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Laboratory water

A key reagent forexperimental success

Contents
Introduction•What’s in your laboratory water?

•

Why should you worry about water impurities?

•What water quality do you need – and for what?

•

Getting a reliable supply of laboratory water•

Choosing an in-house water purification system•Why choose ELGA?

•Working with ELGA•

References
Get in touchIntroduction
Every day, scientists around the world are using water for a multitude of purposes. But
the quality of this reagent is too important to ignore - contaminants and variabilities inlaboratory water are putting too many results at risk.
In this guide, we share ELGA’s expert knowledge about laboratory water, which wehave gained since the 1950's from our pioneering development in water purification
technologies. We explore the different levels of water purity and look at some of thechallenges around choosing what to use for a successful experimental outcome at themost economical cost. And we discuss the different options available for achieving a
reliable source of purified water in your laboratory.
We will demonstrate why using the right level of water purity is an essential way tohelp you achieve more consistent, accurate results. And that installing an inhouse purification system can save you time, money and reduce your environmental
impact.

 What’s in your laboratory water?
Water is essential for our everyday lives. We drink it. We wash in it. We clean with it.
As we know, life on Earth is dependent on it.
And water is used for a myriad of purposes in laboratories all over the world. In fact, a typicallaboratory is estimated to use around five-times as much water as a comparably sized officeblock – that’s about 35 million litres per year .1
But how much do you really know about the water you’re using for your experiments?
Two important factors you need to be aware of are:

• Water contains a myriad of contaminants

Due to its incredible solvent properties, water mixes with and dissolves a wide variety of substances -meaning
lab water sources contain many different contaminants (see Table 1). Even trace levels of impurities can affecta variety of scientific applications2 – putting your results at risk.

• Water sources are highly variable

Drinking water needs to conform to local regulations and have acceptable clarity, taste and odor. This isachieved by treating natural water sources, such as reservoirs, rivers or underground aquifers through a seriesof steps, which vary with the water source, local and national regulations, and the choice of technologies.3 So,
it’s easy to appreciate that water will vary significantly from one geographical location to another - and it caneven change from season to season.4 Water is a source of variability in your experiments that you can’t afford
to ignore.

Contaminant

Examples of problems or detrimental effects on laboratory applications

Suspended particles andcolloids

Inaccurate or poor results from most laboratory assays and methodologies

Dissolved inorganic
compounds

Ionic instability will affect protein solubility and protein-protein and protein-lipid
interactions – which can affect enzymatic reactions

Block filters, chromatography columns or membranes

Heavy metals are toxic to various cells in cell culture
Dissolved organic
compounds

Can support growth of unwanted microorganisms
Poor results from sensitive processes such as chromatography
Can degrade other experimental targets e.g. proteins and nucleic acids
Can interfere with spectrophotometric testing
Deactivates enzymatic reactions and inhibits cell growth in cultures

Microorganisms &biomolecules (including
endotoxins, enzymes andnuleases)

Failure of techniques requiring sterile conditions

Dissolved gases

Oxygen and nitrogen in water can affect biochemical reaction rates. High concentrations
can even result in bubble formation, disrupting spectrophotometric measurements and
impeding flow through micro-channels and columns.

Poor results from molecular biology techniques
Blocking filters and tubing

Chlorine can bleach immunohistochemistry staining on slides

Table 1: Water contaminants and examples of their potential impact on laboratory applications.2

 Why should you worry about water impurities?
As a scientist, we know that you care about getting reliable, accurate results from yourexperiments. And, as you will be all too aware, producing good data from your experiments ishighly dependent on the quality of your reagents.

It’s simple. Poor reagents in = poor results out
You wouldn’t dream of cutting costs using a sub-standard enzyme or chemical reagent - it’s just not worth thewasted time and frustration of failed experiments or unreproducible results. And it’s no different with laboratorywater, that frequently-used substance that underpins so many scientific and medical applications. Making surethat you use the correct level of water purity is an easy step towards producing consistent, accurate results.

Did you know?

• Contaminants or ionic imbalanc es in your laboratory water
can seriously impact on your data

• Water impurities can affect most enzymatic reactions needed
for basic molecular biology techniques• Storing purified water will introduce leachables into the waterand encourage proliferation of bacteria

Here are just a few examples of how water impurities could affectvarious experimental techniques:
Blotting techniques• Your success with Southern, Northern or Western blotting will depend upon the water quality you use forpreparing your samples and solutions. For example, bacterial contamination could introduce additional
proteins that can compromise Western blotting. Bacterial nucleases can degrade nucleic acids during
Northern and Southern blotting – and stray organic molecules can interfere with hybridization by binding
non-specifically in place of DNA or RNA. And excessively high ionic contamination can disrupt migration
during electrophoresis.

