The National Park Service announced that the use of e-cigarettes are banned where traditional smoking is already prohibited.
National Park Service Director Jonathan Jervis said that it is a step to safeguard people's health.
"Protecting the health and safety of our visitors and employees is one of the most critical duties of the National Park Service. We are therefore extending the restrictions currently in place protecting visitors and employees from exposure to tobacco smoke to include exposure to vapor from electronic smoking devices," said Jervis.
The memo to park service employees read that the new policy was introduced "out of an abundance of caution in light of the scientific findings and uncertainty to date, and in the interest of equity."
However, advocates of vaping are coming out against the new policy.
"Outdoor smoking bans in parks can at least somewhat be justified by the risk of fires, but vapor products pose no more of a fire risk than a cellphone battery," said, Gregory Conley, president of the American Vaping Association trade group.
"This behavior is shameful and any enforcement of the ban will constitute a great misuse of government resources. The National Park Service should leave ex-smokers alone and let them camp and hike in peace," said Conley.