Patients are being put at risk by a failing radio network used by ambulance crews across New South Wales, the Australian Paramedics Association (APA) has warned.

The APA said the system was being undermined by signal blackspots which it said were rife across the state, and equipment was not being maintained

Ambulance officers carry portable radios on their shoulder and use car radios to communicate with each other and alert hospitals during an emergency.

President Steve Pearce said the system was malfunctioning and paramedics were resorting to desperate measures.

"Leaving their partner whilst they are working on patients so they can go back to their car radios and in some cases go to the general public to use their satellite phones," he said.

"It's certainly been the case that patients haven't got the care that they deserve and lives are put at risk because of the lack of radio infrastructure.

"If a paramedic is trying to save someone's life and actively working on someone and going to use the portable radio on their shoulder and finding they can't get through to the control centre to get help for the patient, it is extremely stressful."

The APA said radios failed during two patient callouts in Albury this month, where both patients later died.

Mr Pearce said the radio bandwidth and infrastructure must be upgraded to the standard used by other emergency services such as police and firefighters.

However, Michael Homden from New South Wales Ambulance said there had been significant investment to iron out flaws.

"There's been over $36 million in capital funds invested over two years in advancing the system, increasing technology and enhancing communication," he said.

"We work closely with other emergency services, telcos, the union and paramedics on the current and future state of the system, making sure where we identify blackspots and/or a lack of connectivity, we audit those blackspots and indeed audit the system."

NSW Ambulance takes patient safety 'very seriously'

NSW Ambulance would not comment on the recent deaths linked to radio faults by the APA.

"We take the safety of all patients and paramedics very seriously and we continue to make sure where problems are identified we respond," Mr Homden said.

NSW Opposition health spokesman Walt Secord said the State Government must honour its commitment and upgrade the radio network.

"In the 2015 election, they said they were going to create a world-class paramedic service and now we find a situation where patients wait longer and paramedics are put into unfair situations," he said.

He said lengthy waiting times for ambulances in NSW must also be addressed.

"NSW has the second longest wait for ambulances in Australia after Tasmania, 11 minutes compared to 9.4 minutes [as a] national average. This is unfair to patients and paramedics because in an emergency every second counts," he said.

Ambulance tracking software was criticised last year for being out of date and unreliable, causing a blowout in response times.