A humidity indicator card is a small chemically treated card placed inside packaging to provide a visual record of whether relative humidity exceeded defined thresholds during storage or transit, supporting quality assessment and dispute evidence.
In trade practice
Cards are typically inserted into packaging of dried fruit, nuts and other moisture-sensitive commodities before sealing, with the threshold levels chosen to match the product’s critical water activity limits. On receipt, quality teams photograph the card as part of intake inspection; a colour change beyond the agreed threshold can support a quality claim against the carrier or supplier. Cards must be compatible with the storage temperature range, as some formulations are not reliable at sub-zero conditions. Suppliers should document card specification and placement in their packing records.
In a specification
A specification may require humidity indicator cards calibrated to a stated relative humidity threshold, with card type and placement position recorded in the packing protocol.