What is the first step in measuring oral temperature?

Measuring oral temperature is a common practice in assessing a person's body temperature, and placing the tip of the thermometer under the tongue is indeed the correct first step in this process. The mouth is a suitable site for measuring temperature because it provides a good approximation of the body's core temperature.

When the thermometer is positioned under the tongue, it is surrounded by blood vessels that allow for a quick and accurate reading. For the oral method to be effective, the individual should be instructed to keep their mouth closed to ensure that the temperature reading is not affected by external factors, such as breathing through the mouth or the consumption of hot or cold foods and beverages just before the measurement.

The other methods mentioned, such as placing the thermometer in the armpit, inserting it into the anal canal, or placing it in the ear canal, serve as alternative routes for measuring body temperature but are not the first step in oral temperature measurement. Each of these methods has its specific procedures and contexts in which they are used.