Managing Community Noise

 

Reasonableness

 

A basic premise of all noise complaints is “reasonableness”.  People are most accepting of noise that is reasonable. Here are several of many possible examples of how reasonableness affects our perceptions:

 

• Vehicles make noise in order to generate movement;
• Heating, ventilation and air conditioning (HVAC) equipment makes noise in order to bring us comfort in our buildings;

• Children make noise when they are having fun and using recreational areas;

• Tools make noise in order to produce work, and
• Construction activity makes noise in order to create and maintain infrastructure and buildings, including our homes.

 

Reasonableness is one of the primary factors that people use when tolerating or complaining about noise; and reasonableness is subjective. It makes common sense to tolerate reasonable sounds and not tolerate unreasonable ones. Even reasonable sounds which are commonly tolerated are considered noise, but unreasonable sounds are universally considered to be unwanted and intolerable.

 

Many factors are involved in our individual determinations of reasonableness. These are the components that vary by person and perspective. They often include opposing perspectives. Two core opposing perspectives are:

 

1. The producer of noise versus the receptor of noise. The receptor is the entity that hears the sound but has no connection except proximity, and
2. The benefactors of the noise versus the no benefit receptors. The receptor receives no benefit from the systems or devices that make the noise. They do not use those devices or do not have a connection to the systems/industries.

 

The reasonable determination is fundamentally why noise management has be assigned for communities to decide. It becomes so personal that the agreement on a national scale or even on a state level has become unreasonable by itself. This is a fundamental premise in our country’s history of tackling community noise management and why the EPA agency on community noise was defunded and forced into oblivion.

 

Implementation

 

Community based environmental noise management follows two general approaches:

1. Decibel-based noise criteria that restrict sound emission levels, and
2. Subjective "public nuisance/disturbance” noise standards which do not require the use of sound level meters for enforcement.

 

Decibel-based noise criteria provide a definitive scale to enforce noise emissions.

 

Positive aspects of decibel based criteria include:

1. Fixed impact thresholds that are well suited for design standards;
2. They are less likely to experience legal challenges of interpretation of what defines a noise violation, and
3. They provide a less subjective means for assessing noise impacts that doesn’t rely on personal interpretations.

 

Negative aspects of decibel based criteria include:

1. If the criteria levels are too high; people will be annoyed without recourse;
2. If the criteria levels are too low; projects and activities will be excluded;

3. Reasonableness cannot be defined by decibel criteria because reasonableness is subjective and decibel criteria are not;

4. Fixed criteria levels do not allow for flexible implementation which can be very important as issues change within a community;

5. Fixed criteria levels can become a shield if nuisance complaints become an issue;
6. Municipal enforcement can be an issue since complex instrumentation and trained personnel are necessary, and
7. Project permits may require expensive noise studies to demonstrate that compliance can be achieved and that money could be better used for buying quieter equipment and better equipment design. No noise study can prevent future noise impacts from occurring; predictions are not always accurate.

 

Nuisance noise ordinances provide a flexible means to enforce noise complaints. Public nuisance noise ordinances are typically based on subjective standards which always come down to reasonableness. A common definition is a noise condition that is objectionable to one or more reasonable persons.

 

Positive aspects of nuisance based criteria include:

1. Flexible emission standards that focus on the reasonableness of the sound emissions versus fixed levels;
2. Ease of implementation during permitting putting the onus on the project to not create future noise impacts and resolve them if they arise;
3. Nuisance criteria are easier for non-acoustically trained personnel to enforce. Enforcement can often be made through citizen witnesses without the need for rigorous measurements;
4. Noise can be tolerated in areas that are not sensitive and regulated in areas that are, and
5. Noise management can evolve with the community’s needs and desires.

 

Negative aspects of nuisance based criteria include:

1. The project has to create its own sound emission design standards;
2. They may be difficult to apply consistently and enforce when they are challenged;
3. They are a more subjective means for assessing noise impacts that rely on personal interpretations, and
4. Subjective criteria are more easily be challenged in court.

 

Audibility and Annoyance

 

It is important to note that the “threshold of audibility” is not necessarily a noise impact. Although being able to notice something by its faint sound may evoke annoyance, that annoyance is not due to excessive sound. It is reasonable to assume that faint sounds can evoke very strong negative feelings that even cause distress but that’s when the issue becomes more than acoustical. Exceptions could include unusual sounds, including tones, that may be inappropriate during hours when people are most noise sensitive, such as when sleeping.

 

At residential locations with low or moderate noise exposures, sound masking by other sounds does not exist and specific sounds can easily be noticed. The human ear is a very good hearing device and can distinguish and localize on sounds with 10 to 100 (10-20 dB) times less energy than the average ambient sound during quiet times. Noise, by definition, is considered unwanted sound, which is a subjective interpretation of a sound.

 

The “threshold of audibility” is when a person becomes aware of the sound. At this threshold, sometimes it is the cause of the sound which triggers annoyance versus the sound itself. The sound level is not high enough to create an adverse sound impact in a reasonable person but the association with the noise producing activity is the trigger for annoyance. A good analogy would be the noise generated by a mosquito; the sound level could hardly be considered a noise impact but the sound represents the presence of a potential parasite and therefore triggers a high level of annoyance. If audibility is considered a noise impact we should question if the activity should be present versus is the sound too loud.