Asthmometer, pulsometer and tachymeter scale
Graduations on the dial or bezel from which different measures can be read.
- A tachymeter scale measures the speed of a moving object over a given distance in kilometres, miles or other unit.
- A telemeter scale measures the distance between an observer and a visible and audible event based on the speed of sound through air (approx. 340 metres/second).
- A pulsometer scale measures the number of heartbeats per minute and is usually graduated for 30, 20 or 15 heartbeats.
- An asthmometer scale measures the number of respirations per minute, usually on a scale of 15, 20 or 25 respirations.
- A productometer scale measures the number of items produced per hour, provided that each one takes no more than 60 seconds to make.
A watch can feature numerous combinations of scales, the most frequent being telemeter with tachymeter.