The PNSN is part of the Advanced National Seismic System (ANSS), and exchanges real-time data with adjoining networks. Equipment is operated at over 200 remote sites, and data is exchanged with other networks, including the US National Network.
Network sites are located in U.S. National Forests, on lands managed by the U.S. Bureau of Land Management, the Washington State Department of Natural Resources, and the Washington Dept. of Parks and Recreation, in schools and public buildings; or on private properties. Some sites have individual formal land-use agreements with the UW, other sites are covered by agreements with PNSN's cooperating institutions or funding agencies. Agreements generally include the right to maintain equipment on the site and the support of access. Some site fees are paid. Most sites consist of seismic monitoring equipment with little human presence. The network is dynamic and changes somewhat from year to year.
The data recording system, EARTHWORM, is a nationally standardized seismic data recording and exchange system. EARTHWORM allows data to be collected at local nodes and then broadcast to other nodes. The PNSN operates several local nodes, and exchanges data with adjoining networks through EARTHWORM systems.