Types of Thermometers and How To Use Them to Gain Accurate Readings

Section 1: Overview of Thermometer Types

Mercury Thermometers: Often used in laboratory settings due to their high degree of accuracy.
Alcohol Thermometers: Contain red or blue alcohol, used for measuring lower temperatures due to alcohol’s lower freezing point.
Digital Thermometers: Commonly used due to their ease of reading and quick results.
Infrared Thermometers: Non-contact devices that measure temperature from a distance, often used in industrial applications.
Bimetallic Strip Thermometers: Utilise the expansion and contraction of two different metals to measure temperature, usually used in household appliances.

Section 2: Using Thermometers Accurately

For high precision readings, select a thermometer with a small graduation.
Ensure the thermometer is clean and in good condition before use.
Always read the thermometer at eye level to avoid parallax errors.
Allow adequate time for the thermometer to acclimatise to the temperature being measured.

Section 3: Key Tips for Specific Thermometers

Mercury Thermometers should be read at the top of the mercury column.
For Alcohol Thermometers, ensure entire bulb is submerged in the substance to gain accurate reading.
In Digital Thermometers, confirm that the device has been calibrated correctly.
Infrared Thermometers should be operated according to the manufacturer’s instructions, considering the distance-to-target size.
With Bimetallic Strip Thermometers, ensure the full length of the metal strip is exposed to the temperature to be measured.

Section 4: Potential Errors and Precautions

Avoid touching the thermometer stem below the liquid level while taking temperature measurements.
Do not use a thermometer beyond its range, which could cause it to break or provide inaccurate readings.
Handle Mercury Thermometers with care as mercury is toxic. If one breaks, remediate the area properly.
With Digital and Infrared Thermometers, always consider the emissivity of the surface being measured.