  In recent years, universal scaling has gained renewed attention in the study
of magnetocaloric materials. It has been applied to a wide variety of pure
elements and compounds, ranging from rare earth-based materials to transition
metal alloys, from bulk crystalline samples to nanoparticles. It is therefore
necessary to quantify the limits within which the scaling laws would remain
applicable for magnetocaloric research. For this purpose, a threefold approach
has been followed: a) the magnetocaloric responses of a set of materials with
Curie temperatures ranging from 46 to 336 K have been modeled with a mean-field
Brillouin model, b) experimental data for Gd has been analyzed, and c) a
3D-Ising model ---which is beyond the mean-field approximation--- has been
studied. In this way we can demonstrate that the conclusions extracted in this
work are model-independent. It is found that universal scaling remains
applicable up to applied fields which provide a magnetic energy to the system
up to 8\% of the thermal energy at the Curie temperature. In this range, the
predicted deviations from scaling laws remain below the experimental error
margin of carefully performed experiments. Therefore, for materials whose Curie
temperature is close to room temperature, scaling laws at the Curie temperature
would be applicable for the magnetic field range available at conventional
magnetism laboratories ($\sim 10$ T), well above the fields which are usually
available for magnetocaloric devices.
