You can monitor both temperature and humidity in a single shipment by using a combined datalogger that records both parameters simultaneously throughout transit. Many shipments require this dual monitoring because temperature and humidity together determine whether a product stays safe, fresh, or structurally intact. This article covers which shipments need both, how the technology works, and what to look for when choosing a logger.
What types of shipments require both temperature and humidity monitoring?
Shipments that require both temperature and humidity monitoring are those carrying goods that can be damaged by moisture as much as by heat or cold. Fresh produce, cut flowers, pharmaceuticals, seeds, and certain chemical products all fall into this category. For these goods, controlling temperature alone is not enough — humidity levels directly affect shelf life, product integrity, and delivery quality.
Fresh fruit and vegetables are a clear example. If humidity drops too low during transport, produce loses moisture and wilts. If it climbs too high, condensation encourages mold and bacterial growth. The same principle applies to cut flowers, where the wrong humidity level can cause premature wilting or fungal damage within hours.
In the pharmaceutical and life sciences sector, humidity control is equally critical. Certain medications, biological samples, and diagnostic materials are sensitive to moisture and can degrade rapidly if exposed to the wrong conditions during transport. Blood and organ transport, for instance, requires tight environmental control across both dimensions to maintain viability.
Seeds and agricultural products are another important category. Seeds that absorb too much moisture during shipment can lose germination rates, making humidity tracking essential for companies like seed exporters and agricultural suppliers. For all of these product types, a single datalogger that captures both temperature and humidity gives a complete picture of the shipment environment from start to finish.
How does a single datalogger measure both temperature and humidity?
A single datalogger measures both temperature and humidity using an integrated sensor that detects two environmental variables at once. The most common technology used is a capacitive humidity sensor paired with a temperature sensor, both housed within the same device. The logger records readings at set intervals and stores them as a continuous log for the duration of the shipment.
Capacitive humidity sensors work by measuring how much electrical charge a material holds as moisture in the air changes. When humidity rises, the sensor material absorbs more water vapor and its capacitance changes, which the device converts into a relative humidity reading. The temperature sensor — typically a thermistor or similar component — works alongside it, since temperature affects how humidity is interpreted and reported.
Because both sensors are embedded in the same unit, readings are time-stamped together. This matters because temperature and humidity interact: a drop in temperature can cause relative humidity to spike even if the absolute moisture level stays the same. Having both data streams in one log makes it easier to identify exactly when and where conditions went outside acceptable ranges during a shipment.
What are the cold chain compliance requirements for humidity monitoring?
Cold chain compliance for humidity monitoring depends on the product type and the agreed-upon transport specifications between sender and receiver. Different industries set their own acceptable ranges for relative humidity, and these are typically defined in product specifications, quality agreements, or sector guidelines rather than a single universal standard. The key requirement across all sectors is that humidity data is recorded continuously and can be verified after delivery.
In practice, this means the datalogger must provide a complete, uninterrupted record of humidity levels throughout transit, with clear timestamps. For food products, quality managers typically refer to temperature and humidity ranges defined by food safety protocols and buyer specifications. For pharmaceutical shipments, internal SOPs and carrier qualification documents usually define the acceptable humidity window.
What matters most from a compliance standpoint is that the data is tamper-evident, accurate, and retrievable without relying on the receiving party to have special equipment or software. A logger that produces a clear, shareable report immediately upon arrival — without requiring a USB download or proprietary software — makes the verification process significantly simpler for both sender and receiver.
What should you look for in a combined temperature and humidity logger?
When choosing a combined temperature and humidity logger, the most important factors are sensor accuracy, ease of data retrieval, battery reliability, and environmental impact. A logger that performs well on all four reduces both operational risk and administrative burden across the supply chain.
- Sensor accuracy: Look for a logger with certified measurement accuracy for both temperature and humidity. EN12830 certification covers temperature, and you should verify the humidity sensor specification separately. Tighter tolerances matter most for pharmaceutical and seed shipments where small deviations have real consequences.
- Data retrieval method: Traditional electronic loggers require a USB connection or Bluetooth app to download data, which creates friction at the receiving end. Paper-based loggers that use NFC tap technology allow any smartphone to read the data instantly, with no app or dedicated hardware required.
- Battery performance: Battery reliability is often overlooked, but it is critical for longer shipments. The battery in paper-based loggers is often more reliable than in single-use plastic options because it is optimized for a single, fixed-duration task rather than a rechargeable cycle. There is no risk of the battery being partially drained before the shipment starts, and the lithium-free design means it is also flight-safe and easier to handle from a waste perspective.
- Environmental footprint: Electronic dataloggers — whether single-use or reusable — eventually become e-waste and require specialist disposal. If sustainability is a priority, look for loggers that can be recycled through standard waste streams rather than requiring separate e-waste handling.
