At Igne we offer a wide range of tests to meet the needs of our clients, from routine water quality testing to more complex analyses of contaminated land and hazardous materials.
About
Our team of experienced chemists are experts in their field and use the latest technology to provide our clients with accurate and reliable results. We are also accredited by the United Kingdom Accreditation Service (UKAS), which means that our results are accepted by regulators and other authorities.
Igne’s chemical testing division at a glance:
Work
Work we undertake includes:
The work we do for clients is equally as diverse: e.g., we are supporting Balfour Beatty with the HS2 infrastructure project in and around the Birmingham area, enabling them to remediate the land they are working on or assess the quality of the topsoil they are importing for example.
We also work with the National Science Museum Group which includes the Victoria & Albert Museum in London, the National Railway Museum in York and the National museum of Film and Photography in Bradford!
Whenever the museums move an artefact that contains oil of any kind, the oil must be tested for Polychlorobiphenyl (PCB) content for health and safety reasons. These compounds are carcinogenic and were banned many years ago.
If you need chemical testing, Igne will be your trusted partner.
Stages
The stages of chemical testing at Igne – at a glance:
In Depth
Once a quotation has been accepted and the programme of works agreed with our clients, we provide the correct containers for them to put samples in to. If our own containers aren’t used, we cannot vouch for the sample integrity when it’s received in the lab and as such, that could mean the analysis might be compromised – the sample may be classed as deviating.
Collection
Plastic containers are the container of choice due to their durability – these are used where inorganic parameters are to be tested for. Many organic compounds however, can interact with plastics and adhere to the inside of a plastic container, or conversely, the organic compounds within the plastic may leach into the sample itself. In addition, many organic compounds degrade in UV light. For this reason, amber glass bottles are used when testing for organic compounds.
At Igne we have done lots of work in reducing the amount of a sample required to perform testing which is particularly useful where sample availability is restricted. It can also save our clients time and money.
Unlike many other labs, our holding times and sample integrity data have been developed without the addition of preservatives to our sampling bottles, again reducing effort on site and reducing the health and safety risk in handling preservatives.
When samples are submitted to us, it’s important that we get the right instructions and information from our clients so we get things right from the start. This is our Chain of Custody (CoC) document that we ask all clients to complete when submitting samples to us. It asks for data including client contact details, sample IDs, testing requirements, specific hazards and turnaround time requirements
The information from this document is then transferred to our Laboratory Information Management System (LIMS).
At Igne, we routinely carry out over 100 different tests in the lab, on an extremely variable range of matrices. Each of our methods has to be validated or proven to work; accuracy, precision, variability and recovery all have to be considered. Each method and the processes within it are documented and referenced with published standards such as BS1377, Blue Book and USEPA guidance.
We currently carry out around 5,000 tests, producing 100,000 pieces of data per week.
Upon receipt in the lab, a sample’s details are checked against the requirements on the CoC and the samples are booked in to LIMS. At this stage a sample receipt is sent out to our clients to demonstrate we have received the samples and to illustrate our interpretation of their instructions. This allows the client the opportunity to modify if necessary.
Samples are given a unique laboratory identification number and barcode that stays with the sample as it travels through the lab. Many of the analytes we test for are labile, they easily break down or degrade, so time is now of the essence.
Preparation
99% of the analysis we perform in the laboratory is done on a modified form of the received sample.
Usually this means the sample has to undergo some form of preparation, then extraction or digestion to enable the analytes of interest to be presented to our instrumentation in a liquid form.
Consequently, the primary preparation steps for solid matrices might involve the drying and grinding of soil to form a homogeneous mix. The 24hour leaching process is also started (2:1, 8:1 or 10:1 WAC variants).
Air dried and ground or as received soils are weighed out into aliquots for further preparation steps down stream and water samples might be filtered through a 0.45um filter for dissolved analysis.
Organic
There are two basic distinctions of testing within our chemistry lab. The first distinction is the testing of samples for organic compounds, i.e., those that contain carbon and carbon - hydrogen bonds – examples being petroleum hydrocarbons, diesels, pesticides, poly-aromatic hydrocarbons, PCBs etc.
