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DEP Home : Community Concerns : Construction and Noise
Download a Temporary Noise Waiver Form (PDF)Use this form to apply for a temporary noise waiver to allow after-hours and nighttime construction projects.
Questions about construction noise control:Phone: 311Email: askdep@montgomerycountymd.govQuestions about Noise Suppression Plans:311 (Steve Martin)To report a problem with construction noise call:311
As a construction worker, contractor, or engineer, you should be aware of how your activities are regulated under the Montgomery County Noise Control Ordinance. With careful planning and operation, it's possible to minimize potential noise disturbances from construction activities.
Virtually all potential noise sources that operate permanently or semipermanently can be designed or controlled to meet the receiving property line standard. Likewise, potential sources under human control, such as electronically amplified sound, can be designed to meet the ordinance requirements.
Noise from some construction activities, however, is difficult, if not impossible, to control to the receiving property line. This is because the engineering design and technical controls that are effective on permanent stationary sources aren't practical or reasonable for a temporary, often mobile, noise source or combination of sources. The Noise Control Ordinance, therefore, contains certain standards specific to construction noise. DEP has several tools available to help mitigate and regulate this potential source of disturbance.
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The Montgomery County Noise Control Ordinance defines construction as temporary activities directly associated with site preparation, assembly, erection, repair, alteration, or demolition of structures or roadways. Construction noise levels must be measured on a receiving property, but no closer than 50 feet from the noise source.
From 7 a.m. to 5 p.m. weekdays, construction noise levels must not exceed:
At all times other than 7 a.m. to 5 p.m. weekdays, the general ordinance standards in the Noise Control Ordinance must be met. The following table provides a summary of the noise standards for construction activities:
7 a.m. to 5 p.m. (exempted hours) 75 dBA (85 dBA with a Noise Suppression Plan) 75 dBA (85 dBA with a Noise Suppression Plan)
5 p.m. to 9 p.m. (daytime hours) 65 dBA 67 dBA
9 p.m. to 7 a.m. (nighttime hours) 55 dBA 62 dBA
9 a.m. to 9 p.m. (daytime hours) 65 dBA 67 dBA
9 p.m. to 9 a.m. (nighttime hours) 55 dBA 62 dBA
*In most circumstances in the County, the receiving property will be considered residential.
** The U.S. Office of Personnel Management has a list of federally recognized holidays.
Be Aware! Construction activities are also subject to the "Noise Disturbance" provisions of the ordinance. Although a noise disturbance, as defined by the ordinance, could conceivably occur at any time, it is most likely to happen during nighttime hours. The following are examples of noise disturbances:
The County mails copies of the revised ordinance upon request. If you have questions or comments, contact the Office of Environmental Policy and Compliance at 311.
In addition to the Noise Control Ordinance, DEP has several mechanisms for controlling and regulating construction noise.
A Noise Suppression Plan is a written plan to use the most effective noise-suppression equipment, materials, and methods appropriate and reasonably available for a particular type of construction.
Several construction activities, such as pile driving and hoe ramming, might inherently exceed 75 dBA, depending on the circumstances. In those cases, the Montgomery County Noise Control Ordinance allows up to 85 dBA, provided a Noise Suppression Plan, approved by DEP, is implemented. Essentially, these plans require the best reasonably available control technology or strategy. They might involve equipment selection, scheduling, and temporary noise control devices to block or absorb the sound.
Read the full text of the Montgomery County Noise Suppression Plan Guidelines (PDF, 1pp, 497K) to learn more.
Occasionally, public works construction projects are done during hours that fall outside the County-designated normal construction hours of Monday through Friday 7 a.m. to 5 p.m. These projects are usually done in response to directives by state and local agencies to address traffic congestion and pedestrian safety issues. The Montgomery County Noise Control Ordinance allows for the issuance of a Temporary Noise Waiver to allow after-hours and nighttime construction projects if the benefit to the public offsets the noise the event will create in excess of the established limits. Refer to the application form and fee schedule below, and allow 30 days for the processing of your Temporary Noise Waiver application.
The following fees apply for exemption applications:
Residential, single-family $50 $100
Construction (all types private) $350 $350 + ($25 per source/site) $500
Industrial $350 $350 + ($25 per source/site) $500
Government $350 $350 + ($25 per source/site) $500
View a "Noisy Sites" map of the County showing active nighttime construction projects with approved noise waivers, or check the issued temporary noise waivers listed below:
Useful tips from learned from previous construction projects include the following:
Proactive and reasonable control of construction noise results in more content communities and successful, on-schedule projects with a minimum of hassle due to noise. It also removes the inconvenience of civil penalties, abatement orders, or stop work orders.
Noise emissions from all mechanical equipment must be expressed, in A-weighted decibels (dBA), measured at a stated reference distance. It's your responsibility to calculate the estimated sound intensity (in dBA) to ensure that it complies with the Montgomery County Noise Ordinance. The following guidance can help you:
These estimations are especially useful in determining equipment or facility placement (e.g. loading docks), or in the design of engineering controls. All calculations and assumptions should be submitted to the reviewing authority.
Note: Most equipment manufacturers, and especially those who produce or market in Europe or Asia, have detailed noise performance specifications for their products.