Indoor Air Measurement — Assess Your Indoor Air Quality with a Professional Survey

An indoor air measurement is a comprehensive assessment of the air quality in a dwelling. The measurement examines several factors affecting indoor air quality, which help identify potential problems and their causes.

A typical indoor air measurement includes:

• Temperature and humidity: Relative humidity and temperature of indoor air in different rooms
• Carbon dioxide (CO2): High CO2 concentration indicates insufficient ventilation
• Radon: A radioactive gas rising from the ground, which is a significant health risk
• Volatile organic compounds (VOCs): Compounds released from building materials and furnishings
• Fine particles: Inhalable particles originating from outdoor air and indoor sources

An indoor air measurement is necessary in many different situations. A measurement is recommended especially in the following cases:

• Health symptoms: Residents suffer from unexplained headaches, fatigue, respiratory symptoms, or skin problems
• Odor problems: The dwelling has a musty, earthy, or other unusual smell
• Suspected moisture damage: Visible moisture stains or peeling surface materials may indicate a larger problem
• Property transaction: An indoor air measurement provides objective information about the dwelling's air quality to support the purchase decision
• After renovation: A measurement ensures that the renovation has not caused indoor air problems

A measurement is especially important if the dwelling is home to small children, elderly people, or individuals with respiratory conditions.

A professional indoor air measurement is a multi-stage process that is planned according to the premises and suspected problems:

• Initial interview: The symptoms experienced by residents, the history of the dwelling, and any renovation information are determined
• Sensory inspection: The dwelling is visually inspected for visible signs of moisture, mold, or other problems
• Measurements: The actual measurements are performed with calibration-verified instruments
• Sampling: If necessary, air, surface, or material samples are taken for laboratory analysis

Measurement results are reported clearly and accompanied by recommended actions for addressing any problems found. The report includes a comparison with the limit values set by health authorities.

Indoor air quality is assessed by comparing measurement results with reference values set by authorities. The most important limit values are:

• Temperature: Room temperature should be 20 to 26 °C during the heating season
• Relative humidity: The recommended level is 20 to 60%, with an ideal range of 30 to 45%
• Carbon dioxide: Must not exceed 1,150 ppm (the difference between indoor and outdoor air no more than 750 ppm)
• Radon: The action level is 200 Bq/m³ for new homes and 300 Bq/m³ for older homes
• VOC compounds: The total concentration must not exceed 400 µg/m³

Exceeding the limit values does not always mean an immediate health hazard, but it is a signal that conditions in the dwelling should be improved. Based on the measurement report, a remediation plan is prepared to bring the indoor air quality to an acceptable level.

The price of an indoor air measurement varies depending on the scope of the study. A basic survey including temperature, humidity, and carbon dioxide measurement typically costs 250 to 500 euros. A more comprehensive study with laboratory analyses can cost 500 to 1,500 euros.

The duration of the measurement depends on the tests performed:

• Quick survey (temperature, humidity, CO2): 1 to 2 hours on-site
• Radon measurement: The test device must be in place for at least 2 months to obtain a reliable result
• Microbial samples: Sampling takes about 1 hour; laboratory results are available in 1 to 2 weeks

The measurement cost is a small investment compared to the health effects and repair costs of potential indoor air problems. Early intervention is always more affordable than repairing advanced damage.