So why are they telling people to sanitize surfaces, block their coughs etc? If it could not spread outside of cells then it would not spread at all since the minute it leaves your body (coughing etc) it would no longer be contagious.
When a new pathogen wreaks havoc on the planet, scientists from across the globe race to understand how it behaves and spreads. Now, scientists have found that the novel coronavirus (2019-nCoV) can survive on metal, plastic, and glass for as long as nine days.
www.news-medical.net
There are probably factors that can alter this time. Certain lab equipment like incubators for example can keep them alive for much longer for research purposes. Those conditions could technically happen outside of a lab.
What will be interesting is to see if it can be carried via insects such as mosquitoes once those start coming out. If it turns out it can, summer might be quite a doosey this year.