Do you work outdoors where potentially explosive gases might be present, or do you work on the floor of a processing plant? If so, you need a reference thermometer designed to go where you work.

Industrial reference thermometers available on the market today, such as mercury-in-glass thermometers (or “ASTM thermometers”) and portable electronic thermometers, are useful, but both come with inherent problems.

Although accurate and repeatable, mercury thermometers are fragile.

The risk of a mercury spill poses potential hazards to the environment and to the health of personnel. Many of the United States and European Union countries have already banned the use of ASTM thermometers in industrial applications. Some organizations have replaced their mercury thermometers with more durable portable electronic thermometers, only to discover that the resistance temperature detector (RTD) probes lack the reliability and dependability required of a legitimate reference thermometer.

The stainless steel probe sheath of the?1551A/1552A “Stik” Thermometer?is far more robust than the glass stem of a mercury thermometer and better suited for industrial environments. And since the “Stik” thermometer does not contain mercury, the risk of an accidental mercury spill is eliminated.
Mercury thermometers cannot be adjusted after calibration. The actual temperature must be calculated by applying corrections to the measured temperature. This takes time and is susceptible to calculation error. A digital thermometer does the math for you—the displayed temperature accurately represents the actual measured temperature.

Using a glass-stem mercury- or spirit-filled thermometer at different immersion depths, or at significantly different ambient temperatures from which it was calibrated, might require the application of emergent-stem corrections that can be tedious but necessary to calculate an accurate measurement. These corrections aren’t required with the “Stik” Thermometer. The sensor of the 1551A Ex requires a minimum immersion depth of only 2.8 inches (7 centimeters), with no appreciable effect on the measured temperature due to heat loss through stem conduction.
When considering cost of ownership, a digital thermometer is less expensive than a mercury thermometer. With a mercury thermometer, you either invest in equipment or you hire out to clean up after a mercury spill.

This intrinsically-safe, battery-operated, portable reference thermometer is the new “gold standard” of industrial temperature calibration.

Go here for detailed information about the?1551A Ex/1552A Ex Intrinsically Safe “Stik” Thermometer