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Instruments which can provide teeth to the new environmental


Instruments which can provide teeth to the new environmental

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									MIT 28/04/2004 13:40 Page 1


Instruments which can provide teeth to the new environmental control legislation
by Maurice McDowell, MIT
The soon to be introduced amendment to the National Environmental Amendment Act will result in much stricter control of our environment through the introduction of environmental management inspectors (EMIs) who will have powers to ensure that atmospheric and water pollution is kept within acceptable limits. In other countries strict laws regarding pollution have been in place for many years and that has resulted in the development by the US company Inficon of a number of portable systems for the identification and monitoring of toxic industrial chemicals (and chemical warfare agents) in air, water and soil.
In terms of identification of volatile organic compounds (VOCs), Inficon has developed the HAPSITE Chemical Identification System which is a man portable gas chromatograph/mass spectrometer (GC/MS). The HAPSITE allows on-scene detection, HAPSITE is that the analysis is carried out at the site. Traditional methods of collecting air in canisters or bags for later laboratory analysis can result in sample loss for example in the case of reactive sulphur compounds (found in emissions from refineries and the paper and pulp industry for example). The sample collection device can also act as a media for other chemical reactions that will alter the makeup of the sample before laboratory analysis. For water analysis the HAPSITE can be fitted with the unique SituProbe Purge and Trap system whereby water can be sampled for the presence of VOCs without exposing the delicate parts of the instrument such as pumps, valves and cells to the water matrix. This instrument is widely used for water source protection, storm water monitoring, groundwater remediation as well as emergency response. Where soil has to be tested a portable Headspace Sampling System is designed to withstand offered and samples harsh conditions, is are loaded into weather resistant and glass vials, placed is easily deconin an oven, and taminated itself after heated to a preexposure to hazardous selected tempcompounds. The total erature. Following weight is 16 kg and it equilibrium the is easily carried on the headspace in the person’s back or over vial is flushed with Portability of the Scentograph a shoulder. Besides a VOC-free carrier coping with the full gas and drawn into range of TICs the HAPSITE will detect the HAPSITE GC/MS, where any VOCs are chemical warfare agents (including Vx, Sarin identified and quantitatively measured. etc.) and has been used to investigate odour The HAPSITE is also widely used by the complaints and sick building syndromes. One military and has been deployed by both UK of the major advantages of using the and US forces in Afghanistan and Iraq, mainly HAPSITE can be used to identify the problem gas (two-tanker crashes have occurred in America resulting in the formation of unknown toxic compounds) and to monitor the area after clean up to ensure that decontamination is complete. The HAPSITE has been

HAPSITE with head sampling unit
identification and quantification of chemicals in the air using a built in mass spectral library provided by the National Institute of Standards and Technology (NIST). The instrument has an onboard Intel Pentium computer with a 2 Gb hard disk while a builtin GPS system allows the instrument to record the exact position of the sampling location along with the field data and a date/time stamp. In North America and other countries this provides legally defensible data for civil or criminal court cases. In addition to its use for environmental sampling, the HAPSITE has been found to be invaluable to first responders in the case of accidental chemical spillage resulting in accidents to rail or road tankers. Here the


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in the search for chemical warfare agents. It has also been used by civil defence authorities and the police to provide warning of possible chemical attacks at major events such as the Olympics. Years of field use by environmental agencies, military units, HAZMAT response teams, stack testing companies and environmental and industrial hygiene professionals has proven the reliability of the HAPSITE and the benefits of field analysis. The US Environmental Protection Agency (EPA) evaluated the HAPSITE during 1998 and concluded that the equipment “could be employed in a variety of applications, ranging from producing rapid analytical results for screening investigations, to producing accurate and precise data that are directly comparable to that obtained from an off-site laboratory.” Monitoring for known air or water pollutants (such as methanol in used water at paper and pulp plants, THMs in drinking water and sulphurous compounds emitted

chemical warfare agents can be accurately measured and reported in minutes in the field. The portable and flexible design of the CMS200 makes the unit easy to move from one location to the next to perform spot analyses or multiple on-line analyses. The SituProbe, as used with the HAPSITE prevents pumps, valves and cells from being exposed to the water matrix. The top of the range CMS500 was designed with water utilities in mind and is a fixed unit which provides continuous online monitoring of VOCs and TICs in drinking water or effluent recycling plants. In the case of GC systems the unit must be calibrated by introducing a sample of a known calibration mixture which can contain up to 30 compounds. The Scentograph then performs a chromatographic analysis of this sample and displays the calibration chromatogram including the name, concentration level and retention time of each of these compounds. The area under each peak is integrated and the concentration level

monitoring. The main conclusions were that the system reproduces laboratory results within 96% on the average. The precision of the Scentograph was found to be 8% compared to 7% for the laboratory while the accuracy was 10% compared to 7% for the laboratory. The conclusion of the report was “The instrument can be deployed in a variety of applications, ranging from producing rapid

HAPSITE being used to detect pollutants in water

HAPSITE being used in an emergency situation
by refineries) is much easier and Inficon offers a range of portable and fixed Gas Chromatograph (GC) systems for this. At the lower end of the range is the Scentograph CMS100 air analysis and monitoring system which is used in conjunction with a laptop and can measure concentrations to the partsper-trillion level. A detachable laptop with user-friendly software is used to control the system operation, conduct the sample analysis and store the results. While the system will meet the requirements of any chemist it can be easily operated by less experienced personnel. Realtime remote operation is possible through the addition of an optional modem and software. The Scentograph CMS200 is a portable air and water analysis and monitoring system where concentrations of VOCs, TICs and

analytical results in screening investigations to producing accurate and precise data that are directly comparable with that obtained from an off-site laboratory. This data could be used to develop risk assessment information, support redemption process and fulfil monitoring requirements.” In conclusion, the HAPSITE and Scentograph product range allows detection and monitoring of concentration levels of hazardous VOCs in the field, be they present in the air, soil or water. Virtually instantaneous results allow for immediate remedial action by the polluter and would ensure that the environmental management inspectors can take immediate action without the delays associated with normal laborator y testing.

of the standard is assigned to this peak area. Compounds detected during monitoring which do not match compounds identified during calibration are listed as unknown. These unknown Scentograph 100 being used for air monitoring compounds may be identified by computerised methods where the sample analysis ECM – Tel: 012 329 4116 results compare with other calibration results stored in the memory of the computer or by scanning various compound libraries where hundreds of compounds are listed. MIT – Tel: 012 348 0569 The EPA has also evaluated the Scentograph in terms of on-site water


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