Testo 191-T3 HACCP Temperature Data Logger with Flexible Pt1000 Probe

Overview

The Testo 191-T3 is a certified HACCP-compliant temperature data logger engineered for rigorous thermal process validation and continuous monitoring in food production, pharmaceutical manufacturing, and biotechnological applications. It operates on the principle of high-stability Pt1000 resistance thermometry—providing traceable, NIST-referenced accuracy across extreme thermal gradients. Its core function is to autonomously capture, timestamp, and store temperature profiles during critical controlled processes such as pasteurization, sterilization (including steam-in-place and autoclave cycles), and lyophilization (freeze-drying). The device meets the fundamental metrological requirements outlined in ISO 13485, EN 12830, and FDA 21 CFR Part 11 when used in conjunction with testo’s validated software environment and audit-trail-enabled workflows.

Key Features

• Flexible, High-Integrity Pt1000 Probe: A 775 mm stainless-steel-sheathed probe with 3 mm tip diameter and 1.5 mm shaft enables precise insertion into narrow ducts, product cores, or surface contact points—including freeze-dryer shelves, retort baskets, and heat exchanger surfaces.
• Robust IP68-Sealed Enclosure: The main unit features a monolithic stainless-steel housing with PEEK-coated, tool-free rotating battery cap—ensuring full ingress protection against steam, condensation, and cleaning agents during CIP/SIP cycles.
• Zero-Downtime Battery Replacement: The patented threaded battery interface allows field replacement in under 5 seconds without compromising seal integrity—critical for uninterrupted validation runs exceeding 72 hours.
• Thermal Stability at Extremes: Validated for continuous operation from -50 °C (deep-freeze storage monitoring) to +140 °C (steam sterilization environments), with measurement uncertainty maintained per EN 60751 Class A tolerances.
• Compact Form Factor: At only Ø20 × 63 mm, the logger fits within tight spatial constraints—ideal for placement inside trays, packaging cavities, or between stacked product layers without obstructing airflow or heat transfer.

Sample Compatibility & Compliance

The Testo 191-T3 is explicitly designed for non-invasive and semi-invasive thermal mapping of solid, semi-solid, and liquid matrices in regulated environments. Its flexible probe accommodates direct surface contact on stainless-steel equipment panels, immersion in viscous sauces or dairy products, and interstitial placement within lyophilized cake layers. All materials comply with EU Regulation (EC) No. 1935/2004 for food-contact safety. The device supports HACCP Principle 4 (critical limit monitoring) and aligns with Annex I of EC 852/2004 on hygiene for foodstuffs. When deployed with testo’s validated firmware and calibration certificates (traceable to DKD/DAkkS-accredited labs), it satisfies GMP documentation requirements for thermal process verification per ISO 14155 and USP .

Software & Data Management

Data retrieval, configuration, and analysis are performed via the testo 191 Professional Software—a Windows-based application qualified under GxP guidelines. The software provides full electronic audit trail functionality, including user authentication, change history logging, and digital signature support compliant with 21 CFR Part 11. Users define measurement intervals (1 second to 24 hours), alarm thresholds, and start/stop triggers directly on the PC interface before deploying loggers. The Multi-Station Docking Box (optional, available in 4- and 8-channel variants) enables parallel programming and bulk readout of up to eight units—eliminating serial connection bottlenecks during pre-run setup or post-cycle data harvesting. Export formats include CSV, PDF reports with annotated trend graphs, and XML for integration into LIMS or MES platforms.

Applications

• Pasteurization cycle validation in dairy and juice processing lines
• Autoclave and SIP (steam-in-place) temperature profiling in pharmaceutical cleanrooms
• Lyophilizer shelf and product temperature mapping during primary and secondary drying phases
• Cold chain monitoring of frozen food transport containers and blast freezers
• Surface temperature verification of conveyor belts, filling nozzles, and sealing jaws
• Environmental chamber qualification per IQ/OQ protocols

FAQ

Is the Testo 191-T3 suitable for use inside autoclaves during sterilization cycles?

Yes—the device is rated for continuous exposure up to +140 °C and maintains full IP68 sealing integrity during saturated steam cycles. Its stainless-steel construction and PEEK-coated battery cap resist corrosion and thermal degradation.
Can the probe be calibrated independently of the main unit?

No—the Pt1000 sensor is integrated and calibrated as a complete system. Calibration must be performed on the assembled logger using accredited dry-well or fluid-bath references per ISO/IEC 17025.
Does the logger meet FDA 21 CFR Part 11 requirements out-of-the-box?

The hardware itself is Part 11–capable; full compliance requires use of the testo 191 Professional Software with enabled audit trail, electronic signatures, and secure user access controls—as validated in the software’s IQ/OQ documentation package.
What is the maximum allowable bending radius for the flexible probe?

The probe may be bent to a minimum radius of 15 mm without mechanical damage or drift in thermal response characteristics.
How is time synchronization handled across multiple loggers in a single validation run?

All units are synchronized to the host PC clock during programming. The Multi-Station Docking Box ensures microsecond-level timestamp alignment across up to eight devices, enabling coherent thermal mapping across distributed measurement points.