text: Although NBS is easier and safer to handle than bromine, precautions should be taken to avoid inhalation. NBS should be stored in a refrigerator. NBS will decompose over time giving off bromine. Pure NBS is white, but it is often found to be off-white or brown colored by bromine.
  In general, reactions involving NBS are exothermic. Therefore, extra precautions should be taken when using on a large scale.