Trace analysis• A high level of water purity is essential for these highly sensitive analytical techniques such as LC-MS, GC-MSand GFAAS. For example, performing inductively coupled plasma mass spectrometry (ICP-MS) demands yoursolutions to have virtually zero levels of additional elements or ions. With detection levels down into theparts per trillion (ppt), impurities can lead to artificially high sample concentrations or errors in blanks andcalibration samples, meaning the accuracy of results will be severely affected.

Figure 1. A comparison of
purified water qualities
used in HPLC. 50 ml water
concentrated on a C18
column and eluted with awater:acetonitrile gradient,
0–100% at 5%/min, flowrate 2 ml/min, with UV
detection at 254 nm.9

Figure 2. The effect of ioniccontaminants from wateron baseline used in ion
chromatography, integration
and resolution: (A) poor
water quality and (B) TypeI (18.2 MΩ-cm) water. The‘noise’ introduced aroundthe 10–15 minute mark isclearly apparent.10

Chromatography• As high-performance liquid chromatography (HPLC) is used to detect constituents of complex mixtures,

sometimes in the parts per billion (ppb) ranges, it’s unsurprising that results are highly dependent on water
purity (figure 1). Organic compounds can compete with the analyte, reducing levels retained in the column.
Other concerns include bacteria and ionic contaminants which can affect some chromatographic
separations.

• When using ion chromatography (IC), trace levels of ions can have a much more pronounced effect than with
HPLC (figure 2), and can lead to inaccurate or poor results. Dissolved gases, such as carbon dioxide, can alter
the pH of the mobile phase, which in turn can alter elution times or reduce the effective capacity of thestationary phase. Bacteria and organic compounds can also have detrimental effects – and particles andcolloids can result in elevated back pressure, affecting pumps and impacting on the integrity of the analysis.

Polymerase chain reaction• Water quality can impact on a universal molecular biology technique – the polymerase chain reaction(PCR). The reaction can be inhibited by water contaminants such as nucleases that can leave you without astable product – making nuclease-free water a must! And no-one wants to inadvertently amplify lengths ofcontaminating bacteria DNA. Inorganic contaminants also pose a risk, with DNA polymerases highly sensitive
to common cations that can disrupt substrate binding and inhibit enzymatic activity. Negatively charged
inorganic compounds can also compete with DNA at the polymerase active site, disrupting experiments.

Histology and immunohistochemistry• Water quality is often a key area to troubleshoot when immunohistochemistry (IHC) experiments are notworking. For example, bacteria can stick to tissue sections leading to artefacts in mounted samples. Bacterial
contaminants in water can also release alkaline phosphatase (AP) which can interfere with certain IHC
procedures that use AP for chromogenic detection. Metal ions can cause unwanted precipitation in staining
solutions or even interfere with antibody-antigen binding.

 What quality of water do you need - and for what?
It’s obvious that different techniques require different water purity levels. So, you don’t
need to use the same water for washing your glassware as you do for highly sensitive
analytical techniques - where even trace levels of contamination can ruin experiments.
But what limits are considered right for what applications? How is laboratory water categorised into
different grades or types?
There are several parameters used to measure various properties of water as a way of assessing its quality(Table 2). And around the world, several international boards have been established to generate consistent,
high-quality standards for laboratory water quality across all industries (Table 3). Some laboratories will also
adopt standards outlined in the European, US or Japanese Pharmacopoeia.

FactorWhat is it measuring?

Measurements

Conductivity

Provides an important, non-specific indication of thelevel of ions in the waterµS/cm (microsiemens)

Resistivity

Also provides a measure of ionic content.
Primarily used in assessment of ultrapure waterMΩ-cm (megohm)

Organic
compound levels

Total organic carbon (TOC) is used as a ‘universal
indicator’ for the presence of organic impurities

Total organic carbon (TOC) – parts per
billion carbon (ppbc)

Biologicalcontamination

Individual bacterial species and total viable cells counts

Colony forming units per millilitre (CFU/ml)

Endotoxins produced from gram-negative bacteria

Endotoxin units per millilitre (EU/ml)

Presence of
colloids

Suspended particles defined as being less than 0.5 µm
in size and may contain iron, silica, aluminiumor organic materials

Nephelometric turbidity units (NTU)
Fouling Index (FI)

Table 2: An overview of the key factors used to define water purity.

