"It is becoming routine to […] have half a dozen or more patients sitting in the emergency department waiting for a ward bed for more than 48 hours and, in occasional cases, 72 hours," the source said. "Every day of every week for the last year, at least a year, it's been routine.

"This is the norm. There is a chronic shortage of ward beds."

Fairfax revealed patients at Blacktown had been waiting up to 40 hours to be admitted to a hospital ward last week. The Health Minister, Jillian Skinner, blamed an "unusual spike in patient demand".

But more major delays played out on Monday.

Fifty-seven patients were in an emergency department with capacity for 42, the nurses and midwives' union said.

Paramedics waited with one patient for 17 hours to hand them over to the hospital on Monday. By 5pm, another patient with heart problems and difficulty speaking had been waiting with paramedics for more than seven hours.

Leaked figures also show the hospital's backlog last week was far worse than previously reported.

A dozen patients were left waiting for more than 48 hours on Monday afternoon. Half were aged 80 or over.

A further five patients had been waiting 24 hours, while another was left in a resuscitation bed for 14 hours.

"It's being demonstrated on an almost daily basis that the hospital cannot cope," said acting general secretary Judith Kiedja. "Our members are sick and tired of abuse [from patients facing major delays]."

But Mrs Skinner said there were "clinical reasons why a small number of patients may spend an extended period of time receiving care in emergency departments".

A 2012 federal government report found 10 per cent of patients at Blacktown waited longer than 27 hours for admission. It was ranked the nation's second worst hospital on this measure.

The NSW health source said routine overcrowding in the emergency room at neighbouring Mount Druitt is worse.

Recently a patient with an infection faced an overnight wait just to move from the waiting room into the emergency department itself.

"She was admitted and then put back in the waiting room. She would have to sit in the waiting room [overnight] before getting a bed in the emergency department."

Less seriously ill patients at Blacktown are usually seen by doctors within 30 minutes of arriving in the waiting room. Doctors can quickly order tests and start treatment before patients return to the queue.

But hospital workers say it's hard to attend to patients in emergency departments when new ones are walking in the door and the environment lacks privacy.

"We've often got six admitted patients sitting in recliners waiting to go to the ward. These are counted as beds. We've had patients go straight from one of those into resuscitation and intensive care. It makes the staff nervous.

"If they deteriorate it can go unnoticed until it is too late."

Delays are also increasingly taking ambulances off the road.

"Our members say [eight hour] delays have become the new norm in the past fortnight," said Steven Pearce, a spokesman for the Australian Paramedics' Association. "We need to get paramedics back on the road."

Danny O'Connor, chief executive of the Western Sydney Local Health District, said more ambulances had been arriving at the hospital. "We have also experienced an increase in activity treating patients with respiratory and geriatric conditions," he said.

The federal government benchmark for having patients leave an emergency department is four hours.

On Monday the Health Minister said she remained "absolutely committed" to that target, despite refusing to sign up to a new federal government standard for processing 90 per cent of patients in that time.