TE-BC251 NIOSH Bioaerosol Cyclone

Developed by the National Institute for Occupational Safety and Health (NIOSH) and manufactured by Tisch Environmental, the TE-BC251 is a wearable multi-stage bio-aerosol collector used for the collection of airborne viruses including INFLUENZA and COVID-19. This high quality, low cost cyclone is well suited for quick deployment to respond to the current rapidly evolving climate.  The multi stage cyclone is designed to trap bio-aerosols in one of three compartments for accurate retrieval of samples at multiple cut points.

At 3.5 l/min, the BC 251 conforms to the ACGIH/ISO criterion for separation of respirable and non-respirable airborne particles, which is widely used in health-related aerosol measurements. The BC 251 has been successfully used to collect airborne influenza virus in healthcare facilities and from the coughs of influenza patients. The sampler can be operated with commercially-available personal air sampling pumps.


Each sampler comes with the following:

  • (1) BC251 Cyclone
  • (1) Heavy Duty Carrying Case
  • (2) Falcon™ 15 mL Conical Centrifuge Tubes
  • (2) Fisherbrand™ Nonsterile Threaded End Microcentrifuge Tube without Caps
  • (2) Fisherbrand™ Colored Screw Caps
  • (1) Jar of O-ring grease
  • (10) TE-BC251-5 EPDM O-Ring, 1/16 Width Dash Number 027
  • (1) Filter Cassette
flow rate
1st stage 50%
cut-off size (um)
1st stage
standard deviation)
2nd stage 50%
cut-off size (um)
2nd stage
standard deviation)
2 4.9 1.48 1.7 1.68
3.5 4.1 1.51 1.0 1.59
10 2.1 1.44 0.41 1.56