What

Who

Categories

Laboratory
applications

American Society for Testing and Materials (ASTM®)

Uses D1193-06 – four grades of water (TypeI-IV)5International Organization for Standardization (ISO®)
3696

Based on ISO 3696:1987 – three grades(Grades 1-3)6

Clinical and Laboratory Standards Institute (CLSI®) –formerly National Committee for Clinical Laboratory
Standards (NCCLS)

Previously three main types of water (TypeI-III), which have now been replaced withthe terms6:

Clinicallaboratories• Clinical Reagent Laboratory Water(CRLW)• Special Reagent Water (SRW)• Instrument Feed Water
Table 3: Some of the most commonly used international standards for defining water quality

Choosing which water type the ELGA way – it’s as easy as I, II, III
At ELGA, we understand that working out the best water purity for a variety of specificapplications can be challenging – going too far will result in unnecessary expense or not far
enough will endanger your results.
So our experts have done the hard work for you! We have created an easy-to-use system that classifies water
purity into broad types (Table 4 & 5) as well as a more detailed list of common applications and the water
purity they require (Table 6). Together, these will help you to match your application with the recommended
level of water purity quickly and effectively – giving your experiments the best chance of success at the mosteconomical cost.
Resistivity (MΩ-cm)

TOC (ppb)

Bacteria (CFU/ml)

Endotoxins (EU/ml)

Type I+

18.2

<5.0

<1.0

<0.03

Type I

>18.0

<10.0

<1.0

<0.03

Type II+

>10.0

<50.0

<10.0

N/A

Type II

>1.0

<50.0

<100

N/A

Type III>0.05<200.0<1000

N/A

Table 4: ‘Types’ of water classified by ELGA LabWater as defined by their measurable physical and chemical properties

Laboratory water
purity level

Examples of when to use it

Type I+

Goes beyond the purity requirements of Type I - use this for the most sensitive analyticaltechniques, such as ICP-MS or ion chromatography

Type I

Often referred to as ultrapure water, required for some of the most water-criticalapplications including key analytical techniques and molecular biology applications

Type II+For general laboratory applications requiring higher than standard Type II water levels of
inorganic purity
Required for clinical biochemistry techniques at CLRW standards

Type IIFor general laboratory use – including media preparation, pH solutions and buffers
Type II systems are often used as a feed to a Type I system

Type III

Non-critical work, such as glassware rinsing, water baths, autoclave and disinfector feeds,
as well as environmental chambers and plant growth rooms
Can also be used to feed Type I systems

Table 5: ‘Types’ of water classified by ELGA LabWater and examples of their uses.

TechniqueApplication sensitivity
required

Water type

Feed to still

Low

III

General - HighIII to I

General chemistry

GeneralII+

Glassware washing

General - HighIII to IMedia preparation

GeneralII

General - HighI

Steam generation

GeneralI

Bacterial cell culture

GeneralI

Clinical biochemistry

USP/EP CLSIII+Electrophoresis

High

I

Electrophysiology

GeneralI

ELISAGeneralI

Standard - HighI

Histology

GeneralI

Hydroponics

GeneralIII

Immunocyto-chemistry

High

I

Mammalian cell culture

High

I

Microbiological analysis

GeneralI

Molecular biology

High

I

General - HighI

Plant tissue culture

High

I

Radioimmuno-assay

GeneralI

General - HighII to I

Flame-AAS

General

II +

GC-MS

High

I+

GF-AAS

High

I+

HPLC

General - HighII to I

ICP-AES

General - HighII+ to I+

ICP-MS

General - HighII+ to I+

Ion chromatography

General - HighII+ to I+

Solid phase extraction

General - HighII+ to I+

Spectrophoto-metry

General - HighII+ to I+

TOC analysis

General - HighII+ to I+

Trace metal detection

General - HighI+

Water analysis

General - HighII+ to I+

Feed to ultra pure water system

Solution preparation and dilutions

Endotoxin analysis

Monoclonal antibody researchElectrochemistry

Table 6: Common Applications and their Water Types Getting a reliable supply of laboratory water
Now that we’ve established that water impurities are a threat to the reproducibility andaccuracy of your results, the good news is that it’s something that can be avoided!
Your options for how to source purified water include installing an in-house water purification system or buying
purified bottled water. Both routes will give you water of different grades, but there are many differences
between them.
Ultimately, the best choice for your laboratory will depend on your specific situation. When you’re deciding, it’s
important to consider the following questions:• How much ultrapure water will you be using every day?
• What flexibility do you need in terms of purity levels?
• What is your budget?
• How important is saving money in the long term to you?

In this section, we explore these two routes in more detail, which we hope will help you to decide on the bestsolution for your laboratory.

A. Installing an in-house water purification system
Laboratory water purification systems aim to remove impurities from drinking water without adding any newcontaminants. They achieve this through a multi-stage process, the exact choice of components and technologies
will depend on the requirements of each laboratory . The system will be designed using all or some of thefollowing stages:• Primary treatment – starting the purification process withrelatively simple pre-treatment technologies can effectively
enhance subsequent steps and keep costs down. Choice oftechnologies will depend on the characteristics of yourfeedwater.

