HVAC Unit Sound Ratings

Indoor Air Quality Information

Interpreting the Sound Ratings of an HVAC Unit

Common Sounds

This decibel (dBA) table compares some common sounds and shows how they rank in potential harm to hearing. In many industries, workers are exposed to dangerous noise levels. This is particularly true in the construction, lumber, mining, steel and textile industries. Consider these volumes in context of your air conditioner replacement or furnace replacement or other heating system service or cooling system services.

SOUND	NOISE LEVEL (dBA)	EFFECT
Jet Engines (Near)	140
Shotgun Firing	130
Jet Takeoff (100-200 Ft.)	130
Rock Concert (Varies)	110-140	Threshold of pain (125 dB)
Oxygen Torch	121
Disco/Boom Box	120	Threshold of sensation (120 dB)
Thunderclap (Near)	120
Stereo (Over 100 Watts)	110-125
Symphony Orchestra	110	Regular exposure of more than 1 minute risks permanent hearing loss (over 100 dB)
Power Saw (Chain Saw)	110
Jackhammer	110
Snowmobile	105
Jet Fly-over (1000 Ft.)	103
Electric Furnace Area	100	No more than 15 minutes of unprotected exposure recommended (90-100 dB)
Garbage Truck/Cement Mixer	100
Farm Tractor	98
Newspaper Press	97
Subway, Motorcycle (25 Ft)	88	Very annoying
Lawnmower, Food Blender	85-90	Level at which hearing damage begins after 8 hours (85dB)
Recreational Vehicles, TV	70-90
Diesel Truck (40 Mph, 50 Ft.)	84
Average City Traffic Noise	80	Annoying; interferes with conversation; constant exposure may cause damage
Garbage Disposal	80
Washing Machine	78
Dishwasher	75
Vacuum Cleaner	70	Intrusive; interferes with telephone conversation
Hair Dryer	70	Intrusive; interferes with telephone conversation
Normal Conversation	50-65
Quiet Office	50-60	Comfortable (under 60 dB)
Refrigerator Humming	40
Whisper	30	Very quiet
Broadcasting Studio	30
Rustling Leaves	20	Just audible
Normal Breathing	10
	0	Threshold of normal hearing (1000-4000 Hz)

Since the sensitivity of the ear to sound is not the same for all frequencies, weighting or attenuating filters are included in the sound level meter’s circuits to simulate the ears’ response. A noise level meter gives an instantaneous measurement of the noise present, but cannot measure the duration of the exposure. To measure the amount of noise a person is exposed to over a period of time, a “dosimeter~ or an integrated sound level meter must be used. Sources for above include the American Medical Association and the Canadian Hearing Society of Ontario. Decibel table developed by the National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland 20892. January 1990.

If you have any questions about the sounds or volume being emitted by your HVAC equipment, just contact us and we can look into it. As a leading local HVAC company, we are always interested in our customers having a comfortable home environment.

Related Information

Understanding HVAC Unit Sound Ratings and Their Impact

When selecting an HVAC system, sound ratings are a critical factor, especially for those sensitive to noise or residing in areas with noise restrictions. The sound produced by HVAC units is measured in decibels (dB), and understanding these ratings can significantly influence your comfort and satisfaction with the system.

Decibel Levels and Their Implications

The decibel scale is logarithmic, meaning each increase of 10 dB represents a tenfold increase in sound intensity. Here’s a breakdown of common HVAC sound levels and their implications:

20-30 dB: Comparable to a whisper or rustling leaves, units in this range are considered extremely quiet. These are ideal for bedrooms, libraries, or any environment where silence is golden.
40-50 dB: Equivalent to the ambient noise in a library, units with these ratings are generally quiet enough for residential areas, providing a comfortable environment without causing disturbances.
60-70 dB: Similar to normal conversation or office noise, these units may be suitable for commercial properties or areas where noise is less of a concern. However, in residential settings, these might be noticeable and potentially disruptive.
80+ dB: Comparable to city traffic or a vacuum cleaner, systems in this range might require additional soundproofing measures if installed in noise-sensitive areas. Such noise levels can be intrusive and may not be suitable for residential use without modifications.

