Washington State Ferries is enrolling its operations in Green Marine, the leading North American maritime industry environmental certification program.

“We are pleased to join Green Marine and look forward to working with its framework and team as part of our constant efforts to green our fleet and facilities,” Kevin Bartoy, WSF’s environmental program manager, said in a statement.

With 22 vessels, 19 terminals, and one maintenance facility, WSF is the largest ferry system in the country, and the first U.S. ferry operator to join Green Marine.

Green Marine’s environmental certification program guides ship owners, port authorities, terminal operators, and shipyard managers toward reducing their environmental footprint. The program addresses environmental issues including greenhouse gases, air emissions, oily water, underwater noise, spill prevention, and waste management.

“WSF is a sustainability leader when it comes to marine mammal protection and electric hybridization, for example, and there’s no doubt that WSF’s participation will help Green Marine to achieve its objective of advancing environmental excellence within the North American marine industry,” said David Bolduc, Green Marine’s executive director.