• Storage - every system is likely to require a reservoir to store pretreated water, usually to ensure that you have enough purified
water available at peak times. Water can be stored in either arecirculating or a static system, preferably the former.

• Polishing – after primary treatment, there are different, more

complex technologies that you can use to increase water purity,each with their own advantages and disadvantages (Table 7).

There are often additional components included:• Membranes - fitted as the final purification step to remove
traces of bacteria or prevent back contamination.

• Monitors - it is important that you are sure the water you’reusing is as pure as you think it is. The best way to do this isthrough continuous measurement - ideally in real-time within-line systems built into the purification process.

Technology

What

Advantages

Restrictions

Reverse Osmosis(RO)

Uses semi-permeable membranes

Removes most types ofcontaminants to varying degrees(bacteria, colloids, dissolved
inorganics, organics and particles)

Does not remove dissolved gases

Cost effective
Relatively easy process to monitor
Requires minimal maintenance
Ion exchange (IX)

Electrodeionization(EDI)

Beds of cation and anion IX resinsthat remove ions from the waterby exchanging them for H+ and
OH- ions

IX resin beds held in an electricfield. Resins are regenerated
continuously

Mixed IX resins remove all
dissolved ionic compounds andCO2, giving a resistivity of up to
18.2 MΩ.cm ; <1ppb ioniccontamination

Resins need replacement orregeneration
Single-use resins require pretreated water
Very large surface area of IX resins
are a potential breeding ground for
microorganisms

No need to replace resins

Requires RO treated feed water

EDI beds typically are smaller andremain in service for long periods

Removal of ions is limited by size ofbeds, so will not be complete.

Chemical and electrical conditions
within system inhibit bacterial
growthNeeds to be followed by mixed IX
to remove residual ions for type 1
water

Microfiltration (MF) using
microporous screen filters

MF removes colloids, bacteria andparticulates

Filters can become blocked whensurface covered with contaminants

Ultrafiltration (UF) using
membrane filters

UF effectively removes mostcolloids, enzymes, microorganisms,
particles and endotoxins

Does not remove dissolved
inorganics or organics

Both of which are carried out
after the initial RO process

Ultraviolet(UV) light

May require good pre-treatment offeedwater to avoid contaminants
damaging membrane

Relatively inexpensive

Environmentally friendly incomparison with normal IX
Filtration

Limited production flow rates –requires either large membranesurface or temporary water storage

Exposure to UV light usually at
wavelengths of 254nm and
185nm

Efficient operation

Must be regularly sanitized and/or
replaced

Easy maintenanceUV light kills bacteria(254nm)Oxidation of organic compounds

185nm UV Needs to be followedby mixed IX to remove oxidizedorganics and CO2(185nm)Distillation

Produced by boiling water andcollecting condensed water
vapourEffectively separates the waterfrom a wide range of contaminants
and deactivates bacteria

Slow at purifying water - usually inbatches
Prolonged storage can lead to recontamination
Most effectively performed withpre-treated waterNot economical or environmentallyfriendly – requires large amountsof energy

DegassingUses a hydrophobic membrane filter
to remove gases such as carbon
dioxide and oxygen

Prevents micro bubble formation.
Removal of CO2 extends life of IX
consumables

Only partial removal of CO2

Vent filters

Microporous filters, and possibly
other media, fitted to a reservoir
to prevent contaminants fromentering the stored water

Filter removes bacteria, othermedia minimize carbon dioxide
and organic contamination

Regular replacement essential
to maintain effectiveness

Table 7: The main water purification methods and their advantages and restrictions

B. Buying bottled water
After finding out more about the potential complexities of choosing a good design for your in-house purification
system, we can appreciate it’s tempting to think that buying bottled water is a simpler alternative!
But you should also be aware that there are many misunderstandings (and full-blown myths) about using inhouse purification systems. To help you make the best decision for your laboratory, we explore and debunk someof these for you (Table 8).

Myth

Facts

In-house water
purification systems
are an expensive
optionIf you consider your lifetime costs, an in-house system can provide better long-term economy.
After the initial upfront costs, subsequent running costs are generally lower than buying bottled
water
In-house systems can be even more economical if you can share the costs of installation acrossseveral laboratories. Could you save money by installing a single unit with multiple dispensers?
Do you have a busy laboratory that uses lots of water? – an in-house system will probably meetyour demands better, and it will be quicker to start saving money compared to buying bottled
water. If your laboratory is quieter, you should consider how long you can justify leaving bottled
water sitting around risking microbial and airborne contamination before needing to re-test or
replace it.
Do you need flexibility with water purity levels? This may mean buying several different bottles
of water which are then left for long periods, which can impact on purity. But some in-house
purification systems allow easy reconfiguration depending on the purity you need
To help save you money, there are in-house purification systems available that give you clear
indications of cartridge exhaustion, meaning you can replace only when necessary
You can free up staff time – and operating costs - by choosing a system which has an autodispense function, meaning no hands-on waiting time for large volumes to be dispensed, as wellas an auto-rinse function that reduces user-maintenance when system usage is low.

