Warehouse MKT Calculator (GDP)

Good Distribution Practice (GDP) requires medicines warehouses to be temperature-mapped and monitored; CRT areas must demonstrate a ≤ 25 °C MKT at the worst-case location. The authoritative limit is whatever your product's labelled storage condition and stability data specify — read it off the marketing authorisation, the manufacturer's storage statement or the governing pharmacopoeia, and enter your real temperature history against it.

Good Distribution Practice requires that medicines storage areas be temperature-mapped (to find worst-case hot and cold spots across representative conditions), continuously monitored at those points, and demonstrably held within the products' storage conditions. For CRT areas that means showing a ≤ 25 °C MKT at the warmest location, with excursions managed and documented. The responsible person reviews the monitoring and MKT data, and inspectors expect the mapping report, the live monitoring, alarm records, and excursion assessments. Feed your worst-case location's data here to produce the MKT figure that underpins that evidence.

Because degradation is not linear with temperature — it accelerates roughly exponentially (Arrhenius). A simple average treats an hour at 30 °C the same as an hour at 20 °C either side of 25 °C, but the product is harmed far more by the hot hour. MKT weights each reading by exp(−ΔH/RT), so it reflects the true cumulative chemical stress. It is always ≥ the arithmetic mean, and it is the figure regulators expect for storage and distribution compliance.

Use a representative series with durations — typically the logger's interval readings, or summarised blocks of 'X hours at Y °C' if you only have an excursion summary. The more granular the data, the more accurate the MKT, but the result is dominated by the warm excursions, so capturing those accurately matters most. Don't average data before entering it — that defeats the point; enter the temperatures and let the calculator do the kinetic weighting.