­­~ Abbreviation GUIDE ~
­­~ What Is PURE WATER? ~


­­~ What Is RESIN? ~

­­~ What Is a DI VESSEL? ~

­­~ What Is a TDS METER? ~

­­~ What Is a PRE-FILTER? ~

­­~ What Is a CARBON BLOCK Filter? ~

­­~ Do I Need INSURANCE? ~

– What Is PURE WATER? –

What Is Pure Water?

The term Pure Water in window cleaning describes ordinary tap water that has been filtered through a purifying filter system. This removes natural minerals from the water including Calcium which is the the main cause of white spots on the window when they dry. 

Water is purified through an Reverse Osmosis (RO) System or DI Vessel (De-Ionisation) or a system that combines the two technologies in a single set up. 

The Benefits of Cleaning with Pure Water?

Watch the excellent Introduction Video from our friends at UNGER®
explaining some of the benefits of using a Pure Water Cleaning System

How Do I Test Water Purity?

You can test your treated tap water with a TDS Meter which measures electrical conductivity and produces a value indicating the level of dissolved solids in the water. For window cleaning purposes, a value close to 000ppm (parts per million) of dissolved solids is low enough to leave a streak and spot free finish on the glass. It's reasonable to effectively clean windows with readings of up to 10ppm.





Reverse Osmosis (RO) is a water purification technology that uses semipermeable membranes under pressure to remove large particulates from water. Reverse osmosis can remove many types of molecules and ions from solutions, including bacteria, and has many industrial applications. Ro systems are becoming increasingly popular in the home for producing filtered drinking water.

How Does Reverse Osmosis Work

Reverse osmosis uses ion exclusion to force water containing undesired contaminants through a semi-permeable membrane. A concentration of ions at the surface of the membrane permits the passage of water molecules while rejecting contaminates and impurities.

In window cleaning systems, the purified water from the RO becomes ionically charged by passing it through a De-Ionisation unit called a DI Vessel. The effect is such that the water dynamically attracts dirt, dust, mineral deposits and various organic materials when applied to the surface of the window glass.

NASA Technology

The development of efficient portable water purification systems were a direct technological spin-off from scientific research following the need to effectively recycle water aboard the International Space Station. Innovations in the design of Forward and Reverse Osmosis systems and membranes combined with improvements to small powerful pumps and deionisation filters have found wide applications around the globe.

Watch the VIDEO
to see how NASA RO Water Purification Systems
are changing the world

Pure Water Cleaning Systems

Custom built RO systems provide a highly effective means of removing contaminates which can compromise the effectiveness of DI filtration. However, an alternative carbon pre-filter method can be a cost effective alternative for  producing ionically charged water, but in general the carbon block filters are a more effective method of removing contaminants.

RO Membranes

Here at Window Cleaning Warehouse, we supply PREMIUM QUALITY Filters and Membranes by leading manufactures such as GE Merlin, PENTAIR, Spectrum™ Filtration and AXEON® Water Technologies. Good quality RO Membranes are an essential part of any Pure Water System.

View AXEON® Reverse Osmosis GUIDE



– What Is RESIN? –

What Is RESIN?

Resin is essential to the preparation and purification of your tap water. Usually referred to as Ion Exchange or Mixed Bed Resin, it is an insoluble substance in the form of spherical beads around 0.5mm-1mm in diameter.

How Does RESIN Work?

Ion Exchange Resin works by altering the ion charge of soluble particles in the water itself. Contained within the polymer spheres are insoluble acid or alkaline chemicals that have the ability to remove the ‘hard’ compounds (Calcium, Magnesium) of water that is passed through the resin and replace them with Sodium.

This Ion Exchange is primarily used in water treatment, however, a by product of producing water that is biased towards being pure, is that water itself will now appear to be ‘charged’. In this state the water becomes naturally attracted to particles and dirt on the window glass, effectively binding to these impurities and pulling them from the glass.

This process happens within a DI Vessel which channels the tap water through the resin. A Pre-Filter is often used initially to remove larger particles from the water which can make the De-Ionisation process less effective. Resin requires replacing regularly as it becomes saturated with ionically charged particles from the tap water.



