P S Analytical specialise in the manufacture and support of instrumentation which is used for the ultra-low level detection and measurement of mercury, arsenic, selenium, antimony, tellurium and bismuth in all matrices.

P S Analytical (PSA), a company with a turnover of over 7 million GBP, has gained an international reputation as leaders in the determination of these environmentally important elements. Matrices include water, soils, sludges,
effluents and gases, with customers and installations worldwide.

Peter Stockwell

Founded in 1983 by the company’s managing director and co-owner Professor Peter B. Stockwell, the company soon utilised the atomic fluorescence technique to produce the first analyser, the Merlin Plus system, which gave analysts the ability to measure mercury at levels of below 1 ppt at up to 120 samples per hour. This was rapidly followed by the successful extension of atomic fluorescence to the ultra–low measurement of the hydride forming elements, notably arsenic, selenium, antimony and tellurium.

The current instruments have the vapour generation and the atomic fluorescence detection integrated into a single unit for maximum sensitivity. They can also be linked to separation techniques to provide speciation profiles of the elements in the sample matrix.

PSA has now extended the range of analytical instruments to cover online instrumentation which can measure mercury in fossil fuels, notably coal fired stack emissions and natural gas plants. The systems provide both measurement and control facilities which include a calibration system traceable to NIST standards. This means that the instrument can be regularly checked and in addition, the integrity of the sample can be validated easily.

More than 50 online systems to monitor and control have now been installed around the world to measure the mercury levels in natural gas, including liquefied natural gas applications. These systems are operating on a continuous basis and ensure the safe running of the plants. For these applications PSA provides the complete solution from sampling through to measurement and reporting. Our online systems carry IECEx certification which is becoming a necessary standard for installations in potentially explosive atmospheres.
The PSA offline sampling system is combined with the Sir Galahad instrument which conforms to the ISO 6978 and ASTM 6350 methods and is considered the industry standard for mercury measurements in natural gas streams.

In 2007 PSA’s quality management systems and procedures achieved the recognised standard requirement for quality; ISO 9001:2000. After continuing review and improvement in 2009 PSA was awarded ISO 9001:2008 in recognition of our achievements in design, manufacture, testing, installation and support.

PSA has built up firm ties with universities in the UK, Europe and America and has collaborated with industrial companies and environmental agencies developing solutions to difficult analytical problems.

Since 1995 PSA has offered industrial placements to students studying chemistry and information technology. More than 40 students have taken advantage of this facility and many of PSA’s present staff of 35 have been recruited following their graduation.
There is increased global concern about pollution in the environment and the levels of pollution to which animal and plant life is exposed, particularly the heavy metals such as mercury, arsenic, selenium and antimony.

The PSA Laboratory and R & D Team

Regulatory limits are set (or are being set) for all of the above, of which mercury is the most frequently encountered problem. Since the various compounds of mercury differ widely in toxicity beginning in 2009 PSA has offered mercury speciation systems to highlight the real problems of mercury contamination. The company is committed to improving all of its products through customer feedback, subscriber communities and a continuous programme of development.
PSA provides systems which not only meet the regulatory levels but also provides the level of sensitivity capable of meeting future demands.

Production of all PSA systems takes place at our modern, purpose-built facilities in the UK, allowing manufacture to the highest standards of quality. All regulatory requirements are observed and met before any product is shipped. Sales are made by the PSA sales team and through a fully trained and monitored global network of representatives.

In September 2002 PSA established itself in the USA setting up P S Analytical Inc at offices in Deerfield Beach, Florida, enabling PSA to better serve the expanding US marketplace.