A report last month on reducing the noise of construction equipment ($2m fund to help firms get quieter construction equipment, March 12) and the National Environment Agency's (NEA) letter (NEA acts on contractors violating noise regulations, and not only when there are complaints, March 28) focused on the noise from construction activities, which is somehow inevitable.

However, not all noise emanating from construction sites is due to construction activity.

I have repeatedly complained to NEA and the Housing Board (HDB) about the humming noise emanating from the electrical generators for lighting and air-conditioners that can be heard from the HDB Sky Vista site in Bukit Batok, to no avail.

The noise is most disturbing and annoying, even as NEA claims that it is within the construction noise level of 55 A-weighted decibels at night.

NEA should not be basing this on the noise level specified in its construction noise control standards, as the humming noise could be prevented altogether if the site were connected to the main electricity grid.

Alternatively, NEA could mandate the use of lithium-ion storage batteries, which are used to provide power to 30,000 homes in South Australia.

Besides, the World Health Organisation guidelines' recommendation for community noise inside bedrooms relating to night-time sleep disturbance is 30 A-weighted decibels for continuous noise.

Also, the US National Institutes of Health has stated that "environmental noise has been linked to several non-auditory, biologically relevant health outcomes, including increased levels of hypertension and high blood pressure, lowered cognitive ability and an increased prevalence of cardiovascular disease".

NEA and HDB should not overlook the well-being of hundreds, if not thousands, of residents, leading to the loss of productivity and other deleterious health effects, for the sake of a few construction workers staying on the site.

Bin Hee Heng