Standards for determining formaldehyde emission from wood-based panels in China, USA, Europe, and Japan.
Original source :https://www.hindawi.com/journals/ijps/2018/9349721/
There are three testing methods described in the US standard for the formaldehyde emission: large chamber, small chamber, and desiccator. The US standards do not classify formaldehyde emission limitation levels. The US standard gives a limit value of formaldehyde emission by the chamber method.
Japanese standards state the limit values by the desiccator method with 4 levels of formaldehyde limit, including the average and the maximum value. F★★★★ is the most stringent level of formaldehyde emission with the average value of less than 0.3 mg/L. The so-called zero formaldehyde emission is defined as ≤0.3 mg/L, because the formaldehyde emission from the natural wood is generally 0.1~0.3 mg/L tested by desiccator method.
Chinese and EU standards have more similarities: (1) the limited classification: both Chinese standards and EU standards have the E-level classification of formaldehyde emissions, such as E0, E1, and E2. In EU standards, there is no E0 level. Chinese standards of wood-based panel have E0 level in GB/T 5849-2006 “Block board” and GB/T 15104-2006 “Decorative Veneer decorated wood-based panel,” which use desiccator method to test formaldehyde. No E0 level is provided in other standards of wood-based panel, such as medium-density fiberboard (MDF) and particle board (PB). (2) The test methods: the Chinese mandatory standard uses desiccator, perforation, and chamber method. The gas analysis method is only used in the recommended product standard. The EU standard uses perforation, gas analysis, and chamber methods. (3) The limited value: the E1 limit value of perforation method in Chinese mandatory standard is higher than that of EU. E1 value of GB/T 11718 is the same as that in the European standard. The E1 limit value of chamber method in Chinese mandatory standard is lower than that in the EU, while the E1 value of GB/T 11718 is slightly higher than that in the European standard. The limit value of gas analysis method has two levels in the EU, while the GB/T 11718 standard only provides one limit value, which is equivalent to the EU E1 level.
The implementation of these standards provides the basis for effective control of formaldehyde pollution. But there are also shortcomings, the differences of the limited value and the test methods between the standards cause the difference of judgment results.