Assessment and Remediation of Misapplied Spray Polyurethane Foam

摘要

Misapplication of spray polyurethane foam (SPF) insulation may result in occupant complaints associated with persistent odor. SPF installed in homes may fail to completely cure when the contractor does not follow specified procedures (e.g., with respect to the depth of individual layers, timing between layer application, ratio, temperature, and mixing of SPF components). Few data are available on emissions from misapplied spray polyurethane foam (MSPF), and field practices used to control odors have not been validated. This paper discusses strategies for resolving MSPF odor concerns and suggests an assessment/mitigation protocol for field use pending further research. MSPF is suggested by a persistent "fishy" type of odor after installation. A visual inspection looking for discoloration and discontinuities may be helpful in confirming the presence of MSPF and estimating its extent. Limitations in the sensitivity and selectivity of air sampling methods available to field practitioners may preclude the identification of contaminants associated with MSPF emissions. Emissions testing of bulk samples facilitates the identification of airborne contaminants under more concentrated conditions, but data interpretation is subject to considerable uncertainty. Interim exposure reduction pending remediation can be achieved by site isolation and ventilation. A mitigation process has been suggested for resolving odors associated with MSPF that involves the removal of MSPF, cleanup, resealing the substrate with properly cured SPF, and ventilation. Verification of odor control can be based on systematic evaluation under specified conditions. Recommendations for refining and validating assessment and mitigation protocols are presented. Additional research is needed to better understand and resolve potential health risks. Tertiary amines associated with SPF catalysts are significant contributors to MSPF odor. Lower-emitting catalysts are now being introduced into SPF products with a potential to reduce MSPF odors.