The Department of Ecology (Ecology) is required to adopt maximum noise levels permissible in identified environments to protect against adverse effects of noise on the health, safety, and welfare of people, the value of property, and the quality of the environment.  In doing so, Ecology must also take into account the economic and practical benefits to be derived from the use of various products, whether the source of the noise or the use of such products in each environment is permanent or temporary in nature, and the state of technology relative to the control of noise generated by all such sources of the noise or the products.

A local government may impose limits or control sources differing from those adopted or controlled by Ecology.  Noise limiting requirements of local governments which differ from those adopted or controlled by Ecology must be approved by Ecology.  If Ecology fails to approve or disapprove the standards within 90 days, the standards are considered approved.

Ecology has adopted the following noise limitations for use by local governments:

• in a residential area, the maximum allowed amount of noise coming into the property is 55 decibels using the A filter (dBA) from a residential area, 57 dBA from a commercial area, and 60 dBA from an industrial area;
• in a commercial area, the maximum allowed amount of noise coming into the property is 57 dBA from a residential area, 60 dBA from another commercial area, and 65 dBA from an industrial area; and
• in an industrial area, the maximum allowed amount of noise coming into the property is 60 dBA from a residential area, 65 dBA from a commercial area, and 70 dBA from another industrial area.

Between the hours of 10 p.m. and 7 a.m., the noise limitations must be reduced by 10 dBA for receiving property within residential areas.

At any hour of the day or night, the noise limitations may be exceeded for any receiving property by no more than:

• 5 dBA for a total of 15 minutes in any one-hour period;
• 10 dBA for a total of 5 minutes in any one-hour period; or
• 15 dBA for a total of 1.5 minutes in any one-hour period.

Local noise ordinances may have different maximum dBA levels.  When a local noise ordinance is different, those are the standards and limits that apply.

Any person who violates a rule adopted by Ecology is subject to a civil penalty not to exceed $100 imposed by the local government.  This penalty provision does not preclude enforcement of any provisions of a local government noise ordinance.

A provider of essential services may exceed an allowable noise level established by a local government by up to 10 dBA, but not to exceed a maximum noise level of 80 dBA as measured by a sound level meter.

Ecology may also allow for noise limitations to be exceeded for any receiving property by no more than:

• 5 dBA for a total of 15 minutes in any one-hour period;
• 10 dBA for a total of 5 minutes in any one-hour period; or
• 15 dBA for a total of 1.5 minutes in any one-hour period.

Essential services include the provision, repair, or delivery of utility, telecommunications, food, water, or sanitary services.

Receiving property is real property within which maximum permissible noise levels may not be exceeded from sources outside the property.

Noise complaints related to the provision of essential services must be investigated by the local government, measured with a sound level meter from the complainant's receiving property by the local government, and reported by the local government to Ecology.

If a provider of essential services is found to have violated the noise standards, the provider of essential services must submit a noise management and mitigation plan to Ecology and the local government for the individual location found to be in violation.

A provider of essential services that fails to comply with noise standards on three or more occurrences, during any 12-month period, must install equipment to monitor noise levels at the individual location.

A provider of essential services that fails to comply with noise standards on six or more occurrences, during any 12-month period, may be subject to local government noise laws, regulations, and ordinances.