🎯 Why It Matters
Noise affects user comfort, regulatory compliance, and product marketability. Office equipment typically requires <40 dBA. Industrial settings may accept 60-70 dBA. Noise also indicates fan health — increasing noise often signals bearing wear.
📐 How to Read
dBA is logarithmic: 30 dBA = whisper, 40 dBA = quiet office, 50 dBA = normal conversation, 60 dBA = loud office, 70 dBA = vacuum cleaner. Fan noise scales with RPM — reducing speed by 20% can cut noise by 5-8 dBA.
📏 Typical Values
Ultra-quiet (medical/lab): 15-25 dBA. Office equipment: 25-40 dBA. Server/telecom: 40-55 dBA. Industrial: 55-70 dBA. Note: measurements at 1m distance in free field.
🔗 Related Parameters
Airflow, RPM, Bearing Type, Fan Size
❓ Frequently Asked Questions
How can I reduce fan noise?
1) Use larger, slower fans — a 120mm at 2000 RPM is quieter than a 60mm at 6000 RPM for the same airflow. 2) PWM control reduces speed at low load. 3) Rubber mounting gaskets isolate vibration. 4) Clean or replace clogged filters.
What causes fan noise to increase over time?
Bearing wear is the #1 cause. Sleeve bearings become noisier after 20,000-30,000 hours. Dust accumulation on blades unbalances the impeller. Loose mounting amplifies vibration.
Is dBA the only noise metric that matters?
No. Also consider tonal noise (specific frequencies that stand out) and sone ratings. A fan at 35 dBA with tonal whine may be more annoying than a fan at 40 dBA with smooth broadband noise.