Passive sampling to adsorbent tubes is an easy and cost-efficient method that gives average VOC concentration during the sampling period. Recommended sampling period varies with assumed concentration in the sample, from 8 hours to weeks. Our clients use this method for workplace, indoor and outdoor sampling, on offshore platforms and in saturation diving systems. VOC is analysed with thermal desorption and gas chromatography-mass spectrometry.
Passive sampling is a recognised method in normal atmosphere, and NUI has further developed the passive sampling to be used also in hyperbaric atmospheres, such as in saturation diving chambers.
Passive sampling and subsequent VOC analysis can be used to monitor the following:
Pressurised air/gas quality
Pressurized cylinder samples offers large sample volumes, which is needed for multiple analyses. Compressed air samples or saturation diving atmosphere samples make up the majority of our pressurized cylinder samples. Our cylinders have electroplated inner surfaces, and are equipped with valves in both ends. Maximum sample pressure is 60 bar.
Analyses from pressurized cylinder samples include: