Optimal Temperature and Humidity Conditions for Ultra-Low Temperature Pharmaceutical Cold Storage

In pharmaceutical ultra-low temperature cold storage facilities, while temperature control (ranging from –30°C to –80°C) is the primary factor in maintaining the activity and stability of highly sensitive products such as mRNA vaccines, recombinant proteins, and cell suspensions, humidity management is equally critical.
Even trace amounts of moisture, if condensed into frost or ice crystals at these low temperatures, can disrupt the three-dimensional structures of biomolecules, leading to irreversible loss of drug efficacy.

Therefore, it is essential to establish a frost-free environment inside ultra-low temperature cold storage and precisely maintain the relative humidity below 20% RH. This minimizes the absolute moisture content in the air and prevents frost formation, protecting both pharmaceutical packaging and internal active components.

Under such dry conditions, the frequency of condenser frost buildup is significantly reduced, preventing the frequent defrosting cycles that cause temperature fluctuations and increased energy consumption. This stability not only preserves the desired storage temperature but also extends the shelf life of pharmaceutical products.

In terms of temperature control, storage temperatures are typically maintained at:

• –75°C to –80°C for Pfizer vaccines, or

• –60°C to –70°C for Moderna vaccines and cellular samples.

Only by achieving a dual dimension of precise temperature and humidity control can we truly ensure the transformation from "simply cold storage" to "quality preservation".

To maintain this "dry-cold" environment continuously, it is necessary to deploy a real-time temperature and humidity monitoring system with an accuracy of ±0.5% RH, sampling at intervals no longer than one minute.
When humidity levels exceed preset thresholds, the system should automatically activate dehumidification or air exchange functions to ensure humidity fluctuations remain within acceptable limits, fully complying with stringent GMP/GDP standards and ICH stability testing requirements.