Factors Influencing HVAC Sound Levels

Unit Size and Type: Larger units or those with higher capacities often produce more noise. The size of your space and your specific heating or cooling needs should guide your choice. Smaller units with lower capacities may suffice for smaller spaces and generally produce less noise.
Installation Location: The placement of the unit can significantly affect perceived noise levels. Installing units away from windows, bedrooms, or common areas can help minimize disturbances. Consider placing outdoor units on a solid surface to reduce vibrations and noise transmission.
Maintenance and Age: Regular maintenance can reduce noise levels by ensuring all components function correctly. Over time, wear and tear can increase noise levels, so older units may become noisier. Routine inspections and timely repairs can mitigate this.
Technological Features: Modern HVAC systems often come equipped with noise-reduction technology, such as variable speed motors, insulated compressors, and advanced fan designs. These features can significantly lower sound levels, providing a quieter experience.
Building Design and Acoustic Properties: The design of your building can also impact how sound travels. Buildings with open layouts or hard surfaces may amplify sound, while those with carpets, curtains, and soft furnishings may absorb it, reducing overall noise levels.

Tips for Reducing HVAC Noise

Sound Barriers: Installing barriers or acoustic panels around the unit can help dampen noise. These barriers can be made from materials like foam, mass-loaded vinyl, or even dense vegetation.
Vibration Pads: Placing vibration pads under the unit can reduce noise caused by vibrations. These pads absorb vibrations and prevent them from transferring to the building structure.
Regular Maintenance: Keeping the system well-maintained ensures all parts are functioning smoothly, reducing noise. Regularly check for loose parts, worn bearings, and other potential noise sources.
Ductwork Insulation: Insulating ductwork can prevent noise from traveling through the ducts and into living spaces. This is particularly important for systems with long duct runs.
Professional Installation: Ensure your HVAC system is installed by professionals who are experienced in minimizing noise. Proper installation can prevent many noise issues from arising.

Case Studies and Examples

Case Study 1: Residential Quiet Zone

A family living in a suburban area sought to replace their aging HVAC system with a quieter model. They chose a unit with a sound rating of 25 dB, comparable to a whisper. By installing the unit in their basement and using insulated ductwork, they achieved a significant reduction in noise, creating a peaceful home environment.

Case Study 2: Commercial Office Space

A company operating in a shared office building needed an HVAC solution that wouldn’t disrupt their work environment. They selected a system with a sound rating of 45 dB and installed it with additional soundproofing panels. The result was a comfortable workspace where conversations and phone calls could occur without interference from the HVAC system.

Case Study 3: Urban Apartment Complex

An urban apartment complex faced complaints from tenants about the noise from the rooftop HVAC units. The management decided to upgrade to units with variable speed motors and sound blankets. These changes reduced noise levels to 60 dB, similar to normal conversation, significantly improving tenant satisfaction.

The Future of Quiet HVAC Systems

The HVAC industry continues to innovate, with manufacturers striving to create quieter systems without sacrificing performance. Future advancements may include:

Enhanced Soundproofing Materials: New materials that better absorb sound and reduce vibrations are continually being developed.
Smart Technology Integration: Smart HVAC systems can adjust their operation based on real-time noise levels, reducing sound output during quieter periods.
Eco-Friendly Designs: As sustainability becomes a priority, quieter units that also offer energy efficiency are likely to gain popularity.

Conclusion

Understanding HVAC unit sound ratings and their implications is crucial for making an informed decision that balances comfort, performance, and noise levels. By considering factors such as unit size, installation location, and technological features, you can select a system that meets your needs while maintaining a peaceful environment. For personalized advice, feel free to contact our team, who can assist you in finding the perfect HVAC solution for your home or business.