Window cleaners

Window cleaning, or window washing, is the cleaning of architectural glass used for structural, lighting, or decorative purposes. It can be done manually, using a variety of tools for cleaning and access. Technology is also employed and increasingly, automation.

Commercial work is contracted variously from in-person transactions for cash or barter, to formal tender processes. Regulations, licensing, technique, equipment and compensation vary nationally and regionally.

Chamois is a basic method used to loosen and remove dirt, followed by a buffing with cheesecloth, or scrim.

Generally, chemicals are added to water, and a device such as a brush or cloth-covered handle is dipped into the resulting solution and used to scrub glass. A squeegee is then used to sluice the dirt and water mixture from the glass.

Chemicals added to the solution range from dish soap and glass cleaner to Trisodium Phosphate and etching salt. In sub-freezing temperatures, anti-freezing chemicals are added to the solution to prevent it from crystallizing on the pane before it is sluiced off.

Any of a variety of types of telescopic poles, fitted at the upper end with a brush and water jets, fed either from vehicle-borne tanks of deionised water or by on-site production of deionised water using a domestic or commercial water outlet. The water is filtered by either a two-stage or three-stage filtration process, involving a carbon filter, and two de-ionization filters, or a carbon filter, a reverse osmosis membrane filter, and a de-ionization resin filter. The filtered water contains a TDS (total dissolved solids) of less than 5 ppm. (parts per million.) The brush is used to agitate the debris off the window, while spraying water, and then the brush is lifted a few inches from the glass to rinse the glass with the pure water jets. Fan jets are used for hydrophobic glass, and "pencil" jets are used for hydrophilic glass. The de-ionized water is lacking in ions, so it will pull solids off the glass and dissolve the solids into the water, aiding in the cleaning process. Because there are no solids dissolved in the water, the windows dry clear without water spots. Water-fed poles vary in length. The longest poles are about 70 feet, and can reach up to six storeys. Water-fed cleaning is also referred to as pure water cleaning. It is common in the UK and becoming common in the US.

Where glass is found are window cleaners, and methods of access and equipment related to both access and cleaning vary nationally and regionally. If a window is not easily accessible using one type of equipment then it is advisable to combine different tools to be able to clean it properly.

Ladders ranging in size from a single step to the extent (and beyond) of local regulations are used to access windows for cleaning purposes.

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Wikipedia