Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 17·3.2
Reducing the risk of scalding at bath
Hot water supply temperature to a bath must be limited to a maximum of 48°C using an in-line blending valve or other appropriate temperature control device with a maximum temperature stop.
The hot water supply temperature to a bath should be limited to a maximum of 48 ºC by the use of an in-line blending valve or other appropriate temperature control device, with a maximum temperature stop and a suitable arrangement of pipework.
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