In there any route for one who has passed 2 year graduation course from Bengal for doing MSc in chemistry. Can anybody help

UGC in 1992 said that for doing MSc one has to pass three year graduation course. But those who have passed earlier to that say in 1984, do they have any route for doing MSc in Chemistry / Maths and so forth if they are teachers teaching for last 5 to 10 years.