  We investigate the impact of the delay in compulsory mask wearing on the
spread of COVID-19 in the community, set in the Singapore context. By using
modified SEIR-based compartmental models, we focus on macroscopic
population-level analysis of the relationships between the delay in compulsory
mask wearing and the maximum infection, through a series of scenario-based
analysis. Our analysis suggests that collective masking can meaningfully reduce
the transmission of COVID-19 in the community, but only if implemented within a
critical time window of approximately before 80 - 100 days delay after the
first infection is detected, coupled with strict enforcement to ensure
compliance throughout the duration. We also identify what is called a point of
no return, a delay threshold of about 100 days that results in masking
enforcement having little significant impact on the Maximum Infected Values.
