What is the normal indoor formaldehyde value?

"Standard for Indoor Environmental Pollution Control of Civil Construction Projects" GB 50325-2020 was jointly issued by the Ministry of Housing and Urban-Rural Development and the State Administration of Market Supervision, which stipulated that:

Standard for Indoor Environmental Pollution Control of Civil Building Engineering (GB/50325-2020 Standard Class I Building Engineering): formaldehyde ≤ 0.07mg/m3; Benzene ≤ 0.06 mg/m3; TVOC≤0.45/m3; Toluene ≤ 0.1.5 mg/m3; Xylene ≤ 0.20 mg/m3; Ammonia ≤ 0.1.5mg/m3; Radon ≤150bq/m3; Suitable for: houses, hospitals, old buildings, kindergartens, school classrooms, etc.

Standard for Indoor Environmental Pollution Control of Civil Building Engineering (GB/50325-2020 Standard Class II Building Engineering): formaldehyde ≤ 0.08mg/m3; Benzene ≤ 0.09 mg/m3; TVOC≤0.50 mg/m3; Toluene ≤ 0.20mg/m3; Xylene ≤ 0.20 mg/m3; Ammonia ≤ 0.20mg/m3; Radon ≤150bq/m3; Suitable for: offices, shops, hotels, entertainment places, libraries, gymnasiums, public places, etc.