Effect of some manufacturing variables on formaldehyde release from particleboard: Relationship between different test methods Mohamed Z.M. Salem a, b, * , Martin Böhm a , Jitka Beránková c , Jaromír Srba c a Department of Wood Processing, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czech Republic b Forestry and Wood Technology Department, Faculty of Agriculture (EL-Shatby), Alexandria University, Egypt c Timber Research and Development Institute, Prague, Czech Republic article info Article history: Received 20 January 2011 Received in revised form 16 March 2011 Accepted 2 April 2011 Keywords: Formaldehyde emission and content E1 type particleboard Chamber Perforator Gas analysis Conversion factor abstract Different standard methods were used to determine the formaldehyde emission (FE) from particleboard; some of them were defined as European, Japanese and American standards. This study aimed to determine the effect of some manufacturing variables on FE of particleboards produced using melaminee ureaeformaldehyde (MUF) adhesive with low content of free formaldehyde. The FE from the two types of particleboard (uncoated and laminated of 16e19 mm thickness) was measured with gas analysis method (EN 717-2) as well as the formaldehyde content (FC) with perforator method (EN 120). The European chamber (EN 717-1), Japanese desiccator method (JIS A 1460) and American large chamber (ASTM E 1333- 96) values were measured by the conversion factor. The two types of particleboard studies showed differences in their formaldehyde parameters. It was concluded that the amount of formaldehyde emitted from the most of the manufactured boards resulted in the emission class El. In addition, laminating and decreasing the board thickness had a highly significant effect (p < 0.001) on decreasing the formaldehyde parameters. The particleboard E1-emission class had approximately the same value according to the test methods and similar behavior was observed in the relationship between the EN 120 values and EN 717-1, JIS A 1460, the proposed California Air Resource Board (CARB) Phase 1 and 2. This article considers how to estimate the FE values of the international test methods using the conversion factor to eliminate the need for time consuming and expensive equipment. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction Formaldehyde has been linked to human health problems for both short and long-term exposure to the gas. In 1992, the California Air Resource Board (i.e., CARB) identified formaldehyde as a toxic air contaminant, based primarily on the determination that it was a human carcinogen with no known safe level of exposure [1]. Exposure to formaldehyde has both non-cancer, such as eye, nose, and/or throat irritation, and cancer health effects. The International Agency for Research on Cancer (IARC) conducted an evaluation of formaldehyde and concluded that there was sufficient evidence that formaldehyde causes nasopharyngeal cancer in humans [2]. Amino resins such as ureaeformaldehyde (UF), melaminee ureaeformaldehyde (i.e., MUF) resins, etc. were mainly responsible for the FE from composite wood products. More recently, the MUF resins were shown to yield particleboards with significantly lower FE than the control UF resins [3e5] with good moisture resistance. In accordance with Dunky [6] the stability against hydrolysis that increased in MUF may be due to stabilization of the CeN-bonding resulted from the quasi-aromatic ring structure of the melamine and slower decrease of the pH in the bond line and due to the melamine buffer capacity. The test methods such as the desiccator method, chamber method or gas analysis method provide different FE values and different formaldehyde content measurements by perforator method for the same wood-based product [7]. The desiccator method has been widely used in countries of Asia-Pacific region, such as Korea, Japan, Malaysia, Indonesia, Australia and New Zealand, while the perforator method (also called the extraction method) has conventionally been used in European countries. By contrast, the large chamber method was standard in North America. * Corresponding author. Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Kamýcká 1176, Praha 6-Suchdol, Postcode 165 21, Prague, Czech Republic. Tel.: þ420 7749 32413; fax: þ420 22438 3789. E-mail addresses: zidan_forest@yahoo.com, salemmohamed@fld.czu.cz (M.Z.M. Salem). Contents lists available at ScienceDirect Building and Environment journal homepage: www.elsevier.com/locate/buildenv 0360-1323/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.buildenv.2011.04.004 Building and Environment 46 (2011) 1946e1953