While the drain connection for a garbage disposal is nearly universal and fits standard sink drain holes of 3 1/2 to 4 inches, the size of the disposal unit itself is not. You must have enough space in the cabinet underneath your sink to accommodate the disposal's housing. A larger model may not fit in a compact cabinet or if the existing plumbing is arranged in an unusual way. Before buying a new garbage disposal, measure the available space under your sink. If you are replacing an old unit, it's often easiest to choose a new model of a similar size.

Never put glass in the garbage disposal. It can damage your disposal or eject shards of glass out of the disposal and cause injury. If you get broken glass in your garbage disposal, turn it off and cut the power from the breaker, use a tool like pliers or tongs to remove the glass, and use a wet-dry vacuum to remove the remaining glass pieces. If you can’t access the disposal safely, call a garbage disposal repair pro.

The two main negatives of garbage disposals are they are a safety hazard in homes with children, and they frequently encounter blockage issues. While they might be annoying to fix and monitor, garbage disposals can significantly lower your trash use and are a great way to dispose of organic waste. While there are negatives, the vast majority of homeowners acknowledge the positives are enough to install a disposal in their home. 

Garbage disposals can be considered bad for the environment due to their electricity usage, but good for the environment because they reduce the food waste sent to landfills. If everyone used a garbage disposal, it would tax the wastewater treatment facilities in that region, but if we had to choose one of the options, we’d say they are a net positive on the environment when used correctly.