Once you’ve bought asystem, you have lesschoice of purity level

There is no one-size-fits-all when it comes to choosing the best system for your laboratory.
ELGA experts can help you to choose a water purification system that is optimized to your purity
level needs, water volume requirements as well as to your feedwater quality.
They can also help identify whether a modular system is the best option, giving you theflexibility for easy reconfiguration if things change in the future

There’s rarely enoughspace to fit a water
purification system

If you’re limited for space, this can be a worry. However, large bottles of water can be big andcumbersome too and if you need several bottles of different types then they could soon takeup more space than a purpose-built purification system
Some modular systems provide flexible location options. Systems can be configured in a waythat fits best – with components wall-mounted, stacked or even physically separated andconnected. And if required, storage reservoirs can be put into unfrequented spaces

It’s difficult to ensure
purity on an ongoingbasis with in-housesystems

With proper maintenance, regular replacement of consumables and automated sanitization,a properly designed water purification system can give you consistently pure water for years
For peace of mind, real-time purity indicators make it easy to check on your system at any
point – and can also provide an option to download water purity data
If you’re storing purified water in a reservoir, there are extra things you can use to protect it:• Point of use (POU) filters• Recirculation at the POU and auto-rinse system to avert standing water• Vent filtration, a hygienic overflow system and a self-draining base also help protect entry
pointsBottled water also requires regular testing to ensure it has not become contaminatedIn-house systems
are often difficult to
operate and maintain

Modern systems are easy-to-use and maintain. Some systems can even give advanced warningfor cartridge replacement
Systems are available that display purity status on the dispenser. Alarms can also alert to any
major problems
Choosing a supplier with a reliable global service network ready to help you with any problems
is also a good idea

Buying bottled
water is moreenvironmentallyfriendly

There are hidden environmental effects from bottled water:• A significant carbon footprint from transportation to laboratories around the world• An environmental impact of plastic waste, which poses a huge threat to our marine
ecosystems. One bioscience department estimated they generated around
267 tonnes of plastic waste in just one year – which they scaled up toquate to around 5.5 million tonnes from labs worldwide, roughly the combined
weight of 67 cruise liners8
Whereas, modern in-house systems often employ innovative solutions to reduce energy
consumption. Technology is used to maximize efficiency and prevent waste, e.g. the ability toselect a lower level of water purity for less sensitive applications.
You can also take steps to reduce consumable use by your in-house system, e.g. not changing
cartridges until they’re exhausted.

In-house purification
systems aren’t reliable
enoughIn-house systems are often more reliable than putting your faith in external suppliers to provide
bottled water on time and to specification. Some systems offer specific features to enhancereliability and give you extra peace-of-mind, such as auto-rinse to prevent contamination, realtime TOC monitoring and notification systems to change purification packs.
If necessary, you can always run systems in parallel to make sure you have a guaranteed sourceof pure water no matter what

Using specialized
bottled water is betterfor sensitive analyticaltechniques

Commercially available bottled HPLC grade water, when used as an eluent can givesignificantly inferior results to water purified using an in-house system9
Once opened bottle water can rapidly become contaminatedQuality consistency is dependent on storage duration

Table 8: Common misconceptions about in-house water purification systems.

 Choosing an in-house water purification system
We hope that we have convinced you that an
in-house water purification system can:• Help ensure you’re using the correct water foryour experiment – improving your chance ofachieving accurate and reliable results• Save you time and money• Reduce your impact on the environment

So, if you’ve now come to the decision that installing a purification system is the best solution for your laboratory,
there are a still some other practical factors you need to consider that will influence which system to select –importantly, how much space you have and how many laboratories you need it to serve.
Every laboratory is unique - there is no ‘one size fits all’ for an in-house water purification system.
In addition, you will want to consider the following questions:• Will your users need to use it for a broad range ofapplications, or just restricted to a particular one?

• How much pure water will you use, on average,
per day?

• What will be the peak times and how will you
keep up with demand?

• What about your laboratory water feed quality –• Will your laboratory need the ability to validate
and track water purity?

• Is there a need for accessory systems, such asdegassing?

• What other apparatus – such as primary treatment
process, reservoirs, ‘polishing’ storage ordispensing - will you need as well?

will it need pre-treatment?

• What types of water quality do you need?

