It's huge, it's delicate and it's historically and artistically significant, so cleaning and conserving the Great Hall Tapestry is no mean feat.
Part of the process of cleaning one of the most awe-inspiring artworks at Parliament House includes deep-freezing the material to kill any insects or eggs that may have infested it. Just another version on Capital Hill of putting your enemies in the deep-freeze.
The tapestry, measuring 20-metres wide and nine-metres high, has hung in the Great Hall of Parliament House since the building was opened in 1988.
This week, for only the fourth time in the last 38 years, the tapestry has been taken down and turned over, for conservators to clean and preserve the back of the work.
They have used a quieter time during the winter recess of parliament to methodically inspect, clean and document the tapestry, working on its four panels one at a time.
By contrast, the front of the tapesty is inspected and cleaned every two years in situ, hanging in the hall, with conservators using lifts to reach every corner.
Department of Parliamentary Services art collections director Penny Grist and conservation manager Jess Wignell said the tapestry this week was laid down on the floor of the Great Hall and the back of it was painstakingly inspected and cleaned.
"So it's a visual inspection first with magnification and light and then anything that is foreign is removed and bagged and we've annotated where they've come from just so we've got a record of what sort of things have been around," Ms Wignell said.
"Then there's the cleaning of it and we then we move on to the next panel."
The tapestry was first frozen off-site to a temperature of minus 20 degrees to kill any bugs or eggs, especially moth eggs.
Each section was inspected and documented and vacuumed, but through a gauze so that none of the material was sucked up.
"They're looking for any damage or anything could potentially be damage - but there's no damage," Ms Wignall said.
"But we're also looking for any debris, like dust, moths, insects, eggs, casings, so evidence of insects. And basically the debris that can come from being in an open space."
Ms Grist said the Great Hall was used by thousands of people each year, with the tapestry usually always hung over them.
"And it's in absolutely incredible condition for such a high-public, high-use space," she said.
Ms Wignell said: "Because the light is so low in here, the fibres are in really good condition. They haven't been subject to really high light levels which means fading, so we're pretty lucky it's in such a great space".
The tapestry is one of the biggest in the world, commissioned for the opening of Parliament House, and covering almost the entire southern wall in the reception hall.
It is based on Arthur Boyd's large landscape painting Untitled (Shoalhaven Landscape) (1984).
Fourteen weavers from the Victorian Tapestry Workshop (now the Australian Tapestry Workshop) took two years to complete the work.
The team from art collections at the Department of Parliamentary Services were thrilled to be working on it.
"It's a real honour," Ms Grist.
"Yes, a huge privilege," Ms Wignell said.
"It is the largest tapestry in the southern hemisphere and one of the most important artworks in Australia. You can't think about that too much while you're working or else you get too awe-struck by it. You've got to take it step by step."
The Great Hall Tapestry is expected to be back in place around August 5.
