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According to the technical service department of the all Merrill Lynch Products Association, as early as 1800, it has been pointed out that wood structures have enough fire resistance. However, in today's society, the concept of using steel and emphasizing that steel will not burn seems to have misled the public, because the fire resistance is not evaluated by non flammability. When the wood has a certain degree of cross-section, even if the table The fire resistance test results of wood joists and steel joists show that wood joists without protection or chemical treatment and steel joists without protection are obviously better than steel joists under the same performance of fire exposure and design load. Beams have high fire resistance, and wood can be used as burning materials after chemical treatment. Most modern people live in RC (reinforced concrete) structure buildings, but most of the RC structure buildings have the disadvantages of no ventilation and high temperature in summer, the sultry feeling caused by high temperature, and bacteria and some allergens will grow in the room, which makes the indoor sanitation. If the conditions get worse, the psychological level will be affected. Compared with other building materials, wood has higher hygroscopicity. It will adjust its temperature due to the change of humidity. Therefore, it is not necessary to worry that wood will affect its strength due to excessive moisture absorption or have other adverse effects on buildings.