nPB to be classified as Hazardous Air Pollutant

The regulatory environment for nPB (n Propyl Bromide) is changing. February 4, 2022, nPB will be considered a hazardous air pollutant and with it reporting requirements will change – along with emission standards.

In light of these coming changes, it might be time to consider some of the following (from least difficult to more difficult):

  1. Consider validation testing of direct npb alternative solvents. There are nPB replacement solvents available that have similar cleaning and performance characteristics, that might make switching from nPB to a different solvent fairly easy (after test part cleaning evaluation) or other validation / sample testing.
  2. Upgrade your vapor degreaser. You can continue to use nPB if your vapor degreaser is NESHAP compatible – and thus enable you to continue vapor degreasing. If your vapor degreaser does not have the proper NESHAP require emission safeties – upgrading to one that does will be necessary.
  3. Consider different solvent chemistry. There are many cleaning solvents available that might be an alternative – that give you the same cleaning capabilities. The thing that was nice about nPB is that it evaporates quickly, is non-flammable, and has a high KB value for cleaning. If you are going to keep vapor degreasing, a non-flammable, azeotropic solvent will still be required…better vapor degreasing solvents are available.
  4. Consider water-based “Aqueous” cleaning. For many, leaving solvent cleaning behind will be a consideration. And this might be an option. Aqueous cleaning, although not as effective as solvent vapor degreasing can be a viable option for some.

With the nPB regulatory changes coming, those currnetly using or considering using nPB might start looking for alternative cleaning methods and solvents.

If you have questions about these changes and your options – feel free to call the solvent cleaning and vapor degreasing experts at 84.640.8923 or visit