"We need to protect the overwhelming majority of the community who are non-smokers from the harmful effects of second-hand smoke in public outdoor areas," said Paul Klarenaar, Health Promotion Director - Northern Sydney Local Health District.
"I am excited that we can have a positive impact on so many of our community members on the day through this event."
The Forum Management Committee worked with Sydney Trains and Northern Sydney Local Health District to create a smoke-free plaza on the day to mark the international event.
Passers-by were invited to take part in a poll on their thoughts of the Forum Plaza going smoke-free for the day, with 92 per cent in favour.
Under the NSW Smoke-free Environment Act 2000, smoking has been banned at public transport stops since 2013 and around outdoor dining venues since 2015.
"Identifying the current smoke-free areas in The Forum Plaza is complex due to its unique layout," explained Paul.
"The total smoking ban removed any ambiguity and assisted smokers to comply with the legislation, if only temporarily."
World No Tobacco Day is a World Health Organisation initiative that is observed globally each year on May 31 to encourage a 24-hour period of abstinence from all forms of tobacco consumption.
Signs informed visitors that smoking was not permitted in the space. Health staff were available to measure visitors' carbon monoxide levels in their breath - a valuable tool to motivate smoking cessation as it detects active and passive smoking.
According to Paul, health is not the only benefit of smoke-free spaces like these.
"Smoke-free policies can also improve amenity and provide positive economic benefits to local businesses," said Paul.
"Therefore, we are keen to find out the community's experience of The Forum Plaza as a smoke-free space."
For more information on the laws relating to smoking in outdoor public places, or to report a breach visit www.health.nsw.gov.au/smokefree
Contact the Quitline on 137848, or visit www.icanquit.com.au if you need help to quit smoking.