During the initial stages of the global COVID-19 pandemic, Prism conducted building operation assessments for 10 buildings managed by BentallGreenOak in the Greater Vancouver region. The intent was to mitigate COVID-19 transmission based on established engineering practices and the most up to date ASHRAE guidelines. Based on preliminary findings, a summary of remedial actions was provided to the operators to get their buildings in line with the recommendations in place at the time. Following the implementation of these recommendations and validation, verification letters were provided to the tenants. By enhancing the standards of their ventilation systems, BentallGreenOak gained confidence that they were operating systems according to established engineering practices.