Generally speaking, samples are mixed with an organic solvent such as acetone, hexane, or dichloromethane which serves to extract the analytes of interest from the sample and into the solvent.
The solvent containing the analyte of interest can then be cleaned up to remove interferences if necessary and concentrated to a small volume which is then presented to an instrument for analysis.
Inorganic
The second distinction is the testing of samples for inorganic parameters, compounds or elements that don’t contain carbon.
Examples are metal, cyanides, nutrient parameters such as ammonia, nitrate, nitrite, chloride and so on. Here, samples are usually digested, and analytes extracted with an acid, an alkali or just water.
We use a digi block digester to digest soil samples for subsequent metals analysis. It’s essentially a high-pressure heating block. Aqua regia, a mixture of 3 parts hydrochloric acid to 1 part nitric acid is used to completely digest the soil. This extremely strong and robust mixture of acid is so called ‘kings water’ (aqua regia in Latin) as it is the only combination of acids to thoroughly digest gold!
Once the samples have been digested, they can be presented to an instrument for analysis
Analysis
Our GC-MS machines are used to study liquid, gaseous or solid samples.
A sample is injected into the GC-MS column (which sits at a high temperature) where it is carried by helium gas and over a period of minutes, the various portions of the sample are separated out on the column. Each component, due to its size, polarity and mass/charge is retained on the column for a specific length of time. Once it elutes from the column, it is detected by a detector (mass spectrometer detector in this instance).
The system is calibrated using standards of known concentration which allows the ‘unknown’ samples to be quantified. In our inorganic example of metals testing, the equipment used here is an inductively coupled plasma, optical emission spectrometer.
Here a sample is pumped in to a device called a nebuliser where it meets a stream of argon gas (again argon is inert) creating a fine aerosol. When introduced to a high level radio frequency, argon forms a highly ionised plasma – this plasma is hotter than the surface of the sun (6000 degrees kelvin).
In passing into the plasma, the metal ions within the sample are excited and move up an energy level, falling back down almost immediately. The difference in energy is given off as light. In much the same way as fireworks contain different metallic salts, each metal has its own characteristic colour of light emitted.
This characteristic colour or wavelength of light is what is detected by this instrument’s optics. Again, quantification is achieved by firstly calibrating the instrument with known standards.
Many of our instruments are automated at Igne. They are able to perform multiple different analyses simultaneously – typically an ICPOES machine for example can detect around 30 or so different metals in a sample in around 1 minute.
Not only are they able to differentiate between many different types of similar analytes but they are supersensitive too. Some can detect chemicals in concentrations as low as 1 part per trillion (1 with 12 noughts – a million million) or one drop of water in 20 Olympic size swimming pools. Or they are 1000 times more sensitive than a shark’s sense of smell.
Other types of instruments routinely used include spectrophotometers and colorimetric devices such as the smartchem and sKalar instruments. These automated systems are used to detect analytes such as ammonia, nitrates, nitrites in the case of the smartchem, and cyanides and phenols for the sKalar.
Such instruments work on the basis that when specific reagents are mixed with the analyte of interest, a chemical reaction occurs which causes a colour change. This characteristic colour change is measured using a spectrophotometer.
Other techniques are too numerous to mention but include Polarised Light Microscopy for asbestos analysis, selective ion probes for pH and conductivity and gravimetric analysis for suspended solids and loss on ignition.
Instrumentation
Before an instrument is first ever used, it has to be validated, i.e., proven to be working correctly. Usually carried out over 11 discrete days, this is a rigorous set of tests it must undergo to determine precision and bias characteristics, specificity (the ability to differentiate between compounds) and sensitivity. Once validated, and signed off, an instrument can be put into routine use.
However, each time it is used, it must undergo a series of system suitability checks to prove it is still compliant and fit for purpose. This is similar to a car having an MOT each time you get in to drive it! Each instrument is also calibrated before use. Here, certified materials of known concentration and make up are analysed by the instrument and the system response determined. A calibration plot of instrument response vs concentration is constructed. The response of the unknown samples is plotted on this calibration curve and the corresponding concentration of analyte deduced.
