| EnviroGulf Consulting | ![]() |
|---|---|---|
ENVIRONMENTAL CONSULTANTS | ||
A Links Group Company |
QUALITY CONTROL & ASSURANCE |
EnviroGulf Consulting (EGC) operates a Quality Assurance Plan which is essential for producing valid field and laboratory data for environmental monitoring programs and assessments of contamination. High quality analytical data are needed especially in those programs and assessments where trace element concentrations are at or near the detection levels of the analytical methods used.
EGC's commitment to this plan assures a high quality technical product to our clients.
The following sections summarise the measures and procedures taken by EGC to ensure the high quality analytical results to our clients.
EGC's Quality Assurance services include:
All subcontracted analytical laboratories are registered with international or national authorities for testing and analysis or are in the process of undergoing registration.
EGC maintains strict chain-of-custody control over samples, from the time of collection until logging in at the receiving laboratory, thus assuring the integrity of samples, data recording and reporting.
Once samples are logged into subcontracted laboratories, chain-of-custody becomes the responsibility of the engaged laboratory and under the direct control of the laboratory manager and responsible chemist. EGC maintains close liaison with laboratory managers and monitors analytical progress.
After analysis, clients' samples and, or, unanalysed fractions or extracts are stored for future retrieval. Normally, our clients samples are stored until such times as the client wishes to terminate this facility or a project has been completed and environmental approvals received.
Most analytical methods used at our subcontracted laboratories are clearly referenced, and are either identical, or very similar, to methods promulgated by standard-setting organisations such as the US EPA, APHA (Standard Methods) or the British Standards Institution (BSI). Any modifications to these methods such as changes in scale, apparatus, or concentrations are recorded and notified by the engaged laboratory.
Control of precision is achieved by within-run duplicates of samples which are generally run at a frequency of 10% by our subcontracted laboratories.
Subcontracted laboratories use standard reference materials (SRMs) whenever possible as a check on the accuracy of each analytical run.
In methods where digestion and extractions are required, recovery checks (spiking) are used to estimate the efficiency of the analysis. Results are expressed as percentage recovery, and sample recoveries outside the range 85-115% are deemed unacceptable and appropriate corrective action is taken.
In general, most laboratories traditionally report detection limits which are based on a signal-to-noise ratio of 2.5. Current practice also includes statistically determined detection limits based on the standard deviation of within-run replicates in accordance with US EPA and APHA recommended calculation procedures.
EGC can advise clients on the levels of detection required for environmental sample analyses.
Considerable cost savings can be achieved where low detection limits are not warranted nor required by the regulatory authorities.
EGC maintains close contact with subcontracted laboratory managers. Problems arising from sample delivery, treatment and analysis are routinely solved in an expeditious and cost-effective manner.
Subconsultants to EGC are also instructed in the proper labelling, handling, storage and shipment of samples to receiving laboratories. Pertinent attention is paid to the appropriate customs and quarantine regulations, where these apply to the importation of biological or hazardous sample types.
Finally, confidentiality is strictly enforced on all our clients' data. Sample coding provides individual identification codes, such that subcontracted laboratories need only know the type of environmental sample to be analysed without knowing its source.