page_title: Tap (valve)
section_title: Liquid
hierarchical_section_title: Tap (valve) / Types / Liquid
caption_attribution_description: English: Water Tap മലയാളം: പ്ലാസ്റ്റിക് ജല ടാപ്പ്
context_page_description: A tap is a valve controlling the release of a liquid or gas.
context_section_description: Water for baths, sinks and basins can be provided by separate hot and cold taps; this arrangement is common in older installations, particularly in public washrooms/lavatories and utility rooms/laundries. In kitchens and bathrooms, mixer taps are commonly used. In this case, hot and cold water from the two valves is mixed before reaching the outlet, allowing the water to emerge at any temperature between that of the hot and cold water supplies. Mixer taps were invented by Thomas Campbell of Saint John, New Brunswick, and patented in 1880.
  For baths and showers, mixer taps frequently incorporate some sort of pressure balancing feature so that the hot/cold mixture ratio will not be affected by transient changes in the pressure of one or other of the supplies. This helps avoid scalding or uncomfortable chilling as other water loads occur (such as the flushing of a toilet).
  Rather than two separate valves, mixer taps frequently use a single, more complex, valve controlled by a single handle (single handle mixer). The handle moves up and down to control the amount of water flow and from side to side to control the temperature of the water. Especially for baths and showers, the latest designs are thermostatic mixing valves that do this using a built-in thermostat, and can be mechanical or electronic. There are also taps with color LEDs to show the temperature of the water.
  If separate taps are fitted, it may not be immediately clear which tap is hot and which is cold. The hot tap generally has a red indicator while the cold tap generally has a blue or green indicator. In the United States, the taps are frequently also labeled with an "H" or "C". In countries with Romance languages, the letters "C" for hot and "F" for cold are used (from French "chaud"/Italian "caldo"/Spanish "caliente" (hot) and French "froid"/Italian "freddo"/Spanish "frio" (cold)). Portuguese would use Q (for "quente", hot) and F. This can create confusion for English-speaking visitors. Mixer taps may have a red-blue stripe or arrows indicating which side will give hot and which cold.
  In most countries, there is a standard arrangement of hot/cold taps. For example, in the United States and many other countries, the hot tap is on the left by building code requirements. Many installations exist where this standard has been ignored (called "crossed connections" by plumbers). Mis-assembly of some single-valve mixer taps will exchange hot and cold even if the fixture has been plumbed correctly.
  Most handles in homes are fastened to the valve shafts with screws, but on many commercial and industrial applications they are fitted with a removable key called a "loose key", "water key", or "sillcock key", which has a square peg and a square-ended key to turn off and on the water; the "loose key" can be removed to prevent vandals from turning on the water. Before the "loose key" was invented it was common for some landlords or caretakers to take off the handle of a tap, which had teeth that would meet up with the gears on the valve shaft. This tooth and cog system is still used on most modern taps. "Loose keys" may also be found outside homes to prevent passers-by from using them.
  Taps are normally connected to the water supply by means of a "swivel tap connector", which is attached to the end of the water pipe using a soldered or compression fitting, and has a large nut to screw onto the threaded "tail" of the tap, which hangs down underneath the bath, basin or sink.  A fibre washer (which expands when wet, aiding the seal) is used between the connector and the tap tail.  Tap tails are normally ​¹⁄₂ " or 12 mm in diameter for sinks and ​³⁄₄ " or 19 mm for baths, although continental Europe sometimes uses a ​³⁄₈ " (still imperial) size.  The same connection method is used for a ballcock.
  The term tap is widely used to describe the valve used to dispense draft beer from a keg, whether gravity feed or pressurized.
caption: Plastic taps are widely used in India due to low costs.
exif: {"Image ImageDescription": "", "Image Make": "SONY", "Image Model": "DSC-W320", "Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image DateTime": "2012:02:05 08:14:31", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "258", "Image PrintIM": "[80, 114, 105, 110, 116, 73, 77, 0, 48, 51, 48, 48, 0, 0, 2, 0, 2, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0]", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail Make": "SONY", "Thumbnail Model": "DSC-W320", "Thumbnail Orientation": "Horizontal (normal)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail DateTime": "2012:02:05 08:14:31", "Thumbnail JPEGInterchangeFormat": "5688", "Thumbnail JPEGInterchangeFormatLength": "8340", "EXIF ExposureTime": "1/80", "EXIF FNumber": "7/2", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "100", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2012:02:05 08:14:31", "EXIF DateTimeDigitized": "2012:02:05 08:14:31", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "3", "EXIF ExposureBiasValue": "-1", "EXIF MaxApertureValue": "23/8", "EXIF MeteringMode": "CenterWeightedAverage", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "79/10", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2592", "EXIF ExifImageLength": "1944", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "5480", "EXIF FileSource": "Digital Camera", "EXIF SceneType": "Directly Photographed", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Manual Exposure", "EXIF WhiteBalance": "Auto", "EXIF SceneCaptureType": "Standard", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Normal"}