June 29, 2012 > Fireworks - where can you use them? Fireworks - where can you use them? Dublin, Newark and Union City are the only cities in Alameda County where fireworks are allowed. Newark - Yes, "Safe and Sane" fireworks only. Only allowed between midnight June 30 and midnight July 4. Residential areas only. All parks close at 7:30 p.m. on July 4. (Newark municipal code 15.32.050.3302.8.1) Union City - Yes, "Safe and Sane" fireworks only. Only allowed between 8 a.m. to 10 p.m. on the days fireworks are sold (July 1-3); on July 4 from 8 a.m. to 11 p.m. All parks close at 7:30 p.m. on July 4. Not allowed: on public streets, City-owned buildings/land/parks, within 10 feet of a residence, or east of Mission Blvd due to high fire danger. Must have written approval from property owner if not on your own property. (Union City municipal code 15.20.210)