Laboratory Thermometers

Made of glass or metal, thermometers are a tool to measure temperature accurately. Glass thermometers have been strengthened through thermal tempering and the traditional one is a long stem with a silver bulb filled with mercury. Alcohol-filled ones are not as precise as the alcohol evaporates but they can read as low as -200 degrees centigrade. Apart from liquid-glass thermometers, electronic devices are increasingly used. Thermistors measure change in electrical resistance and convert it to changes in temperature. A bimetallic strip consists of two different metals bonded together which expand at different rates so the strip is forced to bend. This bending movement deflects a pointer over a calibration scale. This type is low cost but is not as accurate as a glass stem. Infrared thermometers are non-contact devices which convert infrared energy to an electrical signal and often have a laser targeting system. K-type are used for extreme temperatures and have interchangeable probes for air, liquid or surface. Other types include liquid crystal, quartz and gas resistance. Thermometers are basic pieces of laboratory equipment, whether for research, industry or education. They are used for monitoring experiments, maintaining a sterile work environment and calibrating other laboratory instruments and testing materials.

  • Absolute Calibration Ltd

  • ESTS Logiclave

  • Elite Thermal Systems Ltd

  • Lab Unlimited UK

  • Labtek Services Ltd