– What Is a DI VESSEL? –

What Is a DI VESSEL?

A DI Vessel is a controlled container which effectively channels impure tap water through the Mixed Bed Resin and is an essential component of a Pure Water System.

DI Vessel is commonly the final process of a complex series of filters and membranes that prepare the tap water before passing through the resin container. A Pre-Filter is recommended to remove particles of dirt and dust that can damage the delicate membranes involved in the De-Ionisation process. In high volume systems, multiple DI Vessels are used to maintain an efficient throughput.



– What Is a TDS METER? –

What Is a TDS METER?

A TDS Meter is a device that measures  the electrical conductivity of water and since pure water has virtually zero conductivity, it is possible to determine with certain accuracy the TDS  or Total Dissolved Solids present in  your local tap water.

Handheld Digital TDS Meter

HM Digital® are one of the foremost manufacturers of inline and handheld TDS Meters


What are Total Dissolved Solids?

Total Dissolved Solids (TDS) are the total amount of mobile charged ions, including minerals, salts or metals dissolved in a given volume of water, measured in parts per million (ppm). The TDS value can also indicate the quality of water purification systems themselves.

Graph of Average Total Dissolved Solids in Purified and Common Tap Water Values
Measured in Parts per Million


What are Impurities?

The dissolved solids that affect the purity of water originate largely from organic solids combined with various salts and mineral deposits such as calcium bicarbonate, nitrogen, iron phosphorous and sulphur. Inorganic materials like stone dust can also contribute to the level of impurities as they dissolve and deposit other metallic and non-metallic compounds. These salts and minerals dissolve in water to form positively and negatively charged particles called ions.



– What Is a PRE-FILTER? –

What is a PRE-FILTER?

A Pre-Filter is installed before the Reverse Osmosis Membrane in a Pure Water Filtration System and is Designed to Trap Coarse Sediments which can Damage the RO Membrane

They vary in size and shape depending on the installation and proposed use case. Various factors can effect the efficiency of your system and selecting the correct Pre-Filter is vital to provide adequate protection for the RO. 

Why are they Important?

Reverse Osmosis membranes are delicate structures and can be prone to contamination from silt, sand or other large particulates. It's important to understand what level of Pre-Filter is optimal for your system and there are several factors to consider.

  • Water Source — Tap Water, Rainwater, Bore Hole etc.
  • Mineral Content
  • Geographical Location
  • Capacity

Types of Pre-Filter?

There are three principal types of Pre-Filters used in Water Fed Pole Systems:

  1. Water Softening Filters
  2. Sediment Filters
  3. Carbon Filters — Carbon Block or GAC (Granular Activated Carbon)

Water Softening can be beneficial in hard water areas, providing an additional layer of protection.
Sediment and Carbon Filters are commonly installed in window cleaning systems.



– What is a CARBON BLOCK Filter? –

What is a CARBON BLOCK Filter?

Carbon Block or Granular Activated Carbon (GAC) Filters are used to remove chlorine, some sediment and volatile organic compounds before the RO Filtration System.

Carbon Pre-Filters protect the membrane from damaging chemicals. Chlorine damage, for example, is a common problem and is irreversible. Chlorine damaged RO membranes produce poor quality water with dramatically reduced efficiency requiring replacement membranes long before they are due.

Granular Activated Carbon (GAC) filters are less common than Carbon Block and are mainly used in domestic drinking water systems that use an alternative method of filtration. In general, for Window Cleaning Systems, Carbon Block filters are a more effective and economical method of removing contaminants.



– Abbreviation GUIDE –

Window Cleaning Abbreviations

The window cleaning industry has many abbreviations and initialisms that can cause confusion even for experienced window cleaners

Popular Water Fed Terms

  • PPM - Parts Per Million - A measured quantity of Total Dissolved Solids.
  • TDS - Total Dissolved Solids - Another measurement to indicate the purity of  your water.
  • TDS Meter - An electronic meter for accurately measuring Total Dissolved Solids. Provides a continuous digital readout to assess water quality.
  • DI - Deionisation - A chemical process that uses manufactured resins to filter dissolved minerals and impurities through a DI Vessel.

