Masks are once again required in the nation’s capital while indoors. The mandate comes on the heels of new Center for Disease Control and Prevention guidance, which urges everyone in locations of substantial or high COVID-19 transmission to wear masks inside — all to limit the spread of the highly contagious delta variant. This week we talk to WTOP’s Mike Murillo and John Domen about the nuts and bolts of D.C. ‘s mask mandate and what this resurgence of the coronavirus means for the greater Washington region.