It is understood that the Department of Health found it was not able to include the vaping devices in the workplace ban because the evidence of the harm they caused was not strong enough.
The department has said current evidence did not support prohibiting e-cigarettes in public places but individual organisations and businesses were free to introduce an e-cigarette-free policy.
The ICS had been hoping that e-cigarettes would be included in the workplace smoking ban when legislation to transpose the EU Tobacco Products Directive was introduced next year.
“While it is clear that e-cigarettes are far less harmful than tobacco smoking, we are concerned that the success of the 11-year-old workplace smoking ban in de-normalising smoking may be undermined by not extending it to vaping,” the ICS stated.
The society is concerned that the current situation regarding e-cigarettes creates a legal limbo for individual businesses, some of which have already decided to prohibit vaping in the same way as tobacco.
Research commissioned by the ICS earlier this year showed that over half (53%) of the Irish public would support the inclusion of e-cigarettes in the smoking ban.
The ICS pointed out that Wales and Portugal were both planning to extend their smoking bans to cover vaping.
“We will be calling for the Department of Health to reconsider their position as they draft the first regulations on e-cigarettes which are due to be in place by May 2016,” it added.
The department said it would continue to monitor evidence on the potential harms and any benefits of e-cigarettes.
In the meantime, while more research was awaited on the harms and benefits, there was a need to ensure that there was some regulation of e-cigarettes.
It said the Government had approved the drafting of legislation to introduce a licensing system for e-cigarettes.
The legislation would also prohibit the sale of the products to and by persons under 18 years of age.
The department is also working on transposing the revised EU Tobacco Products Directive into national law. It provides for the regulation of certain aspects of e-cigarettes across the EU.
The directive will set safety and quality requirements and make health warnings and information leaflets obligatory.
The directive also gives the EU the power to prohibit any electronic cigarette or refill cartridges if concern is raised regarding an unforeseen risk to public health.
In August, Public Health England, an agency of Britain’s Department of Health backed the use of e-cigarettes because they were 95% safer than smoking tobacco.
It suggested that e-cigarettes could one day be offered alongside nicotine patches as a smoking cessation aid.