Keith Oswald, the district’s chief of equity and wellness, explained to the board that there are four metrics that must be met in order for masks to be optional on campus: when COVID-19 vaccines are available to children between 5 and 11 years old; when the weekly average number of new COVID-19 cases are below 50 per 100,000 people; when the weekly COVID-19 positivity rate stays below 8%; and when both of those weekly numbers remain at those “moderate” levels for four weeks.