Many producers indicates this short time duty only in the instruction handbook of the device, other indicates it on the very device.

The concept of short time duty is easy to understand when referred to human beings in medical applications both somatic (body) as well as psychological (mind).

The short time duty (or short time operation) indicates an operating mode of increased performance but for a shorter length of time.

A last good example are allergies: in this case the load is the concentration of the allergic substance and the short time duty is depending on many factors like age, genetics, medical condition and so on.

The analogy with devices is useful to better understand both type of applications and should not be underestimated as if human beings were much better than their machines or devices: in this case a short time duty prevents from diseases.

Only by psychological aspects the short time duty is very different from human being to human being depending on their culture and religion (to sneeze in a far east country will rapidly irritate the companionship while just causing commiseration in a west country).

Another simple example of well defined short time duty are the exposure times of sunscreen lotions (in this the case the load is also the electromagnetic radiation dose but its energy is just weaker and its frequency is shorter, i.e. ultra-violet light UV).