The quality of our data at Igne is of vital importance for obvious reasons – in many circumstances our clients are making potentially life changing decisions based on it
Accreditation
For the highest level of quality in environmental laboratories, the Monitoring Certification Scheme (MCERTS), it’s imperative that the lab demonstrates continuing precision and accuracy within certain limits. For definition, precision is the ability to get the same result over and over again – repeatability. Accuracy is the ability to achieve the correct result.
It’s possible to be precise but not accurate, and to be accurate but not precise. We are both and maintain MCERTS accreditation. Our MCERTS accreditation status is supported by our accreditation to the ISO17025 standard. Each year we are audited against the standard by the United Kingdom Accreditation Service (UKAS). We have held this accreditation since the early 1990s and it is seen as a ‘must have’ badge of quality in our industry.
Part of this accreditation means that we must routinely analyse certified standards of known concentration – Analytical Quality Controls (AQCs) through our methods. These comprise samples that pass through the preparations stages of each process (Process AQCs) and those that pass through the analytical parts only (Instrument AQCs). So much so that 20% of the samples we analyse are AQCs.
The results for each AQC are plotted on a graph called a Shewhart chart. Results are controlled statistically through normal distribution rules and AQC results should be within plus or minus 3 standard deviations of the mean result to pass.
Only if an AQC passes are the associated batch sample results reported. Should an AQC fail for any reason, this non-conformance is investigated, corrective and preventative action derived and the samples the associated client samples reprepared and re analysed. Statistically, at least 3 in every 1000 AQC results will fail.
The quality control measures we have spoken about already are internal quality controls. We also regularly participate in external quality control, round robin or proficiency testing schemes. As part of our ongoing accreditation, we subscribe for third parties to send us samples that they and they alone know the make-up of. We prepare and analyse the samples ‘blind’ and submit the data back to the third party organisation. The third party (RTC, Contest, LEAP for example) assesses our data and publishes (anonymously) the data.
An average pass rate of 80% compliance is considered good. Our average pass rate at Igne is >90%.
Once all analysis is completed and all AQC checks have passed, the sample data is transferred electronically to our Laboratory Management System or LIMS. LIMS is the life blood of our lab, encompassing many functions from quotation building sample tracking.
Once again, the data is checked, this time for the relationships between different data sets – for example a COD result should always be higher than a BOD, and a TPH should always be higher than a PAH.
Data is then approved by a senior member of the Lab team.
The customer services team then compile a certificate of analysis report and any additional export formats that are required such as a WAC report, AGS file or very soon a Haz Waste on-line report
The last and in many ways most important link in the lab process chain is the customer services team. This team of dedicated Project Managers manage everything from sample receipt, to managing progress through the lab, report production, KPI generation, invoicing and the handling of queries. As they are client facing, our aim is to be friendly, supportive and attentive with a desire to exceed our clients’ expectations.
Here is a list of some of the specialist chemical tests that we offer:
Chemical testing of cement content - mortar designation - initial consumption of lime.
Chemical testing of cement content, mortar designation, and initial consumption of lime is a process used to assess the quality and properties of mortar.
Mortar is a mixture of cement, sand, and water that is used to bind bricks and other masonry units together.
Cement content is the amount of cement in a mortar mix. It is important to have the correct cement content in order to produce a mortar that is strong and durable.
Mortar designation is a system of classifying mortars based on their strength and properties. Mortar designations are typically given in the form of a ratio, such as 1:1:6 (cement:lime:sand).
Initial consumption of lime is the amount of lime that is added to a mortar mix to improve its workability and plasticity. Lime is a soft, white powder that is made from limestone.
Chemical testing of mortar is carried out by our laboratory at Igne. We will test the mortar for its cement content, mortar designation, and initial consumption of lime.
The results of the chemical testing can be used to:
Here are some specific examples of chemical tests that can be performed on mortar:
Chemical testing of mortar is an important tool for ensuring the quality and durability of masonry structures.
For more information regarding any of our Specialist Chemical Testing Services, contact Igne today
Email: hello@igne.comCall: 0371 789 1000
