What type of weights shpould you not use if your goal is to build muscle mass

I believe that you shouldn't use low intensity (light weights) if you want to build muscle mass.
These types of weights won't help you much define the muscles you want to have, as opposed to free weights, weight machines, and high intensity (heavy weights) which definitely will. So if your goal is to build muscle mass, avoid light weights. 

The administration should take action.