Special Maintenance Considerations - Effective Building Maintenance: Protection of Capital Assets - page 117

Table 4-10. Filter Application Guide lines
(Adapted from ASHRAE Standard 52.2-2007)
the low end of the MERV scale, despite claims by the manufacturers that
this type of filter is both effective and reliable. The standard recognizes
that these claims are, at best, exaggerated and the filters do not perform
well or reliably in HVAC systems.
“Active” electrostatic or electronic filters are very efficient, with
an MERV of 12-15, when they are properly operated and maintained .