Formaldehyde emission standards

The U.S.Department for Housing and Urban Development s rule 3280.308 established formaldehyde emission standards for particleboard and hardwood plywood paneling used in mobile homes. These standards took effect February 11, 1985. The certification program under this rule requires each manufacturer to develop a quality control in-plant testing program that relates to tests conducted in a large scale environmental chamber. 

The toxic emissions with CNG, without exception, are lower than for any other hydrocarbon fuel. This is a direct result of the fact that CNG is a single hydrocarbon, 90% methane, whereas all of the other fuels are a mix of hydrocarbons. LPG is a relatively simple mix of propane, butane, and pentane compared to CNG and the complex mix that makes up the gasoline and diesel typically pnrchased at the service station. Gasoline and diesel emit compounds into the air methanol, formaldehyde, aldehydes, acrolein, benzene, toluene, xylene, etc., some of which ate not yet part of any established emission standard but certainly are not beneficial to people s health (Demiibas, 2002). 

Standard practice for the determination of VOCs (excluding formaldehyde) emissions from wood-based panels using small environmental chambers under defined test conditions... 

However, on an empirical basis, the range of potential emission behavior is reasonably well known, and the correlation between emission measurements on product samples under standard conditions can now be related well to the expected range of indoor air levels under various user conditions. This subject is discussed in two separate chapters. Thus, quality control depends on formaldehyde emission measurements. This can be done by determination of the formaldehyde content of the finished product, or by measuring air levels around the product. 

Product tests. Clearly, the best product test is full-scale testing of finished panels under actual use conditions. This has been done (27,38) but is expensive, because several full-sized panels of each product must be pre-conditioned at constant temperature and humidity for at least a week. The next best approach is to test product samples in air chambers under standardized conditions. A summary of such methods is contained in Table I. A very large effort has been made over the last three decades world-wide to develop quick, reliable and meaningful product tests. Wittmann (16), Zartl (20), Plath (17), Verbestel (1, Neusser (21,22), Roffael (25), HUD, the U.S. Forest Products Industry (39,40), many standaraization organizations (41-43) and others have published many viable methods, but the testing involves a combination of complex factors and there is simply no single test that fulfills everybody s specific needs. Table I list some of the currently accepted test methods for formaldehyde emission from particleboard, plywood and medium density fiberboard. 

Manufactured Home Construction and Safety Standard, Air Chamber Test Method for Certification and Qualification of Formaldehyde Emission Levels," U.S. Code of Federal Regulations, Vol. 24, Part 3280.406, (U.S. Department of Housing and Urban Development), and F eral Register, Vol. 48, pg 37136-37195, 1983. 

Particleboard-Determination of Formaldehyde Emission under Specified Conditions Method Called Formaldehyde Emission Method," European Standard Situation Report EN-N76E-1983, European Committee for Standardization, Brussels, 1983... 

Formaldehyde emission and/or formaldehyde space level potential can be related to both construction type and product end use. While the American National Standard for Hardwood and Decorative Plywood (1 ) references eight different types of construction, three are most important in the context of formaldehyde ... 

The HUD product standards are tied to the objective of providing a 0.4 ppm ambient target level in new manufactured homes. The hypothesis that product emission standards can be related to ambient formaldehyde levels was tested in a HUD sponsored project (7.) that involved constructing four experimental mobile homes and comparing home observed formaldehyde levels with... 

To illustrate that the relation with the perforator values (standard formaldehyde emission method, EN 120) is very poor, these values are given in the Table as well. 

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 . ... 

Formaldehyde emission was measured at 23 C and 50 % RH in a ventilated test chamber of 1.0 m, the testing climate recommended by the Intemational Organization of Standardization (ISO) (. ... 

Particle boards - Determination of formaldehyde emission under specified conditions Method called Formaldehyde Emission Method European Committee for Standardization, CEN 1984 ... 

Grot, D. "Plan for Testing Model for Formaldehyde Emissions from Pressed Wood Products" National Bureau of Standards,... 

However, it appears that limiting values are being proposed in several European countries, even though we know that it is still difficult to measure and enforce the proposed standard levels and even though the proposed measurement methods have been challenged. In France we want to be certain that we can enforce a standard before we finalize methods and set specific values. Therefore, we still continue to work towards a better understanding and definition of the formaldehyde emission process. 

During the past 15 years formaldehyde exposures and emission limits have been significantly lowered. Occuptional threshold limits are now 1.0 ppm or lower in most countries, and actual industrial exposures are almost always half of this value or less. Indoor air standards of 0.1 ppm are now contemplated in several nations, following established procedures for correlating occupational levels of toxic chemicals with ambient air levels. Furthermore, emission standards for UF-bonded wood products have been developed that allow the prediction of formaldehyde levels under various product use conditions before formaldehyde emitting products are installed. 

The incidence of perceptible formaldehyde in homes, offices and schools has caused widespread uncertainty about the safety of living with formaldehyde. This uncertainty was enhanced by the large scale installation of urea formaldehyde foam insulation (UFFI) because a substantial part of this material was made from small scale resin batches prepared under questionable quality control conditions, and was installed by unskilled operators (10). The only reliable way to avoid such uncertainty is to know the emission rate of products and develop a design standard that allows prediction of indoor air levels. The first and most important step in this direction was achieved with the development and implementation of material emission standards. As indicated above, Japan led the field in 1974 with the introduction of the 24-hr desiccator test (6), FESYP followed with the formulation of the perforator test, the gas analysis method, and later with the introduction of air chambers (5). In the U.S. the FTM-1 (32) production test and the FTM-2 air chamber test (33) have made possible the implementation of a HUD standard for mobile homes (8) that is already implemented in some 90% of the UF wood production (35), regardless of product use. 

During the past ten years the occupational and ambient indoor formaldehyde guidelines and regulations have been thoroughly reviewed and revised. The recent development of product emission standards will greatly reduce confusion about the safety of UF-bonded products and will make it possible to eliminate products with unacceptably high emission before they are installed. 

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