The Vaisala HM40 Humidity and Temperature Meter is a compact and portable humidity meter at hand everywhere you go. It is an ideal spotchecking tool that is easy to use and provides reliable measurement. It can be used for a wide range of various portable measurement applications. According to a user's needs, the meter is available in two models: standard and with a remote probe.

The interchangeable HMP40S probes connect easily to the HM40 indicator with a snap-on connector enabling convenient use of multiple probes with one indicator. The measurement data can be displayed in numeric, graphic or statistic views. The rugged HMP40S probes are IP65 classified and conform to the ASTM standard F2170-09.

The HM40 includes a user-friendly, large graphical display and easy-to use push buttons. The user interface is simple and intuitive to use, and available in 10 languages. Also, many other settings can be modified by the user to best suit his individual needs. In addition to relative humidity and temperature, the HM40 provides five calculated humidity parameters, all available in both metric and non-metric units.

The HM40 is powered by 2 AA batteries. An external NiMH charger with USB connection and rechargeable AA sized NiMH batteries are available as an option. Each model also comes with a handy belt clip and case.

The Vaisala HUMICAP® Hand-Held Humidity and Temperature Meter HM40 is compact and easy to use - ideal for quick inspections and spot-checking in wide variety of applications; from structural moisture control and air conditioning systems to industrial production processes and life science applications. It has an intuitive and multilingual user-interface and ten language options. Multiple calculated parameters are available: dew point, wet bulb temperature, absolute humidity, mixing ratio, and enthalpy.