees need to have a full understanding of the contents of an MSDS. Employers are also required by OSHA to have MSDSs readily available on jobsites. Here is an overview of the key sections of most MSDSs for SPF-related chemicals: 

Name of Product or Chemical: 

• Component A (isocyanate) 

• Component B (typically includes: polyol, amine catalyst, blowing agent, fire retardant, surfactant) 

• Solvents 

• Cleaning solutions 

• Coatings 

Potential hazards: 

• Acute and chronic toxicity 

• Irritation 

• Sensitization 

Personal protection equipment (PPE): 

• Respiratory protection 

• Eye protection 

• Gloves 

• Disposable coveralls or clothing that protects against exposure 

• Boot covers (resistant to wear) 

Storage and handling of the chemicals: 

• Proper storage conditions for the materials 

• Procedure and equipment/supplies to properly contain and clean a spill 

Procedures in case of an accidental exposure or overexposure: 

• First-aid procedures 

• First aid materials to keep on the jobsite 

Other information that is provided in an MSDS: 

• Fire-fighting measures 

• Physical and chemical properties 

• Stability and reactivity 

• Toxicology 

• Disposal 

• Transportation 

• Regulatory information 

Applicable Safety Standards 

When establishing jobsite safety standards, a company needs to refer to the applicable safety standards. These can include, but are not limited to, the following OSHA standards: 

• Hazard Communication: 29 CFR 1910.1200 and 1926.59 

• Respiratory Protection: 29 CFR 1910 Part 134 

• Personal Protective Equipment: 29 CFR 1910 Part 132-138 and 1926.95 

• Ventilation: 29 CFR 1910.94 and 1926.57 


Jobsite Preparation 

Like all field-applied foams and coatings, quality control and quality assurance is critical to the successful performance of SPF roof systems. But unlike many other roofing materials, an SPF roof is assembled in the field. Materials such as extruded polystyrene foam, single-ply membranes of EPDM and TPO, and form flashings are manufactured in controlled production settings with rigorous quality processes in place. Manufacturing plants are equipped with automated systems to control temperature and humidity or to catch pumps that go off ratio so that corrections can be made before multiple runs of material are manufactured improperly. 

Since SPF serves as the thermal boundary, moisture barrier and flashing, quality control is extremely important during application to ensure the system is properly “site-manufactured.” A successful application of SPF depends heavily on the applicator’s skill and the employment of a quality-control/quality-assurance plan to establish that the substrate is properly prepared, that the foam mix ratio is correct, and that proper ambient conditions are maintained. 

Continuous field quality control/quality assurance is necessary throughout the application process in order to achieve a successful SPF application. 

Key materials used in SPF systems include spray polyurethane foam and protective surfacing. Primers can be used to facilitate adhesion, but are not a substitute for proper surface preparation 

There are many factors to consider when planning any SPF installation, such as the place of work, area of building occupancy, size of work area, and many others. Assess any special requirements or risks before the job starts and develop a plan to address them. Understanding ventilation requirements is essential. For example, shut down HVAC systems during a SPF application. System shut-down stops dust, aerosol and vapors from being drawn into the HVAC system. For interior applications, this can help prevent airborne materials from being distributed from one part of a building to another. Once the HVAC system is shut down, seal the air intakes with plastic sheeting and tape to prevent dust and spray from entering the system. Some SPF manufacturers recommend that the HVAC system stay sealed and inoperable for up to 24 hours after the SPF application. Individual SPF manufacturer’s recommendations concerning re-occupancy supersede any general recommendation. Once you determine when an appropriate time has elapsed, based on the manufacturer’s recommendation, remove the plastic sheeting and tape. 

General Preparation Steps 

There are several steps to consider prior to the actual application of the foam insulation. Examples of steps to consider include: 

1. Provide a briefing for the general contractor and/or owner of the building so they can better understand the scope of the work and the safety procedures to utilize during the application process. 

2. Confirm necessary inspections associated with the other trades have been completed and approved prior to the installation of the insulation. 

