Manual Thermometers
Mercury, non-mercury (liquid in glass), or bimetallic thermometers with analog displays, for general and application-specific use, with various temperature-range capacities and accuracies; may be traceable or certified to international standards.
In 1714, the mercury-in-glass thermometer was invented in Europe by physicist Daniel Gabriel Fahrenheit. Typically, the mercury is contained in a reservoir that opens to narrow glass tube. The distance that the mercury flows into the tube is dependent on the temperature to which the thermometer is subjected. The space above the mercury may be filled with air or an inert gas, or it may be a partial vacuum.
Thermometers are calibrated by exposing them to a known temperature and then marking the height of the mercury at that temperature. For example, one might calibrate to the freezing temperature of water (0°C or 32°F) by placing the thermometer in a mixture of ice and water. Then the thermometer could be submerged in boiling water to determine the point where the water changes from a liquid to a vapor (100°C or 212°F).
Mercury thermometers are still considered to be some of the most accurate temperature indicators. They can be used for a wide range of temperatures, from -37°C to 356°C (-35°F to 673°F). Modifications such as adding an inert gas above the mercury or replacing the glass with fused quartz can extend the upper temperature limit to as high as 800°C (1,470°F).
Mercury cannot be used below -38.83°C (-37.89°F), the temperature at which it becomes a solid. Moreover, nitrogen in the thermometer can flow down into the column and become trapped if the mercury solidifies, which makes the thermometer unusable. Use a thermometer that contains a mercury-thallium alloy for measuring lower meteorological temperatures – it will remain liquid to -61.1°C (-78.0°F).
Thermco Products Inc NIST Traceable - Factory Certified Non-Mercury Glass Thermometers - Spirit Filled
Range: -1/201°C | Div: 0.2°C | Length: 610mm
Chemglass Life Sciences Thermometer, Non-Mercury, 10/18 Joint, 51mm Immersion, -20C to 150C
Thermometer, Non-Mercury, 10/18 Joint, 51mm Immersion, -20C to 150C. Thermometer is mineral spirit filled to eliminate workplace and environmental hazards associated with mercury. Thermometer has a white back, a 6 to 7mm outer diameter, and a standard taper 10/18 inner ground joint. All ranges have 1° subdivisions. Immersion is measured from the bottom of the joint to the bottom of non-mercury bulb.
Cole-Parmer Digi-Sense Calibrated Liquid-In-Glass Thermometer; -50 to 50C, Total Immersion, Organic Liquid Fill
These thermometers are ideal for use in applications where a very precise accurate temperature measurement is required. Thermometers are individually calibrated to NIST standards at specific temperatures and supplied with an NIST report of calibration stating corrections to one-tenth the smallest division. Thermometers feature triangular anti-roll fitting, permanently fused markings, blue spirit liquid, white background glass; are also individually serial numbered. Include an NIST-traceable statement of accuracy and a triangular-style antiroll fitting.
Hach Company Thermometer, 0-200° C
Bi-metallic. Dial gauge 0 to 200°C ±1%. Two degree divisions. Probe diameter is .15 inches. Plastic carry case with clip.
Thermco Products Inc Precision Non-Hg, Taper Joint thermometer, Spirit, -10 deg./250 deg.C, 1.0C div, 50mm imm, 350mm, 10/30 taper
Manufactured with a 10/30 glass standard taper joint to fit in 10/30 joint of flasks and other laboratory glassware. Accurate to N.I.S.T. tolerances. Individually serialized. Thermometer may be Safety-Coated with TFE. Filled with a safe red spirit filling for safety purposes.
Cooper Atkins Corporation Thermistor Temperature Instrument
For those applications where only one temperature is read at a time, the TM99A is an industry standard. It features Min/Max memory, hold, auto shut-off. LCD backlight for dark environments. The TM99A includes a pouch and 1075 general purpose probe.