After 10 weeks of radio silence, the National Nurses United union is ramping up pressure on the D.C. Council to enact strict staffing mandates for hospitals. The California-based union launched a letter-writing campaign this week targeting all 13 council members and Mayor Vincent Gray. Friday, the union will hold a rally at 5:30 p.m. in front of the John A. Wilson Building. "We've been doing lots of outreach to the community over the last several months," said union organizer Ken Zinn. "We're now escalating that outreach to include the mayor and the District council to urge expedient action on the bill."