Pumped sampling of in-vehicle air
|Formaldehyde monitoring || |
Formaldehyde is too reactive to monitor by TD–GC–MS, and must instead be sampled onto DNPH cartridges, which generate a stable derivative. These cartridges are then analysed by high-performance liquid chromatography (HPLC). More on formaldehyde monitoring.
This is carried out in a three-stage test in accordance with ISO 12219-1 (Specification and method for the determination of volatile organic compounds in car interiors) using pumped sampling of cabin air onto sorbent-packed TD tubes, with analysis of the tubes by GC–MS in the usual manner. The three stages are:
- Sampling of VOCs and carbonyl compounds under simulated ambient conditions (‘ambient mode’) at 23°C, with no air exchange.
- Measurement of formaldehyde at elevated temperatures (‘parking mode’).
- Sampling of VOCs and carbonyl compounds after simulation of the vehicle being parked in the sun, i.e. at elevated temperatures (‘driving mode’).
These tests allow car manufacturers to obtain a full understanding of the overall VOC profile that might be experienced by an occupant of the vehicle.
- For discussion of the application of thermal desorption to the monitoring of vehicle cabin air, see Application Notes 028 and 033.
- For a more in-depth discussion of standard methods relevant to in-vehicle air, see: M. Wensing, Standard test methods for the determination of VOCs and SVOCs in automobile interiors, in: Organic Indoor Air Pollutants, ed. T. Salthammer and E. Uhde, Wiley-VCH, 2009, pp. 147–161.
The following pages may also be of interest: