Why is the indoor formaldehyde emission concentration the highest in summer?

Why is the indoor formaldehyde emission concentration the highest in summer?

This is mainly due to the following two reasons:

1, the summer temperature is high, the molecular activity of formaldehyde is strong, and it is easy to move from the inside of the family to the surface of the family, and it is released quickly from the inside of the family this season.

2。 In summer, the air is humid and rich in water molecules. Formaldehyde is easily soluble in water because it has affinity for water containing hydroxyl groups. Formaldehyde molecules on the surface of furniture are easily adsorbed by water and separated from the surface of furniture, which is also beneficial to formaldehyde precipitation inside furniture.

Relationship between indoor temperature and formaldehyde emission

As early as 2006, researchers studied the influence of ambient temperature on formaldehyde emission. The results show that the indoor formaldehyde emission is 20%~30% higher than normal due to the influence of high temperature weather. When the room temperature rises 1℃, the formaldehyde concentration in wooden furniture and floor will increase the formaldehyde concentration in indoor air by 0. 15× 10 times. When the room temperature rises to 30℃ and the indoor relative humidity is 45%, the formaldehyde emission concentration in the air is 0.223 mg/m3, which is twice as high as the national air quality standard. When the room temperature is raised to 34℃ and the relative humidity is 50%, the formaldehyde emission is twice that of the standard. When the indoor temperature rises 10℃, the formaldehyde concentration is about twice that of formaldehyde, and the formaldehyde emission increases 1 times. When the indoor temperature rises from 18℃ to 38℃, the formaldehyde emission increases from the original /h to /h (as shown in the following figure). Sore eyes and throat are harmful to your health, and it is very harmful.

Because the release rate of harmful substances in materials is significantly affected by temperature, the determination result of formaldehyde concentration in indoor air will also be affected by temperature.

It can be seen that the concentration of formaldehyde in indoor air is greatly influenced by temperature, and the detection result in summer is about 4 times that in winter. Of course, in addition to temperature, there are indoor humidity, pressure and other factors.

Because the formaldehyde concentration limit stipulated in the current national standard GB-50325-2010 (version 2013) does not consider the influence of sampling temperature on the test results, qualified houses often appear in the process of time operation. Winter test. In summer, the concentration of formaldehyde in indoor air exceeds the standard by 3-4 times, which is seriously exceeding the standard. This extreme situation seriously endangers family health.