4.24.3000
Persons rendering emergency care or transportation – Immunity from liability – Exclusion. Any person, including but not limited to a volunteer provider of emergency or medical services, who without compensation or the expectation of compensation renders emergency care at the scene of an emergency or who participates in transporting, not for compensation, therefore an injured person or persons for emergency medical treatment shall not be liable for civil damages resulting from any act or omission in the rendering of such emergency care or in transporting such persons, other than acts or omissions constituting gross negligence or willful or wanton misconduct. Any person rendering emergency care during the course of regular employment and receiving compensation or expecting to receive compensation for rendering such care is excluded from the protection of this subsection.
Automatic External Defibrillator:
A person or entity who acquires a defibrillator shall ensure that:
A person who uses an AED at the scene of an emergency and all other persons and entities providing services under this section are immune from civil liability for any personal injury that results from any act or omission in the use of the AED in an emergency setting. The immunity from civil liability does not apply if the acts or omissions amount to gross negligence or willful or wanton misconduct.
http://aiawa.org/wp-content/uploads/2013/10/aiawa-disaster-good-samaritan-wa.pdf
https://app.leg.wa.gov/rcw/default.aspx?cite=70.54.310