Clean Equipment Hold Time (CEHT)

Duration for maintaining cleanliness

Clean equipment hold time (CEHT, CHT), also called clean hold time, is defined in PDA TR29, Points to Consider for Cleaning Validation, as "the time from the end of the cleaning process until the equipment is used again". During development, the clean hold time to be validated is determined through an assessment which will consider the environmental control of the area, the storage condition of the equipment, production schedule, among other aspects. During validation, the equipment surfaces are tested utilizing a sampling plan after the determined hold time is exceeded. A validated clean hold time allows equipment to be cleaned and stored in a ready to use state until the hold time has expired.