  • RO - Reverse Osmosis - A  technology using semipermeable membranes to remove larger particulates from water, often used alongside Deionised filtration.

  • Payload - The total weight of equipment, tank and water that a fitted vehicle can safely transport.
  • WFP - Water Fed Pole - A lightweight, specially designed extending pole.
  • Pole Pipe - A flexible, small bore water hose threaded through a Water Fed Pole. 
  • HiMod - HiModulus Carbon Fibre - A strong but light material used in the construction of high quality Water Fed Poles.
  • GAC - Granular Activated Carbon. A type of Carbon Pre-Filter.
  • Micron - A term used to describe the average size of the openings between pieces of the filter media.


  • IOSH - The Institution of Occupational Safety and Health - The only chartered body for Health and Safety practitioners - Plain English means they know what they are talking about when it comes to Health and safety!
  • NEBOSH - National Exam Board in Occupational Safety & Health - Again they know the in's and out's on Health and Safety.
  • HSE - Health and Safety Executive - The knowledge on Health and Safety at work.
  • CRB - Criminal Record Bureau (now called DBS, see below)
  • DBS - Disclosure and Barring Service - A check on a person's criminal background and history to see if they are barred from working in specific areas.
  • CHAS - The Contractors Health & Safety Assessment Scheme - A scheme to prove you meet the required standards of health & safety of specific public and private sector businesses.
  • CSCS - Construction Skills Certification Scheme - A certification to prove you have the required training to work on a construction site.
  • FWC - Federation of Window Cleaners.
  • FSB - Federation of Small Businesses.
  • IRATA - Industrial Rope Access Trade Association - Global Association for working at height . Provides working guidelines and training for rope access work.
  • IPAF - International Powered Access Federation - Promotes the safe and effective use of powered access equipment.
  • PAL - Powered Access Licence - If you complete an IPAF course you are awarded a PAL Card.
  • SAM - Safety Accredited Member - Safety accreditation for window cleaning.
  • MEWP - Mobile Elevated Working Platform - Otherwise known as cherry pickers, access platforms or Scissor lifts.
  • PASMA - Prefabricated Access Suppliers and Manufacturers Association - Trade association for mobile access tower industry.

Other Abbreviations

  • WCW - Window Cleaning Warehouse Ltd The UK's Largest and Best Supplier of Window Cleaning Equipment.
  • WC - Window Cleaning, plain and simple.
  • Shiner - Common term for a Window Cleaner.
  • Windie - Alternative name for a Window Cleaner.
  • Trad - Abbreviation for the term Traditional Window Cleaning.
  • T-Bar - Traditional Handle used to apply soap to a window surface. Combined with a absorbent sleeve. Also called an Applicator.



– Do I Need INSURANCE? –

Do I Need Insurance to be a Window Cleaner?

If you employ staff even if they are self employed then you are legally required to have insurance. If you do not employ anyone or you sub-contract, arranging for another business to carry out work on your behalf, then the law  does not require insurance, however, we strongly recommend you consider public liability insurance at the very least.

Why Should I Consider Insurance?

  • Commercial clients often require you to have insurance before workong on their premises.
  • Insurance is also required for subcontracted work.
  • You will be covered for accidents involving property damage or members of the public.
  • Specialised industry insurers can provide tailored cover against damage to property during window cleaning. This is always good to have if you happen to break a window! This is called 'Damage to Property Worked Upon'.
  • Trade federations such as Scottish Window Cleaners License  or The Federation of Window Cleaners usually require your business to have adequate insurance to be included in their membership.

Which Insurance Should I Choose?

The level of insurance cover you require will depend on your particular business requirements especially if you have employees. Check out our own affiliated broker below for more information about the particular type of insurance which you will need as part of your window cleaning business.

Geza Hajgato
Cert Cll

01446 728281
07469 170120