The State Food and Drug Administration issued a notice a few days ago that starting from January 1, 2026, my country will completely ban the production of mercury-containing thermometers (that is, mercury thermometers).
A few dollars a mercury thermometer is cheap and accurate. Why is it banned to produce and not recommended? Will it be inaccurate to use an electronic thermometer without a mercury thermometer?
The harm is great, so it is forbidden
The temperature measurement principle of a mercury thermometer is: the "mercury" in the thermometer expands and contracts due to temperature changes. The thermal conductivity of "mercury" is very good. Even if the temperature changes only slightly, the volume will change accordingly, so everyone will think The mercury thermometer is very accurate.
However, mercury thermometers are really too fragile. Everyone may have broken mercury thermometers.
If all the "mercury" in a broken mercury thermometer evaporates, a room with a size of 15 square meters and a height of 3 meters can reach an air mercury concentration of 22.2 mg/m³, which is much higher than the national maximum allowable concentration of 0.01 mg/m³.
Excessive intake of "mercury" can cause headaches, dizziness, even coma, convulsions and other symptoms of poisoning. It can also damage children's neurodevelopment and damage the brain.
Source of article: Nutritionist Gu Zhong:
Therefore, many countries including the United States and Europe began to gradually replace mercury clinical thermometers with electronic thermometers more than 10 years ago.
Is the electronic thermometer inaccurate?
According to the "Regulations for Verification of Medical Electronic Thermometers" formally implemented on March 31, 2020, the maximum allowable error of medical electronic thermometers: ±(0.1~0.2)℃, which is almost the same as the maximum allowable error of mercury thermometers (-0.15~0.1)℃ , It will not affect our judgment of the disease based on the measured body temperature.
But why do many friends have the impression that electronic thermometers are inaccurate?
The high probability is because the right is not bought, and the right is useless.
How to measure more accurately?
Buy regular brands + suitable products + use them correctly.
First of all, you must ensure that you are buying qualified products produced by regular brands. This is generally no problem. However, during the epidemic, some black-hearted merchants were greedy for huge profits and produced some counterfeit and inferior electronic thermometers to the market, so they are buying them. It’s better to be careful when choosing channels and stores carefully.
Electronic body temperature measurement products on the market now include non-contact infrared ear thermometers, infrared forehead thermometers, and contact measurement electronic thermometers. (Strictly speaking, they are called electronic thermometers)
"Infrared ear thermometer" can measure the body temperature within a few seconds, but it has higher requirements on the environment and operation methods, and even more earwax may cause inaccurate measurement results.
The "infrared forehead thermometer" also measures the temperature very quickly, but the operation is relatively complicated. It is necessary to select the right mode and avoid overheating or overcooling of the temperature measurement environment.
The "electronic thermometer" for contact measurement is not fast for temperature measurement. Whether it is for underarms, oral cavity or anus, it is relatively uncomfortable, but fortunately it is not that difficult to operate and is easy to measure accurately. But it will also be affected by the environment, such as interference from nearby electromagnetic fields, so don't take your body temperature and play with your phone next time.
Really, read the product manual carefully before using it.
Don't bother to read the manual to trouble yourself, because the operation of the electronic thermometer is not so complicated, and anyone can use it, but if you want to measure accurately, read the precautions of the manual carefully, learn it once, save trouble and use it.
What kind of thermometer do you have at home?