Ice Lined Refrigerators (ILRs): A Complete Guide to Safe Medicine Storage
Discover how Ice Lined Refrigerators (ILRs) maintain the ideal 2°C–8°C range for vaccines and other temperature-sensitive medicines, following WHO guidelines and ensuring maximum efficacy.
1. What Is an ILR and Why Does It Matter?
An Ice Lined Refrigerator (ILR) is a specialized cold storage unit designed specifically for temperature-sensitive medical products like vaccines and biologics. ILRs provide a steady cooling mechanism—typically 2°C to 8°C—essential for preserving drug potency. Unlike standard refrigerators, ILRs include a layer of ice (or phase-change material) to maintain consistent temperatures, even during power outages.
2. Understanding Holdover Time
Holdover time refers to how long an ILR can keep the internal temperature stable without external power. Many ILRs remain at 2°C–8°C for 24 or more hours, safeguarding medications during unexpected blackouts or power issues.
3. WHO Guidelines for Temperature-Sensitive Medicines
The World Health Organization (WHO) provides universal standards to protect the efficacy of vaccines and crucial medications:
- Temperature Range: Keep products within 2°C–8°C.
- Routine Monitoring: Use calibrated thermometers or data loggers for real-time tracking.
- Prevent Freezing: Many vaccines lose potency if they freeze (unless specified by the label).
- Regular Inspections: Check the ILR for ice buildup, ensure door seals are in good condition, and keep the unit clean.
4. How Temperature & Humidity Affect Medicine Efficacy
Excessive Heat: High temperatures accelerate chemical breakdown,
reducing a drug’s potency.
Freezing: Some vaccines become inactive if they freeze (when they shouldn’t).
High Humidity: Moisture invites bacterial or fungal growth and can damage
packaging or labels, leading to potential contamination.
5. Correctly Placing Medicines in an ILR
- Pre-Cool the ILR: Verify it’s within 2°C–8°C before loading any items.
- Group Similar Products: Keep vaccines, biologics, and other sensitive items in separate trays or baskets.
- Leave Space: Avoid overcrowding. Air circulation is crucial for consistent cooling.
- Check Expiry Dates: Place soon-to-expire medications at the front for quick access.
- Minimize Door Openings: Each door opening can alter the internal temperature, so keep them brief.
6. Dos and Don’ts for ILR Management
Dos
- Clean and defrost on a regular schedule.
- Use data loggers or digital thermometers for accuracy.
- Have a backup power plan (generator or solar) when feasible.
Don’ts
- Do not overcrowd the ILR or block vents.
- Avoid storing room-temp items without pre-cooling.
- Never mix personal food or drinks with medical supplies.
7. Maintaining Cold Chain Integrity
ILRs are one component of the broader cold chain, which spans manufacturing, transport, storage, and delivery. A lapse at any point can compromise medicine quality. Consistent temperature logs, well-trained staff, and adherence to WHO guidelines help keep vital medicines safe and effective for end users.
Pro Tip: Schedule routine ILR maintenance and sensor calibration to prevent unseen issues and maintain optimal storage conditions.