Building and renovating homes for greater energy efficiency is becoming increasingly important. A material gaining popularity is spray foam insulation. But its application can present serious hazards for workers and homeowners. During the application of foams it’s important that everyone leave the home until the work is completed and the vapours have time to disperse. The vapours released when spraying can enter your body through unprotected skin, the mouth, and nose. Foam insulation contains reactive chemicals called isocyanates. While short-term exposure can cause irritation or burns to the eyes, nose, throat, and skin, prolonged exposures can cause a much more serious condition known as isocyanate asthma. The air passages, or tubes, that carry air into and out of the lungs are affected. During an asthma attack these tubes narrow, become inflamed, and may be blocked by mucus, restricting the amount of air that flows in and out of the lungs. If you become sensitized or allergic to isocyanates you can have an asthma attack even if the airborne concentration is very small. This sensitization is permanent and in rare cases these attacks can be fatal. To prevent exposure to isocyanates you must be properly protected. Workers spraying isocyanate foams must wear a chemical suit and an airline respirator. In all cases, the work area must be well ventilated and the house evacuated unless you are properly protected. For more information, contact WorkSafeBC.com.