testo 608-H1 / testo 608-H2 Digital Thermo-Hygrometer

Overview

The testo 608-H1 and testo 608-H2 are compact, handheld digital thermo-hygrometers engineered for high-accuracy real-time monitoring of ambient temperature and relative humidity in both residential and light industrial environments. Based on capacitive humidity sensing and precision NTC thermistor technology, these instruments deliver stable, repeatable measurements without internal data logging—making them purpose-built for operational verification, environmental spot-checking, HVAC commissioning support, and routine facility condition assessments where continuous observation—not archival recording—is the primary requirement.

Key Features

• High-stability capacitive humidity sensor with long-term drift compensation, calibrated to traceable standards at factory
• Precision NTC temperature sensor with ±0.5 °C accuracy across 0 °C to +50 °C operating range
• Simultaneous display of temperature (°C/°F), relative humidity (%RH), and calculated dew point (°C/°F)
• Large backlit LCD screen with intuitive icon-based interface for rapid field interpretation
• Auto-ranging measurement circuitry ensures optimal signal-to-noise ratio across full specified ranges
• Robust ABS housing rated IP54 for resistance to dust ingress and incidental water splashes
• Battery-powered operation (2 × AAA) with >2,000 hours of typical service life under intermittent use

Sample Compatibility & Compliance

The testo 608-H1/H2 is designed for non-invasive, open-air ambient measurement only—no probe immersion, duct insertion, or surface contact required. It is not intended for use in corrosive, explosive, or high-particulate atmospheres. The device complies with EN 61326-1:2013 (EMC requirements for laboratory and industrial measurement equipment) and conforms to RoHS 2011/65/EU and REACH (EC) No. 1907/2006 directives. While not certified for GLP/GMP-regulated data capture, its measurement uncertainty profile aligns with ISO 7726:2001 (Ergonomics of the thermal environment — Instruments for measuring physical quantities) for Class B instrumentation.

Software & Data Management

These models operate as standalone instruments with no embedded memory, USB interface, Bluetooth, or PC connectivity. All measurements remain transient and unrecorded—consistent with applications governed by ISO/IEC 17025:2017 Clause 7.7.1, which permits manual readout-only devices where documented calibration status and operator competence ensure measurement integrity. For users requiring audit-trail capability, testo recommends pairing the 608-H1/H2 with external loggers such as the testo 174 series, which supports 21 CFR Part 11-compliant data export and electronic signature workflows when deployed with testo Comsoft software.

Applications

• Routine environmental verification in laboratories, server rooms, archives, and museums
• Pre- and post-maintenance checks of HVAC systems and air handling units
• Monitoring storage conditions for pharmaceutical secondary packaging, printed materials, and hygroscopic raw materials
• Field validation of climate-controlled transport containers prior to loading
• Educational demonstrations of psychrometric relationships and dew point behavior
• Compliance screening against ISO 14644-1 cleanroom classification thresholds (as part of broader environmental assessment protocols)

FAQ

Does the testo 608-H1/H2 support data logging or export?
No. These models provide real-time visual readouts only and contain no internal memory or communication interface.
Is calibration certificate included with purchase?
A factory calibration certificate (traceable to national standards) is supplied with each unit; optional accredited calibration per ISO/IEC 17025 is available upon request.
Can this instrument be used in outdoor environments?
It is rated IP54 and suitable for brief outdoor exposure under sheltered conditions, but prolonged direct sunlight or rain contact may affect sensor stability and display readability.
What is the recommended recalibration interval?
testo recommends annual verification against a reference standard in accordance with ISO/IEC 17025 guidelines—or more frequently if subjected to mechanical shock, condensation events, or extreme thermal cycling.
How does the dew point calculation function work?
Dew point is derived in real time using the Magnus formula applied to measured T and RH values, with coefficients optimized for standard atmospheric pressure (101.325 kPa); altitude corrections are not applied automatically.