Cascade impactors are used to capture 0-10μm particles. The combination of cascade impactor with nasal spray expansion chamber is used to measure fine particle dose of drugs in nasal sprays and nasal aerosols.

1L capacity: used in nasal aerosols to maximize deposition below the top stage.

2L capacity: used in nasal sprays to maximize nebulization and deposition.

5L capacity: for some stronger nasal sprays, additional room is required to be able to generate aerosol plume.

FDA Bioavailability and Bioequivalence Studies for Nasal Aerosols and Nasal Sprays for Local Action (2003)

FDA Nasal Spray, Inhalation Solution, Suspension & Spray Drug Products（2002）

Nasal Preparations (Dosage Forms 0676) Ph.Eur. 2021 10.5