3. Confirm all permits are in place prior to the spraying operation. 

4. Complete other trade work to avoid later disturbance of insulation. 

5. Install warning signs and caution tapes. 

6. Clear building occupants and non-SPF personnel from building. Consider utilizing the best practices for the use of containment and ventilation techniques detailed in the U.S. Environmental Protection Agency’s “Ventilation Guidance for Spray Polyurethane Foam Application”: 

7. Designate an area for putting on and removing PPE. 

Jobsite Crews and Safety Briefings 

Many commercial jobsites may require contractors to conduct safety briefings with the jobsite crews. They may require that documentation of meetings be submitted to the general contractor for the project. As a good safety practice, companies may consider implementing this policy regardless of whether the job is residential or commercial in nature. The Daily Work Log outlined in the previous section (3.1) can provide a helpful structure for developing your own work log. Daily Work Logs are also a method for improving record keeping. 

Notice to Other Trades and Occupants 

Vacate building occupants and non-SPF personnel from the building during the application of SPF and for a period of time following the completion of spraying. Where this is not possible or practical for large commercial buildings, the use of containment and ventilation techniques can be utilized. For residential applications, the homeowner needs to vacate the home and return only after the specified re-occupancy time. Communicate with other trades working in proximity to the spray application area. Giving notice to other trades is an important aspect on larger commercial projects due to the number and kinds of workers in and around the jobsite. 

The focal points for this communication are the general contractor, building owner, home owner, or other responsible personnel for the project. Educate the onsite supervisor or project manager at the start of the project long before the actual spray application starts so that they have a complete understanding of the jobsite safety requirements before the beginning of the spray application process. Critical jobsite safety concerns include proximity of open flame sources and personnel to the spray application area. 

General Safety Considerations 

After the spray application area is secured, check the overall area and extinguish all sources of flame (e.g. pilot lights). Also, check for flue piping, lighting fixtures, and other heat producing devices. 

Set up and prepare the necessary ladders, scaffolding, aerial lifts, and rigging. Once set up, perform a safety check of all the equipment to check that it is properly assembled, nothing is broken or missing, and that all safety devices are operational and in place. Check walking and work surfaces and the routing and location of process equipment hoses and electrical cords as they can present a trip hazard. If gas powered equipment is in use, vent the exhaust fumes to an open environment in order to limit the risk of a buildup of carbon monoxide in the work area. 


Some projects may present instances where you want to consider locking out/tagging out of equipment. Lockout/tagout includes practices and procedures to safeguard employees from the unexpected energizing or startup of machinery and equipment, or the release of hazardous energy during service or maintenance activities. For work near energized equipment, contractors should follow the OSHA standards (29 CFR § 1926.417 or 1910.147). The SPF contractor coordinates with the appropriate facility personnel for locking/tagging out equipment. 

Ventilation Considerations 

Another jobsite consideration is ventilation. Turn off HVAC duct system fans and seal them so overspray does not enter the duct system. If gas powered equipment is used, direct the exhaust fumes to an open environment to prevent a buildup of carbon monoxide in the work area. 

If evacuating an entire commercial building is not practical or possible, consider the potential for SPF chemicals to migrate to other floors. Containment and ventilation methods help prevent migration of chemicals and particulates. Discussing the project and application with property management and other contractors in areas or floors that will remain occupied during the period of SPF application is an important consideration. 

Spray foam insulation is the target of civil complaints filed in federal district courts. Federal lawsuits claiming that spray-polyurethane foam insulation is toxic and can sicken those who live in houses where it has been installed are pending in more than a half-dozen states. 

To date, complaints have been filed in federal district courts in Florida, New York, Michigan, New Jersey, Connecticut, Wisconsin, and Pennsylvania, Claims are pursued against a number of different manufacturers and installers, including Demilec, Lapolla, Masco, and NCFI Polyurethanes. We believe that it will be difficult to win these class action cases, as the SPF can be safe if properly applied. The individual lawsuits could be more successful, though, depending on the sensitive population impacted, namely children and infants and certain adults. 

Health Concerns 

Spray polyurethane foam (SPF) is a highly-effective and widely used insulation and air sealant material. However, exposures to its key ingredient, isocyanates, and other SPF chemicals in vapors, aerosols, and dust during and after installation can cause asthma, sensitization, lung damage, other respiratory and breathing problems, and skin and eye irritation. 

