The National Environment Agency (NEA) has conducted two rounds of thermal fogging in Aljunied Crescent/Sims Drive since a Zika cluster was identified there last week.
But while thermal fogging kills adult mosquitoes, some residents have raised concerns over how safe it is for humans.
But Mr Thomas Fernandez, chief executive at PestBusters, said residents have little to worry about.
While people outside should avoid an area undergoing thermal fogging, those at home can just close their windows.
In assuring the public that thermal fogging was safe in a Straits Times Forum reply in 2012, the director of what was known as the Environmental Health Department at NEA, Mr Tai Ji Choong, said only pesticides that had undergone the World Health Organisation Pesticide Evaluation Scheme were considered for use here.
"The scheme has a rigorous four-phase evaluation and testing programme which reviews the safety, efficacy and operational acceptability of pesticides," he said.
He added that people who were "particularly sensitive to fogging should stay indoors and close the windows or avoid proximity until the fogging is over".
Jalelah Abu Baker