There is no fixed answer to “how many readings?” on a temperature form. Room geometry, racks, airflow, product conditions and usage determine the measurement plan.
Define mapping scope first. Add room dimensions, rack positions, evaporator, doors and typical empty or loaded conditions to a layout. Plan mapping with a competent technical person; state sensor locations, logging interval and operating scenarios in the protocol. One universal number of points does not fit every store.
Use the results to select representative monitoring points and alarm or action limits based on product conditions and the quality procedure. Do not confuse mapping points with routine or continuous monitoring devices; mapping supports the rationale for device placement.
Minimum fields for the log
Point code and location, date and time, monitoring device and calibration status, value, product or room load, alarm or excursion, action taken and responsible person. The quality system should determine when mapping is reviewed after sensor location or room use changes.
