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).
Cole-Parmer Digi-Sense Dry Block/Incubator Liquid-In-Glass Thermometer; 20 to 100C, 76mm Immersion, Organic Liquid Fill
These thermometers are designed for use in specific applications. These Durac thermometers feature markings that are permanently printed on the glass, individually serialized, and red spirit liquid that has a dark scale contrasts against a white background. Some thermometers are PFA coated for added safety which may cause a slight change in accuracy up to 1 division. Dry block thermometers - designed for use in all standard heating blocks and water baths with most having arrows indicating critical temperatures.
Tel Tru Manufacturing Company Inc BI-METAL DIAL THERMOMETER LT22
NC3859957 BI-METAL DIAL THERMOMETER LT22
Grainger Liquid Filled Food Service Thermometer
The Taylor 14F311 mechanical food service thermometer is a dial thermometer designed for commercial kitchen use. It has a stainless steel stem that is 5.5 inches long with a 1.5 inch dial face. The dial is color coded to indicate temperature zones from 0-220°F/-18-104°C. It can be calibrated and has a pointed tip for easy insertion into food. The dial is encased in a stainless steel case with a hanging hole for storage. This NSF certified thermometer is ideal for monitoring cooking and holding temperatures of food in restaurants and commercial kitchens.
Cole-Parmer Ashcroft A935AF2 Adjustable Angle Glass Thermometer, 3.5" Stem; 0/120F
FEATURES
- Mercury free blue liquid in glass with magnifying lens for easy readability
- Molded Valox - V-shaped black case for ranges up to and including 300°F
- Die cast black aluminum V-shaped case for ranges above 300°F
- Glass front excludes dust and dirt
- White aluminum scale with bold black graduations and figures
- Accuracy is 0.1% of full scale
- Easy adjustment permits case and stem to be rotated 360°
- 9" scale is standard
- 1-1/4" - 18" NEF swivel nut
Kessler Thermometer Corp -10/210C THERMOMETER NON MER
This item has a minimum qty of 3 per supplier requirements.
Ace Glass, Inc. Thermometer, 0 to 300°F, 12" length, total immersion
0 to 300F, total immersion, enviro-safe economy thermometer. 12 inches long. Thermometer is filled with organic black liquid, and is made from lead-free glass. Does not contain mercury. Comes with a NIST traceable statement of accuracy.
Ace Glass, Inc. Thermometer, 0 to 230°F, 12" length, total immersion
0 to 230F, total immersion, enviro-safe economy thermometer. 12 inches long. Thermometer is filled with organic black liquid, and is made from lead-free glass. Does not contain mercury. Comes with a NIST traceable statement of accuracy.