Determining removal efficiency of filter materials

A testing system, comprising:

• a first filter arranged to receive air and perform a first stage filtering of the air;
• a second filter in fluid communication with the first filter and arranged to receive air from the first filter after the first stage filtering is performed and to perform a second stage filtering of the air;
• a first sampling filter positioned between the first and second filters, arranged to receive the air that is effluent from the first filter after the first stage filtering is performed, and arranged for testing removal efficiency of the first stage filtering;
• a second sampling filter arranged to receive the air that is effluent from the second filter after the second stage filtering is performed and arranged for testing removal efficiency of at least the second stage filtering, the removal efficiency of the second stage filtering at least corresponding to a capability of the testing system to detect particles in the air that are smaller than a predetermined particle size;
• and
• a control system configured to determine the removal efficiency of the first stage filtering and the second stage filtering based at least in part on the collected particles and volumetric flow of air before and after the first stage filtering and the second stage filtering.

A method in a testing system, the testing system comprising a first filter associated with a first stage filtering, a second filter associated with a second stage filtering, a first sampling filter associated with a first efficiency of the first stage filtering, and a second sampling filter associated with a second efficiency of the second stage filtering, the method comprising:

• determining one or more of:
• a first volumetric flow of air associated with the first filter;
• a second volumetric flow of the air associated with the first and second filters;
• and
• a third volumetric flow of the air associated with the second filter;
• collecting first particles using the first sampling filter after the first stage filtering and second particles using the second sampling filter after the second stage filtering;
• and
• determining an efficiency of one or more of the first stage filtering and the second stage filtering based on one or more of the first volumetric flow, the second volumetric flow, the third volumetric flow, the first particles, and the second particles.