Filters containing 300 g of activated carbon per 0.09 m2 of
filter face area were installed in two “experimental” filter banks within an office building
located in Sacramento, CA. The ozone removal performance of the filters was assessed
through periodic measurements of ozone concentrations in the air upstream and downstream
of the filters. Ozone concentrations were also measured upstream and downstream of a
“reference” filter bank containing filters without any activated carbon. The filter banks with
prefilters containing activated carbon were removing 60% to 70% of the ozone 67 and 81 days
after filter installation. In contrast, there was negligible ozone removal by the reference filter
bank without activated carbon