hello aspirant,

there is no subject in gate exam on health safety and environment. and in india there is not many colleges which offers this course. you can check gate official website. i have provided the link below-

http://gate.iitd.ac.in/syllabi.php

however you can done your mtech in health safety and environment from UPES. you need atleast 60% marks in btech.

https://www.upes.ac.in/course/mtech-health-safety-environmental-engineering