In April 2009, Washington enacted S.B. 5136, restricting homeowner's associations from prohibiting the installation of solar energy panels. A homeowner's association may issue guidelines related to visibility and aesthetic aspects of solar panel placement, but it may not prohibit a resident or owner from installing solar panels, provided that the solar panels meet certain criteria. Solar panels must meet local and state health and safety requirements. Solar water-heating systems must be SRCC certified (or certified by an equivalent national organization). Solar-electric systems must meet NEC, IEEE, and UL or other testing laboratory safety and performance standards.