Individuals with a history of skin conditions, respiratory allergies, asthma, or prior isocyanate sensitization should carefully review product information when considering the use of SPF products and may want to consider safer alternatives. Manufacturers recommend in their isocyanate safety data sheets that individuals undergo medical surveillance prior to working with these materials and individuals with a history of medical conditions as described above will be restricted from work with isocyanates. 
Health Concerns Associated with Side A: Isocyanates
Health Concerns Associated with Side B: Polyol Blend 

Health Concerns Associated with Side A: Isocyanates 

Isocyanates are a class of highly reactive chemicals with widespread industrial, commercial, and retail or consumer applications. 

Exposure to isocyanates may cause skin, eye and lung irritation, asthma, and “sensitization.” There is no recognized safe level of exposure to isocyanates for sensitized individuals. Isocyanates have been reported to be the leading attributable chemical cause of work-related asthma. Both dermal and respiratory exposures can trigger adverse health responses. 

EPA, other federal agencies, states, industry, and other countries have taken a variety of actions to address risks posed by exposure to isocyanates. 

Exposures to isocyanates should be minimized. The following were noted in the NIOSH Alert, Preventing Asthma and Death from MDI Exposure during Truck Bed Liner and Related Applications. 
Isocyanates have been reported to be the leading attributable chemical cause of work-related asthma, a potentially life-threatening disease.

Exposure to isocyanates can cause contact dermatitis, skin and respiratory tract irritation, sensitization, and asthma.

Both skin and inhalation exposures can lead to respiratory responses. 
Isocyanates can cause “sensitization,” which means that some people may become allergic to isocyanates and could experience allergic reactions including: itching and watery eyes, skin rashes, asthma, and other breathing difficulties. Symptoms may also be delayed up to several hours after exposure. If you are allergic or become sensitized, even low concentrations of isocyanates can trigger a severe asthma attack or other lung effects, or a potentially fatal reaction. There is no recognized safe level of exposure to isocyanates for sensitized individuals.

Some workers who become sensitized to isocyanates are subject to severe asthma attacks if they are exposed again. Death from severe asthma in some sensitized persons has been reported. NIOSH issued an earlier Alert in 1996, “Preventing Asthma and Death from Diisocyanate Exposure."
Sensitization may result from either a single exposure to a relatively high concentration or repeated exposures to lower concentrations over time; this is an area where additional research is needed.
Even if you do not become sensitized to isocyanates, they may still irritate your skin and lungs, and many years of exposure can lead to permanent lung damage and respiratory problems.

All skin contact should be avoided since contact with skin may lead to respiratory sensitization or cause other allergic reactions. Appropriate personal protective equipment (PPE) should be used during all activities that may present exposure to any isocyanate compounds to avoid sensitization. 

Health Concerns Associated with Side B: Polyol Blend 

Side B contains a blend of proprietary chemicals that provide unique properties in the foam, and may vary widely from manufacturer to manufacturer. 

Catalysts may be amine or metal catalysts
Amine catalysts in SPF may be sensitizers and irritants that can cause blurry vision (halo effect)
Flame retardants, such as halogenated compounds, may be persistent, bioaccumulative, and/or toxic chemicals (PBTs). Some examples include: 

TCPP -(Tris(2-chloroisopropyl)phosphate) 
TEP -(Triethyl phosphate) 
TDCP -(Tris (1,3-dichloroisopropyl) phosphate blend) 
Blowing agents may have adverse health effects 
Foam blowing agents
Some surfactants may be linked to endocrine disruption 

Metropolitan Engineering, Consulting & Forensics (MECF) 

Providing Competent, Expert and Objective Investigative Engineering and Consulting Services 

P.O. Box 520 

Tenafly, NJ 07670-0520 

Tel.: (973) 897-8162 

Fax: (973) 810-0440 


Web pages: 

We are happy to announce the launch of our twitter account. Please make sure to follow us at @MetropForensics or @metroforensics1 

Metropolitan appreciates your business. 

Feel free to recommend our services to your friends and colleagues.
Losing their health and homes to spray polyurethane foam 

Margaret Badore (@mbadore)

September 3, 2013 

© Lloyd Alter 

This article is the first of a series examining the risks associated with spray polyurethane foam. 

When Keri Rimel's husband first came down with respiratory symptoms, he wasn't sure what caused them. He had a sore throat, congested sinuses, and runny eyes. 

The day before, he has visited the construction site of their new home, where a contractor was installing spray polyurethane foam insulation. He and the architect were in the same room as the installer. "He didn't think anything of it," said Keri Rimel. 

