Portable FTIR verifies safe working environment

04 December 2009

One of the world's largest pharmaceutical companies has employed a portable FTIR multiparameter gas analyser from Quantitech to check air quality in an office for which there had been a number of odour complaints. Monitoring up to 25 compounds simultaneously, the FTIR was able to demonstrate compliance with occupational safety limits.

Many gases are odourless, however, it is important to investigate odour complaints because they might be indicative of a potential safety problem, so it is often necessary to conduct air analysis to ensure that levels are below those specified in the EH40/2005 updated 2007 Workplace exposure limits. In addition to workplace exposure limits (WELs), odour thresholds (OTs) are issued by the World Health Organisation and others, and these can be used to assess the likely source of an odour problem.

A Gasmet DX 4030 was employed to assess the office air by sampling and analysis for a period of approximately one hour. The results provided a comprehensive picture of the room's air quality, demonstrating that there were no reasons for concern from a safety perspective.
In addition to gas analysis of the room air, samples were taken from potential sources of contamination – carpet, radiator vent, skirting boards, whiteboard cleaner and marker pens.

However, whilst elevated levels of compounds such as Dichloromethane, Dichloroethane and Limonene were observed when a marker pen and cleaner were tested, the levels did not exceed the WELs for these substances. Interestingly, however, OTs were exceeded for Limonene and Methylcyclopentane.

The FTIR gas analysis demonstrated that the air in the room was safe to breathe. However, it did not identify the source of the odour complaints. It is likely therefore that the source produces compounds with extremely low OTs – probably parts per trillion.

Quantitech's Dr Andrew Hobson, who carried out the test in order to demonstrate the capability of portable FTIR, said: "Traditionally, one of the challenges for workplace monitoring has been to test for every gas that might be a problem. Generally speaking, it is necessary to guess which gases are most likely to be present and select the appropriate monitoring technology accordingly."

"The great news is that the new portable FTIR (Gasmet DX4030) generates a complete infrared spectrum of the air which can be interrogated after sampling to identify hundreds of compounds, thereby substantially reducing the risk of failing to identify a significant compound