The number of Emergency Medical Service (EMS) calls has been rising in recent years, and is set to rise further due to Singapore's ageing population.

In addition, the country's declining birth rates mean possibly tighter manpower resources for the Singapore Civil Defence Force (SCDF).

Both factors, among others, have led the agency to implement a new tiered-response framework from April 1, which differentiates 995 calls based on the severity of patients' medical conditions.

Previously, EMS responses were based on a single-tier system and answered on a first-come, first-served basis within a standard 11 minutes.

Under the new framework, callers who do not require emergency response will be advised to seek outpatient treatment at nearby clinics.

While the changes will free up resources for the lifesaving force to give critical cases top priority, the SCDF will also have to seek public understanding and cooperation for the new framework to work.

As Home Affairs Minister K. Shanmugam said when he announced the new framework last Wednesday: "In life-threatening emergencies, every second counts. A faster response time could mean the difference between life and death."

The call-sorting done by SCDF operators and staff nurses through quick questions must be carried out properly and its tiers made clear to the public.

It is no easy task. Last year, the SCDF handled close to 180,000 EMS calls - about 500 a day - up from some 131,000 calls in 2011. Of the calls last year, almost 19,000, or about 10 per cent, were false alarms and for non-urgent ailments such as constipation. The share of non-emergency calls rose from 5.3 per cent in 2015 and 4.6 per cent in 2014.

But the SCDF must take into account that some incidents, while minor to begin with, could easily escalate into a critical emergency. A lag between the first and second wave of responses could make all the difference.

The public must also practise discernment and not dial 995 for non-emergency cases as it means precious resources are being diverted.