For many years the water industry has relied on traditional sampling techniques to monitor water quality in a wide range of environments. Traditional tests such as BOD, PH, Dissolved Oxygen and Ammonia have formed the bedrock of monitoring parameters. There are however other ways to establish water quality and UV fluorescence offers an up to date solution for the investigation of Organic pollutants.
UV Fluorescence works by using a light source to excite a water sample and cause certain compounds in the water to fluoresce. This fluorescence is then measured using a detector and filter which eliminates the excitation wavelength and passes the wavelength of the fluorescent material. The technique of course relies on the water sample having a fluorescent constituent and there are only a limited number of fluorescent compounds which are useful in determining water quality.
Until recently the biggest issue facing the use of this technology has been the size and cost of the available equipment, usually such measurements are carried out on large bench top spectrometers costing in excess of £25k and often weighing over 20kg’s. This alone is a significant barrier to the widespread use of fluorescence in routine monitoring but coupled to this is the requirement for such bench top instruments to be operated by a skilled technician and of course their associated costs.
The advent of smaller but equally sensitive detectors and the ability to produce small but very powerful light sources utilising either LED or Xenon lamp technology has now brought a portable solution to this problem.
Currently operators have to make visits to a site in order to collect samples, log and send them in a prescribed format and under regulated conditions to the lab, wait for the samples to be processed and then collate the data generated into a usable format. The benefits to such a regime are that there is an on-going record and audit trail which can be used for evidence, however the overriding cost implication born by the water companies far outweighs these simple markers. Man hours for the operator, vehicle costs, equipment costs, consumables, lab overheads, lab staff, data collection and analysis all contribute to the real cost of monitoring.
The advantage therefore of taking the measurement in the field, getting an instant answer and being able to act immediately on that evidence massively reduces the cost overheads associated with such sampling regimes.