Historic legislation allowing terminally ill people to end their own lives has passed the West Australian Parliament, making it the second state after Victoria to allow voluntary euthanasia.

Key points: The procedure will only be for those with a terminal illness and need medical sign-off

The procedure will only be for those with a terminal illness and need medical sign-off The laws passed after months of heated and passionate debate on both sides

The laws passed after months of heated and passionate debate on both sides While there are a series of safeguards, critics maintain they are "dangerous"

Supporters of the bill cheered and gave a standing ovation from the public gallery as the Legislative Assembly voted it into law.

There were also emotional scenes on the floor of Parliament as MPs hugged each other in celebration after months of drawn-out debate.

Health Minister Roger Cook held back tears as he delivered his final address to the house.

Premier Mark McGowan thanked supporters outside parliament. December 10, 2019 ( ABC News: James Carmody )

WA Premier Mark McGowan said it was a historic, but also sombre, day for all those who fought for years to give terminally ill people the option to legally end their pain and suffering.

"This is Western Australia leading the way for the entire country — and the whole world — in social reform that makes people's lives better," Mr McGowan said.

"This is about allowing for choice for those people who are dying and in pain, so that they don't have to go through those last weeks and months in agony.

"It means all those people who are worried about their own futures, worried about their parents' futures, will have the comfort of knowing that if they're dying and in agony, they can exercise their own choice.

"It is a fundamental question of human rights to be able to exercise your own choice in that situation."

VAD supporter Rhonda Taylor said she was overwhelmed by the result. ( ABC News: James Carmody )

Lower House MPs had returned to Parliament for a special sitting to debate 55 amendments to the legislation made by the Legislative Council, which had debated the bill for more than 105 hours until it was passed last week. All the amendments were passed, with the Government's support.

A series of safeguards

The Government argued the amendments did not impact the operation or the integrity of the bill, which had more than 100 safeguards in place.

Under the scheme, to be eligible a person would have to be terminally ill with a condition that is causing intolerable suffering and is likely to cause death within six months, or 12 months for a neurodegenerative condition.

A person would have to make two verbal requests and one written request. Those requests would have to be signed off by two doctors who are independent of each other.

The choice of lethal medication would be a clinical decision from an approved list of drugs.

Self-administration would be the preferred method, but in a departure from the Victorian regime, a patient could choose for a medical practitioner to administer the drug.

In Victoria, a doctor can only administer the drug if a patient is physically incapable.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 41 seconds 1 m 41 s How pharmacists will dispense drugs to eligible Victorians under the state's assisted dying laws

'Dangerous' laws still have critics

But Upper House Liberal MP Nick Goiran, the most vocal opponent of the bill and who spoke on every clause in the Legislative Council, maintained it was the most dangerous voluntary euthanasia legislation ever passed in Australia, even though he had proposed 25 of the 55 amendments passed.

He previously said unlike the Victorian legislation, there was no requirement for a specialist doctor to be involved and patients could self-administer the lethal medication with no supervision.

Labor MP Amber-Jade Sanderson, Health Minister Roger Cook and Premier Mark McGowan celebrate with voluntary euthanasia supporters. ( ABC News: James Carmody )

They also did not have to keep the medication in a locked box.

Mr McGowan stressed it was a voluntary scheme.

"Those people who want to access it, will be able to access it," he said.

"Those people who don't want to access it, won't have to access it. It's a voluntary decision on one of the most important periods in your own life, which is when you are dying and when you are in pain."

An 18-month wait to access the program

There would now be an 18-month implementation period to give health and other service providers time to prepare for voluntary euthanasia before it comes into effect.

The voluntary euthanasia debate brought out passionate arguments on both sides. ( ABC News )

Health Minister Roger Cook said WA would benefit from Victoria's experience in bringing voluntary euthanasia into law.

"We'll obviously borrow a lot from Victoria, Mr Cook said.

"But Western Australia is a unique landscape, over 2.5 million square kilometres of country we have to make sure we spread these laws to.

"So we're going to take very cautious steps to ensure that when we implement these laws that it's absolutely safe and that everyone has the opportunity to access voluntary assisted dying."

A little too late for some

Rhonda Taylor, 54, has campaigned for VAD but it will not be available soon enough for her to use it.

"I have metastatic breast cancer which has spread to my brain and right throughout my bones," she said.

"I'm facing the prospect of losing my speech very shortly, have difficulty swallowing and eating, so I'll be looking at having a tube for eating, my hearing has gone, some of my vision is going, I will be looking at having some sort of paralysis.

"I'm degenerating very quickly, so I'm hoping to see out Christmas and a little bit beyond for my daughter's birthday, but I'm not so sure."

VAD supporter Rhonda Taylor leaves parliament after listening in to hours of debate. ( ABC News: James Carmody )

Ms Taylor said she was overwhelmed when the bill passed this evening and said thousands of people could be helped by it.

"There are thousands of people like me, in my situation. I just think that's such a gift to give to somebody," she said.

"Knowing what's coming and knowing that you can prepare for it in a way that's not going to traumatise yourself or people around you that you love.

"And you can make that time a special time rather than them remembering you as somebody that was maybe struggling to breathe, in pain and they can't do anything about it."