Limit 45-75 dB, reality reaches 84 dB
Dhaka’s road noise is exceeding legal limits by as much as 31 decibels in some areas, with studies recording ambient noise of up to 84 dBA and individual vehicle horns reaching 121 dB, raising concerns over persistent traffic-noise violations and weak enforcement.
Dhaka’s roads routinely record noise levels far above the limits set under Bangladesh’s Noise Pollution (Control) Rules, 2006, with traffic congestion and frequent vehicle horns contributing significantly to the capital’s worsening noise pollution problem.
Under the rules, the permissible daytime noise level is 50 decibels (dB)
in silent zones, 55 dB in residential areas, 60 dB in mixed areas, 70 dB in commercial areas and 75 dB in industrial areas. At night, the limits are lower-40 dB, 45 dB, 50 dB, 60 dB and 70 dB respectively.
However, studies show that the reality on Dhaka’s roads is markedly different. A 2025 study published in Scientific Reports recorded a median sound level of 63 dBA across different locations in Dhaka, with readings ranging from 50.5 dBA to 84 dBA. The median level alone was above the daytime limit
for residential areas.
A 2024 study of noise pollution in five Dhaka areas found even higher levels during office hours. Noise reached 84 dBA in Tejgaon, 83 dBA in Motijheel, 84 dBA in Shiddeshori, 78 dBA in Azimpur and 76 dBA near Dhaka Medical College. Compared with the applicable limits used in the study, the recorded levels were 9 to 31 dB higher.
The difference was particularly striking around sensitive areas. Noise near Dhaka Medical College reached 76 dBA, against the study’s applicable daytime limit of 45 dBA a difference of 31 dB. In Azimpur, the recorded level was 78 dBA against a 50 dBA limit, while Shiddeshori recorded 84 dBA against a 60 dBA limit.
Vehicle horns can produce even higher short-term noise levels. A traffic-noise study at Shyamoli found average horn levels of around 99.8 dB for motorcycles, 98.3 dB for buses and 85 dB for private cars, while the maximum recorded bus-horn level reached 121 dB.
In another enforcement drive, the Department of Environment measured five vehicle horns on Manik Mia Avenue and found one producing 110 dB, while the other four registered between 97 dB and 101 dB.
Experts, however, caution that a vehicle’s horn reading and an area’s ambient noise level are not directly comparable. A horn reading measures the sound produced by an individual vehicle at a particular distance, while the legal limits generally refer to the overall noise level of an area. The measurement method, duration and location therefore matter when comparing the figures.
Traffic DC MD Rafiqul Islam told The New Nation that there are traffic laws, but many people do not properly follow them. Ambulances may use horns when necessary, but some use them without need, while motorcycles often use loud horns in residential areas.
“That is why fines are imposed on violators, and they are instructed to follow the rules properly.”
Dhaka’s traffic environment frequently exceeds the noise levels permitted for residential, mixed-use and sensitive areas.
A 2025 study found that only 1.9pc of daytime measurement minutes and 2.7pc of nighttime minutes across its Dhaka sites remained below the WHO guideline levels for traffic noise.
The persistence of excessive noise also raises questions about enforcement. Despite restrictions on loud and hydraulic horns and legal provisions against excessive noise, roadside measurements continue to show levels far above the permissible limits in different parts of the capital.
For Dhaka residents, therefore, the issue is not simply the occasional unnecessary honk. It is the cumulative impact of thousands of vehicles, repeated honking and heavy traffic on an already noisy urban environment.
The gap between the legally permissible limits and what residents experience on the streets suggests that controlling horn use alone may not be enough; stronger enforcement and broader traffic-noise management may also be needed.
