Characterizing Particulate Generation During Cardiopulmonary Rehabilitation Classes With Patients Wearing Procedural Masks

Scott A. Helgeson, Bryan J. Taylor, Kaiser G. Lim, Augustine S Lee, Alexander S. Niven, Neal M. Patel

Research output: Contribution to journalArticlepeer-review


Background: The clinical benefits of cardiopulmonary rehabilitation are extensive, including improvements in health-related quality of life, emotional condition, physical function, and overall mortality. The COVID-19 pandemic continues to have a negative impact on center-based cardiopulmonary rehabilitation. Justifiable concern exists that the exercise-related increase in pulmonary ventilation within the rehabilitation classes may lead to the generation of infectious respiratory particles. Research Question: Is cardiopulmonary rehabilitation while wearing a procedural mask a particle-generating procedure? Study Design and Methods: Data were collected prospectively at a cardiopulmonary rehabilitation facility with all patients wearing a procedural mask. Small (0.3-4.9 μm) and large (5-10 μm) particle generation was quantified using a light-scattering particle counter. Data were analyzed by time, exertion level, and number of participants. Results: A total of 24 distinct patients attended two or more of the cardiopulmonary rehabilitation classes tested. Most of the patients were men (n = 16 [67%]) and were in rehabilitation because of cardiac disease. During the cardiopulmonary rehabilitation class, small and large micrometer-size particles increased with increasing class size. In classes with four patients or more, a significant increase was found from ambient levels in both small (four patients, P < .01; and five patients, P < .01) and large (four patients, P < .01; and five patients, P < .01) particle count that peaked at about 35 to 40 min during each class. Interpretation: Using an airborne particle counter, we found significant exercise-related increases in both small and large micrometer-size particle generation during cardiopulmonary rehabilitation classes, with larger class sizes (ie, more patients), despite participants wearing a procedural mask.

Original languageEnglish (US)
Pages (from-to)633-641
Number of pages9
Issue number2
StatePublished - Aug 2021


  • aerosol
  • cardiopulmonary rehabilitation
  • coronavirus
  • particle generation
  • particle measurement

ASJC Scopus subject areas

  • Pulmonary and Respiratory Medicine
  • Critical Care and Intensive Care Medicine
  • Cardiology and Cardiovascular Medicine


Dive into the research topics of 'Characterizing Particulate Generation During Cardiopulmonary Rehabilitation Classes With Patients Wearing Procedural Masks'. Together they form a unique fingerprint.

Cite this