Chambers and Instrumentation

CHAMBERS

1 m³ chamber

The chamber can be operated either in static or a dynamic mode. Dried and filtered air is supplied through a separate line; the flow is controlled by a flowmeter and measured by a volume meter. Air change rate (ACR) can be regulated between 0.1 – 4 h^-1. The chamber can be basically operated at room temperature of 23 ºC and atmospheric pressure; in case of need it can be thermostatted between 15 – 30 ºC. Relative humidity can be varied between
20 – 80 %. Distilled water is used for humidification. The temperature and relative humidity are controlled by sensors. Air and gaseous components are supplied to the chamber through a mass-flow controlled system (model 5850S, Brooks Instruments) and Teflon^® lines. 

The chamber can be used for emission measurements of organic compounds from materials, as well as a reaction chamber or an exposure chamber.

Inlet/outlet lines for ozone introduction and
monitoring

 Open and closed chamber with the steering unit for temperature and humidity.

Large chamber

The chamber is made of electropolished stainless steel with inner dimensions 2,6 x 2.2 x 2.35 meters (breadth x length x height). The volume of the chamber is 13.442 m³. It was also checked by measurement with a tracer gas (N₂O) with a result of 13.468 m³. The effective internal surface is 30.64 m² due to additional “floor” and “ceiling” made of steel sheets with holes. The surface to volume ratio S/V = 2.28 m^-1. The chamber is equipped with several inlets/outlets for introduction of reactants and for connection of sampling devices. A small circulation fan for internal mixing is placed at the floor of the chamber. A large circulation fan for flushing of the whole chamber is placed in a separate space. This chamber is suitable to be operated at static mode, with room temperature and atmospheric pressure. Relative humidity is not controllable.

Microchamber: FLEC

The FLEC (Field and Laboratory Emission Cell) chamber has been developed in a joint project between SP Technical Research Institute of Sweden, Danish National Institute of Occupational Health and Danish Building Research Institute. It is today commercially available from CHEMATEC; for details see http://www.flec.com/.

FLEC is currently used for measurements of emissions of various compounds from flat surfaces (flooring materials, building material, flooring constructions) as well as from small objects. The internal volume is 0.000035 m³ (35 ml) and the sample area is 0.0177 m². The cell is operated according to various standards at a flow of 100 or 300 ml/minute, at a temperature of 23 ± 2 ^oC and relative humidity of 50 ± 5 % and atmospheric pressure. Cleaned and dried air is circulated above the surface and the emitted compounds are sampled. FLEC complies with ISO 160010.

Various sampling devices may be connected to the chamber, e.g. adsorbent tubes for volatile organic compounds or cartridges for sampling of aldehydes or organic acids. Results are emission factors in units of µg/(m²*hour).

Potential new use of the FLEC is studies of processes on surfaces such as chemical reactions, exposure and adsorption/desorption processes. A reacting gas or exposing gas is introduced in the circulating air and the emitting compounds are sampled and analyzed by suitable techniques.

Other chambers

Small home-made chambers or desiccators with inlets/outlets may also be used for exposure experiments. Examples are the following pictures.
 

• SOG-3 Ultraviolet Products

HydroAir Bath and Spa Ozonator 20-5133

up to 3 ppm @ 1 Liter/minute of air)

20 – 280 ppm at various flows and settings

Ozone monitor:

• O₃ 42M (Environnement, France)

The ozone monitor was calibrated against NIST Standard Reference Photometer at the Bureau International des Poids et Mesures (BIPM) in Paris, France.
 

Gas Chromatography:

·      Gas chromatographs (Hewlett-Packards 5890 GC) with thermal desorption (Perkin-Elmer ADT 400) and simultaneous mass selective (5972 MSD) and flame ionization detectors for determination of volatile organic compounds collected on adsorbent tubes.

·      Direct Thermal Extraction – for determination of organic content in aerosol particles collected on filters by thermal desorption /GCMS.

 Liquid Chromatography:

·      Liquid chromatograph with UV-detector (Varian 9050).

·      Liquid chromatograph with mass selective detector (Micromass Quattro Micro), electrospray inozation (ESI) or Atmospheric Pressure Chemical Ionization (APCI) operated in either positive or negative mode.

Direct gas inlet for APCI/MS.

 Aerosol physical parameters: in cooperation with Göteborg University

·      Scanning mobility particle sizer (SPMS) TSI 3936 instrument together with a TSI 3080 Electrostatic Classifier (including either TSI 3081 Long DMA or TSI 3085 nano-DMA) and a TSI 3010 Condensation Particle Counter; determination of size distributions. 

·      CPC condensation particle counter (TSI, model 8525, P-Trak). P-Trak instrument measures total number of particles > 20 nm as 1-minute averages.

 Infrared Spectroscopy:

·      Fourier Transform Infrared Spectrophotometer (Nicolet 6700) with ATR Attenuated Total Reflection investigation of surfaces – e.g. for aerosol samples collected on filters (functional groups of organic compounds).