We know your time is best spent focusing on getting accurate and reliable results from your experiments.
So why not save time by leaving your most important reagent to ELGA LabWater purification technologies?
Our representatives will be happy to analyze your feedwater and discuss the various options with you,providing expert advice to help you to select a system that best meets your needs.
Our experts understand how important it is for scientists to have a choice of water qualities that range
from primary grade for simple routine washing and rinsing, through to ultrapure water for the most criticalapplications. With our wide range of systems , we can help you choose the right one for your laboratory,
enabling you to achieve the correct level of water purity for your applications, cost-effectively.
Our reliable water purification systems are constructed from the highest quality components to ensure
optimal purity, while a rapid and easy sanitization program contributes towards an uninterrupted workflow. Built-in economical processes result in the lowest consumable costs consistent with the highest
water quality and precision.
When combined, the technologies used in ELGA equipment can remove impurities from water down to
extremely low levels; some technologies focus on specific contaminants while others have a broader
spectrum of targets (Table 7). To achieve the correct water purity for a particular application, in a costeffective manner, we arrange a combination of different technologies and optimize their operation.

Technologies used in ELGA systems:• Activated carbon – in pre-treatment cartridges, composite vent filters and final purification cartridges.
• Microporous Depth Filters – to treat water before it enters the ELGA purification process, these filters act toprotect subsequent RO systems from fouling and blockage.

• Reverse Osmosis (RO) – uses pressure to push purified water through a semi-permeable membrane and toreject contaminants that are >1nm diameter.
1
9

8

7

6

5
4
3

1

1

Feedwater

2
3
4
5

Product Spacer

6

Permeate

RO Membrane

7

Concentrate

Feed Spacer

8

Permeate

RO Membrane

9

Spiral-wound RO Module

2• Ion Exchange – often used as part of a final treatment step.
• Electrodeionisation (EDI) – combines ion-exchange resins and ion-selective membranes. This technology canbe used as an alternative to single-use purification cartridges.

• PureSure® Technology – in all deionization processes, there is a risk that weakly ionised impurities will elutefrom the resins and into your application as they approach exhaustion (this happens even before theresistivity has fallen below 18.2 MΩ-cm). But ELGA’s unique PureSure® technology prevents this, ensuring
your water quality is maintained. This double purification pack and monitoring system ensures accurate
results with uninterrupted workflow, by retaining any organics and silica that may be released by the first
purification pack as it approaches exhaustion and providing you with the time to change the consumable.

1

4

2

3

1

Primary purification pack2

Intermediate water quality sensor R1

3

Output water quality sensor R2

4

Polishing purification pack• Real Time TOC monitoring – an ultra-rapid TOC monitor, this provides a reliable and timely indication oforganic purity.

• Ultraviolet (UV) Light – Typically the UV lamp forms part of a ‘polishing’ treatment loop including ionexchange, through which water is repeatedly circulated to maintain quality.

• Sub-micron filtration - including micro, ultra-micro and ultrafilters (1-200nm) are used as part of a ‘polishing’
loop or at the point-of-use (POU).

• Integrated filters – the PURELAB® Chorus provides integrated ultrafiltration and microfiltration systems. This
integrated system provides a more effective total system approach, combining technologies such as RO, ion
exchange, UV and micro- or ultra-filtration to provide ultrapure water rather than relying on a single pointof-use (POU) system. The benefits of this over typical POU filters are:• Levels of bacteria or endotoxins can be further filtered or recycled before use, as integrated filters arecleared of impurities by recirculating ultrapure water through them.
• Extra security and peace of mind, as monitoring of the final water quality is possible.

• Recirculating – recirculating purified water through the systems purification process ensures the consistent

supply of ultrapure and pure laboratory water. Passing the water repeatedly through a UV chamber andpurification media removes bacteria and other impurities on an ongoing basis, minimizing build-up. This isthe best option for maintaining low contamination levels. You can be sure that the water you are dispensing
is of the highest quality at the point of use.

So, if you are looking to install an in-house water purification system for:A research laboratory:• Our award-winning PURELAB® range of water

purification systems provide different options to fit
your budget and requirements. From primary grade
water for simple routine washing and rinsing - toultrapure water for the most critical science andanalytical applications – we can help you choose
the system that suits you best. The PURELAB Chorus
range of systems are modular, powerful and highly
flexible, so you can design and specify the precise
system to meet your unique needs, with theconfidence that it can be modified if needed.

A clinical laboratory:• We know it’s critical to have a constant and reliablesupply of ultrapure water. Working in partnershipwith major clinical diagnostic companies, we havedesigned our unrivaled MEDICA® range of clinicalwater purification systems. Our technologies
deliver Clinical Laboratory Reagent Water (CLRW
standard water), ensuring you have a guaranteed
supply 24/7.