- Cloud reporting: A logger that automatically uploads data to a cloud dashboard when tapped gives both the sender and receiver immediate access to the full shipment record, without manual file transfers or email attachments.
How Tapp helps with combined temperature and humidity monitoring
Tapp’s paper-based dataloggers are designed to make combined temperature and humidity monitoring straightforward, sustainable, and accessible for any organization shipping temperature-sensitive goods. As the only provider of paper-based datalogger technology, Tapp has built a solution that addresses the most common friction points in cold chain monitoring without adding complexity.
- Dual-parameter logging: Tapp loggers record both temperature and humidity continuously throughout the shipment, giving a complete environmental picture from dispatch to delivery.
- NFC tap, no app needed: Any NFC-enabled smartphone can read the logger instantly. No USB cable, no dedicated app, and no special hardware required at the receiving end.
- Automatic cloud upload: When the label is tapped, data syncs directly to the TappOS dashboard, making the full shipment report immediately available to both sender and receiver.
- Lithium-free and recyclable: Unlike single-use plastic electronic loggers, Tapp’s paper-based loggers contain no lithium and can be recycled through standard paper waste streams globally, reducing e-waste by up to 90%.
- Flight-safe battery: The battery is optimized for single-use transport, meaning it arrives fully charged and performs reliably for the duration of the shipment, including air freight.
If you want to simplify how your team monitors temperature and humidity across shipments, get in touch with Tapp to find out which logger fits your product and transport requirements. You can also book an intro call with an expert to discuss your specific cold chain monitoring needs.
Frequently Asked Questions
How do I know what temperature and humidity ranges to set as acceptable thresholds for my shipment?
Acceptable ranges are typically defined by your product specifications, buyer agreements, or industry guidelines — not a single universal standard. Start by checking your product’s technical data sheet or storage requirements, then align with your logistics partner or receiver on what constitutes an excursion. For pharmaceutical shipments, your internal SOPs or carrier qualification documents will usually define these windows, while food exporters often reference buyer specifications or food safety protocols.
Can a single combined logger handle long-haul or multi-leg shipments, including air freight?
Yes, as long as the logger’s battery life and memory capacity cover the full transit duration, a single combined logger can handle multi-leg shipments seamlessly. For air freight specifically, it’s important to confirm the logger is flight-safe — meaning it contains no restricted lithium batteries that could be flagged by airline regulations. Paper-based loggers with flight-safe batteries are well-suited for international air shipments without requiring special hazardous materials declarations.
What's the difference between relative humidity and absolute humidity, and which one should I be monitoring?
Relative humidity (RH) measures moisture in the air as a percentage of the maximum it can hold at a given temperature, while absolute humidity measures the actual mass of water vapor present regardless of temperature. For cold chain and shipment monitoring, relative humidity is the standard metric used across food, pharma, and agriculture industries because it directly reflects how the environment interacts with your product. Most dataloggers, including combined temperature and humidity loggers, record and report in %RH.
What happens if my shipment shows a humidity excursion — does that automatically mean the products are rejected?
Not necessarily. A humidity excursion triggers an investigation, not an automatic rejection. The next step is typically to assess the severity and duration of the excursion against your product’s known tolerance levels, often through a formal deviation or impact assessment process. In many cases, the product can still be accepted if the excursion was brief and within a recoverable range — but having accurate, timestamped data from the logger is essential to making and documenting that decision.
How often should the logger record readings, and does a higher recording frequency always give better data?
A recording interval of every 5 to 15 minutes is sufficient for most shipments and provides enough resolution to identify when and where an excursion occurred. Higher frequency logging (e.g., every minute) generates significantly more data without meaningfully improving the ability to detect or respond to excursions in most cold chain scenarios. For very short transit windows or highly sensitive products like biological samples, a shorter interval may be warranted — but for standard shipments, a balanced interval keeps data manageable without sacrificing insight.
Can I use the same logger type for different product categories, or do I need product-specific loggers?
The same combined temperature and humidity logger can typically be used across different product categories, since the hardware itself measures the same parameters regardless of what’s being shipped. What changes between shipments is the configured alert thresholds and acceptable ranges, which should be set to match each product’s specific requirements before dispatch. If your logistics operation handles both pharmaceutical and fresh produce shipments, for example, you’d use the same logger model but configure it differently for each product type.
How should I store unused loggers before a shipment to make sure they perform reliably?
Unused loggers should be stored in a cool, dry environment away from direct sunlight, moisture, and extreme temperatures — conditions that could drain the battery or affect sensor calibration before the shipment even begins. Always check the manufacturer’s recommended storage conditions and shelf life, and avoid activating the logger until just before dispatch. For single-use loggers optimized for a fixed duration, starting the recording as close to dispatch time as possible ensures the battery and memory are fully available for the actual transit period.
