Effect of noisy ceiling fans in auditorium, conference rooms and meeting halls in India 

A typical classroom has approximately 40+ students and a teacher who communicates through voice. In India, ceiling fans are mostly used for the thermal comfort of the occupants in the classroom. Ceiling fans are the best solution in this scenario as they are simple, cost-effective, healthy, and efficient. But typical ceiling fans are noisy, and it becomes a significant problem in a setting like a classroom, meeting room, auditorium, where the occupants are primarily expected to listen from a speaker. 

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A regular noisy ceiling fan generates a noise level around 59 dBA. A typical classroom may have about 5 fans, which would be a noise source of about 66 dBA. The noise level in dBA is a logarithmic scale so adding a fan can be roughly estimated to increase the noise by 3 dBA. 

Human voice sound levels range from 30 to 80 dBA. 

Human Voice	Sound level (dBA)
Casual	37
Normal	44
Raised	53
Loud	63
Shouted	75

As per the table above in order to be heard, the speaker (teacher) must be ‘Loud’ or ‘Shout’. With the addition of more fans to the room, the speaker will inevitably require some amplifiers to be clearly audible.  

Many classrooms may not have the sophistication to have amplification systems nor it is advisable to lower the thermal comfort (reducing the ceiling fan speed) of a semi-closed room with many occupants. 

Superfan’s Super Q silent ceiling fans are 2 times quieter than regular fans at 49 dBA. A combination of 5 Super Q ceiling fans would generate a noise of 56 dBA only compared to 66 dBA. A difference of 10 dBA is 2 times quieter in terms of human perception. 

When using Super Q in a classroom, the speaker (teacher) can lower their voice to a level less than ‘Loud’ while the occupants enjoy the same (or better) thermal comfort. 

Fan type	1 fan	2 fans	5 fans	8 fans	10 fans
Regular fan noise level (dBA)	59	62	66	68	69
Human voice required to be heard	Loud	Loud	Shout	Shout	Shout
Super Q noise level (dBA)	49	52	56	58	59
Human voice required to be heard	Raised	Raised	Loud	Loud	Loud

All these measured values are for airflow of 230 CMM from a 48” ceiling fan at a level greater than 7 feet below the fan. These values have been measured at FCRI, Kerala, India. 

Reference: 

*Speech and Noise Levels Associated with Meeting Rooms Bradley, J. S.; Gover, B. N.