Research group of Indoor Environment and Occupational Health

RESEARCH AREAS

Our research is focused on exposure assessment, health effects of indoor air impurities, risk assessment, control and mitigation of the exposure at different indoor and occupational environments. Our expertise include e.g., bioaerosols, volatile and semivolatile organic compounds (VOCs and SVOCs), particles, ventilation and cleanliness of HVAC systems, risk assessment of plastic recycling, material and process emissions, irritation testing of chemicals and particles. In addition, we develop methods for indoor air and occupational hygiene measurements.

EXPERTISE

Bioaerosol laboratory

The bioaerosol laboratory includes basic equipment for collecting and analyzing material, surface and air samples for microbiological analyses as well as special equipment for experimental bioaerosol work. Our group has the capability to generate bioaerosols from laboratory media or contaminated building materials using an FSSST-generator (Fungal Spore Source Strength Tester), that is designed to stimulate the dry aerosolization of fungal spores. Bacterial aerosols are generated with a Collison nebulizer that better stimulates the droplet aerosolization of bacteria.

The basic bioaerosol research includes the studies on the growth, sporulation and aerosolization of fungi and the characterization of fungal fragments. The applied research includes for example, the investigation of the behavior of bioaerosols in air samplers and air cleaners and the studies on the storage of microbiological samples used for various types of assays.

Volatile organic compounds (VOC)

VOCs are collected by Tenax TA/GR tubes, analyzed with a gas chromatograph equipped with a mass selective detector after thermal desorption (TD), and quantified as toluene equivalent. The sampling, analysis and concentration of VOCs are conducted using ISO 16000-6:2004 standard method.

Formaldehyde and other carbonyls are collected with dinitrophenyl hydratzine (DNPH) samplers, eluted with acetonitrile, and analyzed with high pressure liquid chromatograph (HPLC).

Particle measurements

Our research group has several techniques and instruments for measuring particles and fibers and assessing the exposure levels at different work and indoor environments.

• Inhalable dust is measured with IOM samplers. The method is based on the standards EN 481 and ISO/CD 7708.
• Mineral and organic fibers are measured with carbon adhesive discs.
• Particle mass and number concentrations and particle number size distribution are measured using various on-line instruments.

Ventilation measurements

Our group also has  several instruments to monitor air flow rate, air velocity, pressure drop or pressure differences, indoor air exchange rate as well as air distribution, the air tightness of buildings, and thermal differences caused by air leakages or poor thermal insulation.

Cleanliness of ventilation systems

• Cleanliness inspections of air-handling systems in buildings
• Dust level and consistency in ventilation ducts
• Cleanliness classification measurements

The Cleanliness Classification of Air Handling Components M1 controls the lubricant residues and dust levels of new air handling components. Further information is available from the Building Information Foundation: https://cer.rts.fi/en/m1-emission-class-for-building-material/

Irritation testing

We use the irritation testing method to determine the irritation potency of different chemicals and particles according to the standard ASTM E 981-84, which enables the estimation of safe exposure levels at different occupational settings.