1). Particle Size:
It is a virus approximately 970 nanometers (.97 microns), HEPA Filtration Recommended.

2). Changing Filters in Specific Conditions:
Review Chapter 8 of the NAFA Guide to Air Filtration, 5th Ed., 2014 for information about when a HEPA should be changed given specific conditions.

3). Testing a HEPA In-place:
If a HEPA has not been in-place tested, it should be to ensure integrity, especially with something like Ebola as a risk factor.  Contact the Controlled Environment Testing Association (CETA) at www.cetainternational.org to locate a certifier near to you who can do this as part of your overall filter program.  This includes Biological Safety cabinets – units (NAFA Guide pages 10.8 – 10.10)

4). Training End-Users:
Filter Services of Indiana, Inc. offers a “Hospital Technician Certification Program” (NCT) that trains filter technicians to change filters correctly.  The tutorial includes the IOM book and the test.