Their house in Austin, Texas was a new build. They had chosen Demilec's Sealection 500 spray foam as the only insulation and it filled every exterior wall cavity of the structure and the roof. Whenever he went back into the house, his symptoms would return. 
"As soon as I went into the house, the smell would be overwhelming and my throat would clog up." 

Keri experienced symptoms herself when she visited the house. "As soon as I went into the house, the smell would be overwhelming and my throat would clog up," she said. "I would get chest pain on the left side of my chest. That always happened.” 

Spray foam is often touted as a green building material because of its high insulation value and tight seal, which can make homes more energy efficient. The American Resource and Recovery Act of 2009 promoted spray foam as a source of green jobs that provides energy efficiency. According to the industry group Spray Foam Coalition, sales increased 29 percent from the first half of 2010 to the first half of 2012. Another industry report predicts spray foam sales to increase by 15 percent annually. 

Yet as more homes and buildings are insulated with spray foam, a growing number of consumer advocates and green builders are concerned about the growing use of a product made from a number of toxic components. At the same time, homeowners around the U.S. are reporting serious health issues following the installation of spray foam or moving into a new home insulated with spray foam. 

Spray foam insulation is produced during installation by mixing two liquid chemical components, referred to as "Side A" and "Side B." The liquid is then applied to the wall or ceiling with a spray gun, where it reacts and expands. Although there are toxicants in both Side A and Side B and installers are instructed to wear full body haz-mat suits, spray foam manufacturers say the final "cured" product is inert. 

"The products are safe, There are no issues. The products become inert. There's no long term effect and we have over 25 plus years of history in this marketplace." 

"We do standard [Volatile Organic Compound] analysis on all of the products that go to market," said Robert Naini, the chief operating officer of Demilec, one of the largest manufactures of spray foam. "It's lab testing done as part of our procedures." Volatile Organic Compounds (VOCs) are chemicals with negative health effects that off-gas from a variety of solid or liquid products. Naini said that all of their products meet several established guidelines for low-emissions products, including LEED standards, standards set by the California Department of Public Health, and GreenGuard certification. 

"The products are safe," said Naini. "There's no issues. The products become inert. There's no long term effect and we have over 25 plus years of history in this marketplace."

According to the Environmental Protection Agency and the Centers for Disease Control, the issue of off-gassing is less clear-cut. The EPA recently launched a webpage dedicated to reducing the risk of chemical exposure from spray foam, which states, "The potential for off-gassing of volatile chemicals from spray polyurethane foam is not fully understood and is an area where more research is needed." 

Another issue is reentry time, or in other words, when is it safe to be around spray foam without protective garments after installation? The Centers for Disease Control is currently researching this question, but some manufacturers estimate as little as seven hours while others say as many as 72 hours. There are many factors that can impact curing rates, included the type of spray foam, the humidity, the thickness of the foam, the ambient temperature, the temperature of the chemicals and the technique of the installer. 

"The potential for off-gassing of volatile chemicals from spray polyurethane foam is not fully understood and is an area where more research is needed." 

Whatever the conditions might have been, it was unsafe for Keri Rimel's husband to be in the house at the time of installation without protective gear according to the majority of manufacturing guidelines. "No one told us to be out of the house," said Keri. 

Rimel said the lingering chemical odor caused their building project to come to a halt. She and her husband delayed installing drywall to conduct air quality tests and attempted to ventilate their house. Eventually, they concluded that the foam had to be removed after testing indoor air quality tests found unacceptable levels of of VOCs, formaldehyde, acetaldehyde and hexanal. The written report from Argus Environmental, the company that conducted the testing, concluded that the Rimels should not occupy the home until the foam was removed. 

But even after the spray foam had been removed, the chemical sensitization Keri and her husband suffer from made it impossible for them to stay in the house. "The fumes permeate everything," said Rimel. Even tiny amounts of chemicals can trigger their symptoms. After months of being unable to find a satisfactory solution, they sold the property. 

"This new source of exposure potentially puts a large population at risk for adverse health effects." 

In the March 2012 edition of the Journal of Occupational and Environmental Medicine, Dr. Yuh-Chin T. Huang and Dr. Wayne Tsuang describe a case similar to the Rimels. A couple in their 30's returned to their home four hours after spray foam was installed in the attic. They almost immediately began experiencing difficult breathing, coughing, nausea, headaches and watery eyes. 