Larger laboratories or a whole building:• Look towards CENTRA®, which has revolutionized the way that large volumes of pure water are produced,

stored and distributed. Instead of a central laboratory system cobbled together from different components,
you can have just one integrated system box, offering an economic alternative, with savings from
distribution piping and equipment costs. These can supply Type I to III water at high flow rates, combinedwith the flexibility to integrate other equipment around the system as your laboratory grows.

Discover more about:
PURELAB® MEDICA® CENTRA®

by visiting our website: https://www.elgalabwater.com/products Why choose ELGA?

We are the LabWater Specialists. Since the 1950's, we have been working with scientists to guarantee pure andultrapure water for their experiments and laboratory work, making us the world leaders in water treatment in
the laboratory. As an organization, we are committed to ensuring that the water needs of those working in thelaboratory are met with the highest quality professionalism.
As an integral part of Veolia, the world’s leading water service company, ELGA LabWater provides a reliable sourceof laboratory water that economically meets the required compliancy of all our customer’s scientific and medical
applications.
With more than six decades of experience dedicated to pioneering water purification systems, we are continuing
to apply cutting-edge research with innovative and ergonomic design. ELGA LabWater delivers robust and easyto-install systems that economically meet our customers' ever-changing need for ultrapure water.
We also work very closely with leading laboratory instrument companies to customize water purification
systems for specific applications. Additionally, we play a proactive role with the water standards organizations
which develop and recommend laboratory water quality requirements.
We pride ourselves on being:• Customer-focused – our commitment to developing and providing you with pure water means that you canfocus and concentrate on obtaining accurate and reliable results.

• Innovative – our UK R&D facilities are always looking to provide products dedicated to supplying you with theright water quality for your application.

• Sustainable – our products are designed to have the lowest possible impact on the environment at all stages:
manufacture, in service and at end of life. We can calculate the carbon value of all our products through their
lifetime.

• British Engineered – all our systems are designed in the UK and we are accredited to ISO:9001 and ISO:14001.

But don’t just take our word for it, here are just some of our satisfied
customers in laboratories around the world:“For the foreseeable future, the water quantity and quality from the PURELAB® Pulse meets all our needs. In
addition, the ELGA service department is always available and is very competent. On site response time from an
ELGA technician is very good and the service available by phone is also helpful and has saved Cenix money.”
Cenix BioScience , Germany“Overall, ELGA’s service and technical support are an excellent match for our own operations in South Asia. It’s avery good partnership, with a helpful and dedicated team, and it is good to know that they are always on hand
if a customer has a problem. We have complete peace of mind in the MEDICA systems and the ELGA team; ourin-house engineers know they can depend on the systems to perform reliably, and the customer receives a more
efficient, comprehensive service.”
Brian Hilton, Regional Service Manager for South Asia, Abbott Laboratories“The PURELAB® flex is a very successful system both technically and aesthetically. We are very satisfied with our
choice. The compact design, easy operation and maintenance are ideal. The PURELAB® flex is ready for use very
quickly after it is switched on. It has a good flow rate with a 0.2μm point-of-use filter fitted to the dispenser. It
does not cause any problems to our daily requirements.”
Dieter Dirk, Senior Teacher & Head of Laboratory, Olsberg Vocational College, Germany
ELGA installed a customized skid system for the Biomedical Physical Sciences Building at Michigan State
University, supplying laboratory water to 4 floors of labs. “I am so grateful for your assistance with our RO
system. I’ve saved our department thousands of dollars.”
Melissa Parsons, Biomedical Physical Sciences, Michigan State University“Veolia demonstrated through the quality, accuracy and flexibility of its standalone PURELAB units that it coulddeliver a comprehensive solution for a wide range of applications.”
Fiona May, Senior Laboratory Technician, Imperial College London, Department of Life Sciences
https://www.veoliawatertechnologies.co.uk/case-studies/imperial-college-london-department-life-sciences“This has been one of the most reliable new systems we have ever installed.”
Chief Engineer of the Oxford Molecular Pathology Institutehttps://www.veoliawatertechnologies.co.uk/case-studies/bespoke-laboratory-central-water-system“We must be sure that what we are analyzing has come from the sample and is not due to contaminants
introduced into the bottle, and our ELGA water purification systems ensure that we have ultrapure water
constantly available.”
Dr Warren Cairns, Analytical Chemist at CNR Institute , University of Venice, Italy
https://www.elgalabwater.com/about-us/case-studies/unlocking-secrets-antarctic-aid-ultrapure-water Working with ELGA

We hope that the information presented here is useful and you can now better appreciate that:• Selecting the right level of water purity for your application will help you to achieve consistent,
accurate results• For most users, installing an in-house purification system offers an attractive long-term solution that cansave you time and money and reduce your impact on the environment

