The Spanish Association for Standardisation and Certification (AENOR) has, among other obligations, that of establishing what characteristics measurement devices should possess and how they should be handled.
The standards for measurements in Spain are called UNE standards.

There are a great variety of UNE standards: almost everything has been provided for, from what the speedometer that measures the velocity of a vehicle has to be like, to what the slides in swimming pools have to be like so that they are not dangerous.

The UNE standards related to Physics indicate how, and with what, to measure different magnitudes. They are protected by the rules for intellectual property, so that in order to see them the corresponding charge must be paid. There is an AENOR publication which details the current norms in force: here.

The box below has a link to an AENOR search form. Introduce a key word/title, for example "thermometers", observe the large number of specifications which exist for the various types of thermometres.

Carry out other searches which interest you. The terms "pendulum" and  "cd" could be good examples.