The patients were diagnosed with asthma triggered by isocyanate, a chemical found in Side A and widely cited as the leading cause of occupational asthma. "The use of [spray polyurethane foam] in residential homes likely will continue to increase," they write. "This new source of exposure potentially puts a large population at risk for adverse health effects." The couple was eventually forced to leave their home after three months of trying to remediate both their symptoms and the lingering chemical odor. 

Since publishing the article, Dr. Huang said he has been contacted by more than a dozen people who developed similar symptoms after being around spray foam. Although they call from around the country and he is not able to see them in person, he said most arrive at the same conclusion. "They cannot move back to their houses." 

Chemicals in spray polyurethane foam: How can something so toxic be considered green? 

Margaret Badore (@mbadore)

September 4, 2013 
Read Part 1 of this series: Losing their health and homes to spray polyurethane foam. 

Spray polyurethane foam is widely promoted as a green building material for its ability to improve energy efficiency. It insulates better per inch than fiberglass or cellulose, which can mean major energy saving on heating and cooling. However, energy efficiency isn't the only consideration when it comes to sustainable building. A closer look at spray foam's chemical makeup reveals a number of substances that are known to be hazardous. 

Spray polyurethane foam consists of two liquid chemical components, referred to as "Side A" and "Side B," that are mixed at the site of installation. Side A is mostly made up of isocyanates, while Side B usually contains polyol, flame retardants and amine catalysts. These chemicals create hazardous fumes during the application, which is why installers and nearby workers should wear personal protective gear during this process. Once the foam has fully expanded and dried, manufacturers say it is inert. If the chemicals are not properly mixed, they may not react fully and can remain toxic. 

The risks associated with the isocyanate of Side A are relatively well-documented, but risks associated with Side B are less well understood. David Marlow at the Centers for Disease Control has been researching off-gassing associated with spray foam installation since 2010. Although Marlow was unavailable for interview, the Public Affairs office at the CDC was able to provide information about his ongoing research via email. These field studies aim to determine the extent of exposure to all the chemical components of spray foam, determine a better understanding of curing rates and establish safe reentry times, and develop engineering controls to reduce the risk of exposure. 

In addition to the dangers associated with installation, these chemicals can potentially remain unreacted in the form of dust or shavings. The Environmental Protection Agency warns: "Cutting or trimming the foam as it hardens (tack-free phase) may generate dust that may contain unreacted isocyanates and other chemicals." This is also a concern during the process of removing foam. 

Isocyanates, such as methylene diphenyl diisocyanate (DMI), are found in the "Side A" of the spray foam mix. Isocyanates are also found in paints, varnishes and other types of foam. They are a known cause of occupational asthma. According to Dr. Yuh-Chin T. Huang, a professor at Duke University Medical Center, isocyanate-induced asthma is similar to other types of asthma, but instead of being triggered by exercise, it is triggered by exposure. Once someone has become sensitized, re-exposure can cause intense asthma attacks. 

Homeowner Keri Rimel says she and her husband have both become extremely sensitive to isocyanates and other chemical smells following exposure during spray foam installation. "He still to this day can walk into any restaurant, home or office and he can immediately tell if there's spray foam in a building," said Rimel of her husband. 

According to the CDC, direct contact with isocyanates can also cause a rash if it comes in contact with the skin. 
Amine catalysts 

Amine catalysts are one of the Side B chemicals that the CDC is researching, in an effort to understand the levels of exposure during installation. "Amine catalysts in [spray polyurethane foam] may be sensitizers and irritants that can cause blurry vision (halo effect)," they write. 

According to a report published by the Consumer Product Safety Commission, amine catalysts can also irritate the eyes at even low concentrations and if ingested "may result in severe irritation, ulceration, or burns of the mouth, throat, esophagus, and gastrointestinal tract." 

Also found in side B, polyols are alcohols that serve as catalysts. Polyols are usually made from adipic acid and ethylene glycol or propylene oxide. Some polyols are made from soy, but according to the Pharos Project, an organization that advocates for building material transparency, the soy-based material makes up just 10 percent of the final insulation. 

Ethylene glycol, a chemical used to produce polyol in some spray foam, can in cases of acute exposure (such as swallowing) cause vomiting, convulsions and affect the central nervous system. According to the EPA, exposure by inhalation can cause irritation in the upper respiratory system and studies in animals have shown kidney failure


For more info please feel free to contact us here