A clinical thermometer cannot be used to measure huge temperatures because it had been designed to measure only human body temperature which varies over a short range. The clinical thermometer has a range of 35C to 42C. If we use it to measure high temperature, it may break and mercury present in the clinical thermometer is harmful.
A Laboratory thermometer is used to measure high temperatures and it does not have a kink, so mercury falls on its own, so it is not convenient to measure the temperature of the human body.
Some of the learners also asked: Why is laboratory thermometer not suitable for measuring human body temperature?