In the aftermath of the White Island volcano tragedy, it emerged that Australia's three skin banks were at risk of running out of human skin.

And people, understandably, wanted to help.

Melbourne's Alfred Hospital revealed people had been asking about donating skin and, while they thanked them for their generosity and support, they made it clear that:

"At this stage we are not facilitating live skin donations."

So, how can you donate skin?

Unless you're having a skin graft done in hospital, where you're essentially donating skin from one part of your body to another, skin donations can only be taken from those who have died.

Donor Tissue Bank Victoria head Stefan Poniatowski says people can't donate skin while they're alive.

"It's wonderful that people want to help but unfortunately that's not the case," he says.

"It's almost heartbreaking to be able to say that unfortunately you can't help at this moment in time."

Ash and scalding steam were released when the volcano erupted. ( AP: Auckland Rescue Helicopter Trust )

Dr Poniatowski says the best thing you can do is tell your family you want to be a tissue donor.

"We're looking for skin donations as people have died and the way that that's more likely to happen is if families talk about their decision," he says.

"Make sure that your family know what your intentions are.

"It makes that decision far easier for families."

How is it collected?

Your body won't be stripped of all its skin.

In fact, it will barely be noticeable.

Dr Poniatowski says a skin donation is like a thin piece of tissue paper and is usually taken from a person's back or the back of their legs.

"It's not disfiguring," he says.

"What's left is essentially a light graze so it looks like slightly whiter skin.

"We only retrieve from sites which are not viewable should the family wish to have an open casket funeral."

How long does skin last in storage?

Plastic surgeon Heather Cleland heads up the Victorian Adult Burns Service at the Alfred Hospital.

She says skin donations are retrieved in much the same way as skin grafts are taken from surgical patients, but then put in storage.

"It's processed and frozen and really has a shelf life of about five years or so," she told ABC Radio Melbourne.

But the fact is, there's currently not enough skin to develop a large stockpile.

A blessing service was held as attempts to bring back victims' bodies continue. ( ABC News: Brendan Esposito )

Occasionally, all the donations a skin bank has in storage can be used up just with regular burns cases.

"Sometimes the bank has trouble sourcing enough skin to provide us with normal average demand," she says.

"When there are multiple casualties we are at severe danger of running out of skin."

After the Black Saturday bushfires and the Bali bombings, when Australia only had one skin bank in operation, the country did in fact run out of skin.

"In those circumstances we try to source skin from overseas jurisdictions but there's always a delay in that arriving, which can be critical," Dr Cleland says.

"And it's not always available to be sent so when the bushfires are raging in California, for example, US skin banks may or may not be able to respond to requests from overseas."

How much skin do we have?

Dr Poniatowski says stock levels vary, but running out is always a possibility.

"It can vary from having quite comfortable stock to having literally nothing at all," he says.

"Even typical things that happen in terms of patients coming in from car burnings or house fires or typical bushfires or even explosions of barbecues or paint tins can actually wipe us out."

Dr Cleland says a very severe burns victim would need about one square metre of skin, meaning just one patient would use skin from many donors.

"It's a long haul for a patient with a major burn," she says.

"Acute treatment extends over weeks or months and then rehabilitation and recovery is years sometimes."

What about artificial skin?

It is possible for patients to benefit from artificial skin grown from a culture in a laboratory.

Australian company PolyNovo confirmed it provided extra stocks of lab-grown skin to hospitals receiving patients in both Australia and New Zealand.

Another option is 'spray-on skin', which was developed by former Australian of the Year Professor Fiona Wood and uses aerosol spray to deliver cell clusters to the affected area.

How can you help?

The experts agree: if you want to help burns victims right now the best thing to do is tell your family you want to be a skin donor.

Dr Poniatowski says that conversation would absolutely save lives in the future.

"Discuss it with your family because what we need is that tissue on standby and available at short notice," he says.

"It's not just these mass casualty incidents where skin is required and it's lifesaving.

"There are many incidents where patients' lives depend on skin being available."