By choosing ELGA, you will work with one of our representatives who will help you to select an optimal in-housewater purification system for your laboratory – helping make sure that you have access to a guaranteed source ofpure water for your experiments.
At ELGA, we do not speculate or work on assumptions about your water quality. On our first visit to yourlaboratory, we will carry out a test, on site, that checks your feed water quality. We will also work closely withyou to fully understand your laboratory water requirements, providing expert advice to help you to select thebest system for your situation.
We also understand that future needs change and so we have developed a unique and modular set of solutions
that can grow as you and your laboratory grow. So, you do not need to feel restricted to one solution for the next
10 years.
And it doesn’t stop there - we develop long-term relationships with our customers. With a network of over 600
service centers worldwide, ELGA guarantees an unrivaled package of service and support, no matter where youare, for our entire range of water purification systems.

• Our highly-trained service engineers will apply their expertise to the installation, validation and maintenanceof your water purification system. Before, during and after the installation, our validation engineers willanswer any questions you have regarding the process.

• We can provide tailored user training, and our products all come with easy to use manual and quick

consumable guides. You will be able to choose from a wide range of services depending on your application,
operation and budget.

• ELGA also provides a validation support service for our water purification systems.

 References1.

Based on research from the European Commission (DG ENV, June 2009) Final Report, Study on water
performance of buildings – http://bit.ly/1iY3e0S; University of Oxford, Water Management Strategy
Report (January 2011) and AECOM Ltd – http://bit.ly/1m3JEjD

2.

Rana Nabulsi, Mousa A. Al-Abbadi; Review of The Impact of Water Quality on Reliable Laboratory Testing
and Correlation with Purification Techniques, Laboratory Medicine, Volume 45, Issue 4, 1 November 2014,
Pages e159–e165, http://bit.ly/2BxkCX3

3.

Ander EL, Watts MJ, Smedley PL, et al. Variability in the chemistry of private drinking water supplies andthe impact of domestic treatment systems on water quality. Environmental Geochemistry and Health.
2016;38(6):1313-1332. http://bit.ly/2BzzZ1l

4.

Master S, Welter GJ, Edwards M. Seasonal variations in lead release to potable water. Environmental
Sciences and Technology 2016 May 17;50(10):5269-77. http://bit.ly/2BAdV6x5.

ASTM International. Standard Specification for Reagent Water. Active Standard ASTM D1193. Developedby Subcommittee: D19.02. https://www.astm.org/Standards/D1193.htm

6.

International Standards Organisation. ISO 3696:1987. Water for analytical laboratory use – specificationand test methods. https://www.iso.org/standard/9169.html

7.

Clinical Laboratory Standards Institute (CLSI). GP40: Preparation and Testing of Reagent Water in theClinical Laboratory, 4th Edition. https://clsi.org/standards/products/general-laboratory/documents/gp40/

8.

Urbina MA, Watts AJR, Reardon, EE. Environment: Labs should cut plastic waste too. Nature 528, 479 (24December 2015) https://www.nature.com/articles/528479c

9.

ELGA Application Note: Type I ultrapure water crucial for HPLC and UHPLC.

10. Whitehead P. Importance of pure water in modern ion chromatography. Lab Manager
Magazine, November 2010.

The LabWater Specialists
ELGA is an integral part of Veolia, the global leader in optimized resource
management. Veolia has a worldwide team of over 200,000 people andis renowned for its capabilities in providing water, waste and energy
management solutions that contribute to the sustainable development ofcommunities and industries.
The ELGA team focuses exclusively on water and its purification. It continuallycontributes to the unique technical and scientific applications and expertisedeveloped since 1937. We are experienced in meeting the challenges thatarise during the development, installation and servicing of single point-of-use
water purification systems as well as large projects involving consultation
with architects, consultants and clients.

Get in touch

If you would like to find out more about how ELGA can help you,please get in touch with our experts
ELGA offices and distributors are located in more than
60 countries and are fully trained in all ELGA systems.
To find your nearest ELGA representative, go towww.elgalabwater.com and select your country for contact details.
ELGA LabWater Headquarters
Lane End Business Park
Lane EndHigh Wycombe
HP14 3BY
United Kingdom
tel: +44 (0) 203 567 7300
fax: +44 (0) 203 567 7205
info@elgalabwater.com
www.elgalabwater.com

ELGA is the global laboratory water brand name of Veolia. The information contained in this document is the property of VWS (UK) Ltd,
trading as ELGA LabWater, and is supplied without liability for errors or omissions. © VWS (UK) Ltd. 2018 – All rights reserved.
ELGA®, PURELAB®, CENTRA®, MEDICA® and PureSure® are registered trademarks of VWS (UK) Ltd.