Protection Level: It provided protection against larger droplets, but was less effective against smaller, airborne aerosol particles that could travel further than 6 feet.

Contextual Effectiveness: The rule was most effective when combined with other measures, such as masking and improved ventilation.

Evolution of Guidelines: Research indicated that in school environments, 3 feet of distancing, combined with masking, was as effective as 6 feet in preventing the spread of COVID-19.