Participants' walking speeds were measured in a smoke-filled section, as well as in a smoke-free section, of the tunnel.
Norway's restaurants and bars are already meant to have smoke-free sections where air does not circulate from smoking areas.
The City Council on Tuesday agreed to work toward a smoking ban for all new apartment units, and eventually, creating smoke-free sections for existing multi-unit buildings.
Councilman Rafi Manoukian said apartment owners can create smoke-free sections voluntarily.
They can copy Pasadena and ban smoking in all multi-unit buildings — but give owners time to comply — or require apartment buildings to have smoke-free sections.
Several council members have instead said in interviews this week that they would prefer to require apartment owners to create smoke-free sections within their buildings.
Councilwoman Laura Friedman said she'd also like to review an option where buildings of a certain size have smoke-free sections, adding that she's received a slew of complaints from tenants upset about second-hand smoke.
Some restaurant guides now have sections devoted to nonsmoking options; Zagat's 2002/2003 Paris guide, for example, lists more than 300 restaurants with nonsmoking sections; those with asterisks are completely smoke free.
Five ways to stay smoke free.
The museums are a smoke free zone, including outside spaces.
