A plate's age alone does not show its remaining performance. Combine visual inspection with comparison under matching conditions; assess the result against the applicable product instruction.
Record findings traceably. Log plate ID or batch, model, date, freezing cycle, and observed swelling, cracks, leakage or closure damage. Segregate a plate suspected of damage and mark it for review.
Compare performance under controlled conditions
Prepare plates in the same cabinet, position and duration, then measure with the same device and at the same point. Compare results with intact reference plates and the product's stated temperature instruction; do not infer product temperature from a plate-surface reading alone.
Document the fleet decision
For recurring deviation or shell damage, follow manufacturer/service instructions and the quality procedure. Record the reason, approver and return or disposal route; do not infer a general service life from cycle count.
