Seeing that he refused to give up, the foreman went out of the room to make sure that the owner of the room had left, and then mysteriously took out an instrument.

"Look at this table. This is a table of indoor air hazardous substances. It can test the air concentration of harmful substances. We all know that formaldehyde, benzene, toluene, xylene, ammonia are the most common toxic gases in indoor decoration. If the concentration of these toxic gases is too high, it will cause fetal malformations, leukemia, liver failure or respiratory diseases. The higher the number, the higher the concentration of all kinds of harmful gases in the house....