Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 15·2.16
Visibility of discharge from safety devices
Discharge from safety devices must be visible both at the tundish and at the final point of discharge to confirm the system is functioning.
The discharge from a safety device which may consist of scalding water and steam, should be visible at the tundish and should also be visible at the final point of discharge.
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