The Vaccine Arrived. The Question Nobody Could Answer: Did It Stay Cold the Whole Way?

By Asutosh Shah & Alpesh Shah · Founders, G-Tek Corporation 30+ years in temperature monitoring, recording, and calibration instrumentation.

The box lands on the receiving bench after four days and three handoffs. Inside: temperature-sensitive vaccine worth far more than the shipping cost. The health worker has one decision to make, accept it or reject it, and about thirty seconds of confidence to make it on. Without a vaccine shipping indicator that traveled inside that box recording the whole journey, it’s a guess. With one, it’s a fact.

A shipment’s temperature history is invisible unless something records it inside the box

A single-use vaccine shipping indicator is a device placed inside the shipment that records temperature for the entire journey and shows a clear pass or fail on arrival. The receiver then knows whether the vaccine stayed within its required limits without guessing.

Transit is where the cold chain is most exposed. Multiple handoffs. Unknown holding conditions. A cold room at dispatch and a cold room at delivery tell you nothing about the six hours the box sat on a loading dock in between. Only a device that travels inside the consignment captures the truth the whole trip, not a spot check at either end. This is the same principle behind G-Tek’s vaccine series loggers: the record has to move with the stock.

Match the indicator to the vaccine, not just to “cold”

Choose an indicator configured to the specific vaccine’s temperature profile. Different vaccines carry different limits, so a WHO-PQS shipping indicator is set for defined vaccine types rather than a generic “cold” threshold.

The LM Pro IN074 is configured for defined types: Prevenar, RotaTeq, and A/B and C profiles. Matching the indicator to the product means the pass/fail actually reflects that vaccine’s tolerance, not an approximation. That alignment is what makes the result defensible under WHO PQS TR07.4, the standard governing single-use electronic shipping indicators.

Before You Choose a Vaccine Shipping Indicator: Verify These

• Vaccine profile match: configured for your specific vaccine type and temperature limits
• WHO-PQS qualification: confirm the PQS reference (IN074 → TR07.4) suits your programme
• Journey duration: the active window covers your longest route
• Readout method: how the pass/fail and data are read on arrival
• Single-use fit: right for one-way shipments where the device stays with the stock

Getting this right is exactly what G-Tek Corporation has focused on for over 30 years from Vadodara. The LM Pro IN074 is a WHO-PQS-qualified single-use electronic shipping indicator (PQS reference TR07.4), configured for defined vaccine types. It travels inside the shipment for up to a 40-day journey and gives a clear result on arrival. Its calibration traces to G-Tek’s own NABL ISO/IEC 17025-accredited laboratory, so the pass/fail a health worker reads is one a programme can stand behind.

Single-use or reusable: which fits a one-way vaccine shipment?

For a one-way vaccine shipment, a single-use indicator fits best. It travels with the consignment, records that one journey, and stays with the stock as its temperature record, with nothing to return or reset.

The logic is simple. There’s no reverse logistics to manage, no reset step before the next trip, and a ~40-day active window that comfortably covers long domestic and cross-border routes. On arrival, the LmViewIN074 readout turns the journey into a result anyone can act on: accept good stock with confidence, reject compromised stock with evidence, aligned to WHO Good Distribution Practices. For programmes standardizing across routes, pairing it with the right data logger range closes the full monitoring picture.

Give Every Vaccine Shipment an Answer, Not a Guess

When a vaccine box arrives, the accept-or-reject call shouldn’t rest on hope. A single-use indicator that traveled inside gives the receiver a clear, defensible answer in seconds, with calibration that traces to an accredited lab.

👉 Shipping or receiving vaccines? Share your routes and vaccine types with the G-Tek team and get a clear recommendation on the right WHO-PQS single-use indicator for your consignments.