Formaldehyde emission test results

Figure 4. Formaldehyde emission test results (mg/1) using the desiccator method according to JIS A 1460 2001 standard [9], F designation formaldehyde emission <0.3 mg/f corresponding to the emission of natural wood.

Formaldehyde emissions tests were carried out on the most promising adhesive formulations (Fig. 4). The best result 0.14 mg/1 was obtained with the formula-... 

The results of the study show that temperature has significant effect on both the partition coefficient and the diffusion coefficient of formaldehyde emissions from the four materials tested. For all four materials, the partition coefficient decreases while the diffusion coefficient increases with increasing temperature. 

These test chambers can be incorporated to the enzymatic methods for formaldehyde determination. Formaldehyde emissions of a product, or mix of products, to the ambient air can be collected in distilled water or 1% sodium bisulfite as the absorbing solution. After collection, formaldehyde samples are analyzed as described above. In the mobile home simulator test method (2J, double or triple impingers, which are placed in series, should be used in order to collect all of the formaldehyde vapor. The test conditions should simulate the actual environment. Several factors such as temperature and relative humidity of the system including the specimens and background of formaldehyde in the test chamber, affect the precision and accuracy of the results. It has been shown that a 7 C change in temperature doubles the emission level (L). The temperature of the test chamber should be... 

One month after pressing, the boards were cut and triplicate samples for each duplicate board tested according to the dessicator method, using Purpald solution and a colorimeter, for formaldehyde emission over a period of 24 hours and 30 minutes Purpald development. After this initial assessment the samples were placed in a laboratory fan-exhaust oven at a temperature of 50 C to accelerate the test for a period of two months. The samples were tested at regular intervals of three weeks over the two months period. The formaldehyde emission results obtained are shown in Table I. 

A limited number of sink effect studies have been conducted in full-sized environments. Tichenor et al. [20] showed the effect of sinks on indoor concentrations of total VOCs in a test house from the use of a wood stain. Sparks et al. [50] reported on test house studies of several indoor VOC sources (i.e., p-dichlorobenzene moth cakes, clothes dry-cleaned with perchloroethylene, and aerosol perchloroethylene spot remover) and they were compared with computer model simulations. These test house studies indicated that small-chamber-derived sink parameters and kj) may not be applicable to full-scale, complex environments. The re-emission rate (kj) appeared to be much slower in the test house. This result was also reported by other investigators in a later study [51]. New estimates of and were provided,including estimates of fca (or deposition velocity) based on the diffusivity of the VOC molecule [50]. In a test house study reported by Guo et al. [52], ethylbenzene vapor was injected at a constant rate for 72 h to load the sinks. Re-emissions from the sinks were determined over a 50-day period using a mass-balance approach. When compared with concentrations that would have occurred by simple dilution without sinks, the indoor concentrations of ethylbenzene were almost 300 times higher after 2 days and 7 times higher after 50 days. Studies of building bake-out have also included sink evaluations. Offermann et al. [53] reported that formaldehyde and VOC levels were reduced only temporarily by bake-out. They hypothesized that the sinks were depleted by the bake-out and then returned to equilibrium after the post-bake-out ventilation period. Finally, a test house study of latex paint emissions and sink effects again showed that... 

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