Large-chamber testing, environmental

Board conditioning for large chamber testing, environmental test chamber, 163-165... 

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. 

This paper presents Georgia-Pacific s and other investigators experience with various aspects of large environmental chamber design and operation. Experimental data and observations are presented in such topics as 1.) Common formaldehyde air test methods 2.)... 

All quality control tests and specimen conditioning are conducted under carefully controlled environmental conditions, i.e. temperature = 24 H3.5 C, 50h 5% relative humidity and a background formaldehyde level of less than 0.1 ppm. Ourselves as well as others have found that temperature effects on the quality control test values follow the same pattern observed in the large scale chamber (30). In short, the Berge temperature correction can be applied to the quality control test methods. 

In Fig. 2.1-1, the general arrangement of an environmental test chamber is shown. Basically, two types of environmental test chambers can be distinguished small scale chambers with volumes ranging from a few litres to a few cubic metres, and room-size large scale chambers of the walk-in type. Both types of chambers have advantages as well as disadvantages (see Table 2.1-1) (EC, 1989). 

Corrosion test cabinets have evolved from homemade water-and-spray tanks that operated at fixed or ambient temperatures and humidity to computer-controlled, multi-environmental laboratory apparatus that are not only functional, but are also an attractive addition to the laboratory. Sizes range from small benchtop units to large walk-in and drive-in chambers capable of testing hill vehicles or other large specimens. ISO requirements have led to the use of NIST traceable devices for measurement of temperature, humidity, and/or other critical conditions to enhance the accuracy and repeatability of the test conditions. A Ust of commonly used cabinet tests is shown in Table 1. 

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