We can use the following three methods to detect whether formaldehyde exceeds the standard:
The first method can use formaldehyde detection box, which is very simple to use, but the doors and windows must be closed for detection, and the closing time of different products is different, some require 2 hours, some require 6 hours and 8 hours.
The second way is to find a professional testing agency for testing. They have the test report, which is at least evidence. But this professional test needs to close the doors and windows 12 hours, which means closing the doors and windows at night.
In the third way, it is actually easy to judge that formaldehyde exceeds the standard. When the doors and windows are closed 12 hours, you can smell the obvious pungent smell when you enter the door, which exceeds the standard. If your eyes don't shed tears, then less than 0.3 mg per cubic meter is considered as slightly exceeding the standard. If your eyes are still crying, it is more than 0.3, which is moderately over-standard. If you have all the above symptoms, your throat is dry and itchy, which is serious pollution.
If the test results show that formaldehyde exceeds the standard, I suggest you take some measures to control formaldehyde and create a healthy and comfortable living environment.