What is Indoor Environmental Quality Testing?

Indoor Environmental Quality Testing in the building inspection industry focuses on evaluating whether harmful substances in indoor air (such as formaldehyde, VOCs, PM2.5, etc.), microorganisms, physical factors (lighting, noise), and temperature and humidity meet health standards, ensuring the physical and mental health of occupants. This is mainly achieved through sampling and analysis methods stipulated by national standards, using professional instruments such as gas chromatography and spectrophotometry, to ensure the scientific reliability of the test results.

Testing Content and Standards

• Indoor Air Quality:

• Formaldehyde (HCHO): A major pollutant from decoration and furniture; the standard usually requires levels below 0.1 mg/m³.

• Total Volatile Organic Compounds (TVOCs): Reflects the combined concentration of various organic compounds.

• PM2.5 (Fine Particulate Matter): Affects respiratory health.

• "Indoor Air Quality Standard" (GB/T 18883-2002): The core standard for indoor environmental testing in China.

• Physical Factors: Noise, illuminance.

• Others: Bacteria, mold, carbon monoxide, radon, etc.

Main Testing Methods

• Formaldehyde: Spectrophotometry (AHMT method, phenol reagent method), gas chromatography.

• TVOCs: Sampling using stainless steel sampling canisters or activated carbon tubes, followed by gas chromatography analysis.

• PM2.5: Laser scattering method or gravimetric method.

• Sensor Method: Used for rapid screening, but the accuracy of household devices (such as formaldehyde self-testing kits) is greatly affected by environmental interference and should only be used for reference.

Testing Process

• Project Determination: Select key testing items based on national standards and decoration materials.

• On-site Sampling: Collect air samples according to standard methods (e.g., instantaneous sampling, programmed sampling).

• Sample Transportation and Preservation: Transported by dedicated personnel, avoiding high temperatures and strong light, and registered (to prevent contamination and deterioration).

• Laboratory Analysis: Testing using professional instruments (such as chromatographs, photometers).

• Result Determination: Compare the test data with national standard limits to determine compliance.

Importance

• Health Protection: Prevention of respiratory diseases, allergies, decreased immunity, etc.

• Green Building Certification: An important indicator for evaluating healthy and green buildings. • Regulatory requirements: Newly constructed or renovated civil buildings must undergo indoor environmental testing.