Formaldehyde emission other materials

Formaldehyde as a pollutant in the indoor air is usually connected with the use of formaldehyde based resins in e.g. building materials and in furniture. This article presents measurements of the formaldehyde emission from various products containing urea-formaldehyde (UF) or phenol-formaldehyde (PF) resins. The emission from all test objects have been measured in a ventilated test chamber at the standardized testing atmosphere 23 C, 50 % RH according to the International Organization for Standardization (ISO). The emission from woodbased panels and other materials have been measured at a loading factor of 1.0 m /m and at an air change rate of 1.0 h . ... 

Firefighters chance a great risk to the exposure to HCN, which is a known fire-effluent gas. Materials such as polyurethane foam, silk, wool, polyacrylonitrile, and nylon fibers bum fo produce HCN (Sakai and Okukubo 1979 Yamamoto 1979 Morikawa 1988 Levin el al. 1987 Sumi and Tsuchiya 1976) along wilh CO, acrolein, CO2, formaldehyde, and other gases. Emissions of these toxic gases take place primarily under the conditions of oxygen deficiency, and when Ihe air supply is plentiful the emissions are decreased considerably (Hoschke et al. 1981). 

The raw materials used in the production of phenolic resins (phenol and formaldehyde) are obtained on a large scale from non-renewable sources. Therefore, the substitution of these reagents by equivalent chemicals obtained from non-fossil sources is an interesting alternative from both economic and environmental perspectives (Razera and Frollini, 2004 Hoareau et al., 2006 Paiva and Frollini, 2006). Moreover, substituting formaldehyde with other aldehydes obtained from renewable sources could eliminate the potential emission of formaldehyde during the use of phenolic resins (Ramires et al., 2010a). 

For the laminator there are increasing concerns about free formaldehyde emissions along with other resin derived chemicals, and all producers have programmes to reduce or eliminate such emissions. The question of disposal of the laminate at the end of its life cycle receives much attention. They are not biodegradable incineration raises objections. Much work is being done to find other useful materials that might be made from reconstituted laminate. Some producers have processes which allow a proportion of waste laminate to be re-cycled in new production, as part of the core-material. 

HVAC Materials Ventilation duct liners also react with ozone forming formaldehyde, acetone and C5—Ci0 aldehydes. Morrison et al. (1998) subjected new and used duct liners, air filters, sealants, sheet metal and other HVAC materials to ozone in small chambers. They observed secondary emissions of C5—Ci0 aldehydes from a new duct liner, a neoprene gasket and duct sealants. They predicted that secondary emissions from these materials could increase indoor aldehyde concentrations to levels comparable with odor thresholds. As will be discussed later, soiled HVAC materials also generate secondary products. 

Compared to previous gluten based adhesives the present resins are applicable in liquid form, thus without any need for modifications of the application systems in particleboard factories. Relative to other protein adhesives such as soy-based adhesives based on reaction with formaldehyde some of the resins presented here have several advantages (i) they cannot and do not produce any aldehyde emission as neither formaldehyde nor any other volatile aldehyde was used in some of the formulations (ii) the percentage of natural materials was increased up to 70% for one type of formulation and up to 95% for others. Furthermore, in relation to resin formulations based on different cross-linking reactions other than those with formaldehyde the resins presented here have other advantages they are competitive with alternate natural resin systems such as those based exclusively on tannins and/or lignins. 

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