Changing Engineering Specialisations after Undergrad
In general, it is possible to switch disciplines within engineering between the bachelor's and master's programs. 

However, this does depend a lot on the nature of the programs and how closely related they are. For instance, it's probably easier to go from chemical to biomedical engineering than it is to electrical or civil. 

It's also worth pointing out that you may need to take additional coursework that candidates with a degree in the discipline do not.