Up to 450 workers at Perth's new children's hospital have signed an "asbestos register" to monitor their future health and possibly lead to compensation in the wake of the discovery of the deadly material.

Asbestos was discovered last week in a roof panel installed in the incomplete $1.2 billion hospital, leading to the area being isolated.

Construction union WA secretary Mick Buchan said affected workers felt shock and disbelief, including some who were showered in plumes of asbestos-riddled dust and had then gone home to their families in dirty work clothes.

“Everyone is sort of in shock. Still in shock that something like this can happen in 2016, particularly on a state government project, where you would think control measures would have been in place,” Mr Buchan said.

WA’s Opposition Leader Mark McGowan said the government should not open the hospital, which is due to start taking patients in three months, if there was the slightest risk to any staff or children.

The discovery has sparked fears Australia-wide, with revelations that the Chinese company Yuanda that supplied 150 roof panels to the hospital has supplied building products to 69 sites across Australia, including Perth’s new 60,000 seat stadium and Fiona Stanley Hospital.

Yuanda was also caught out supplying asbestos-tainted gaskets to a new government building in Brisbane last week.

The scandal has put the spotlight on the Australian Border Force and its border controls, which says it only checks a small sample of shipments, and given the panels were certified asbestos-free in 2013 by Chinese and Australian inspectors.

Federal Border Protection Minister Peter Dutton has not publicly released an independent review of Australia’s asbestos border control completed earlier this year, despite criticism from the Queensland and WA governments.

“The federal government does need to be rather more proactive on this issue. They need to be on the front foot in explaining what they’re doing in relation to monitoring the importation of products into Australia,” WA Health Minister John Day said.

WA opposition health spokesman Roger Cook said concerned workers should sign up to the register to safeguard their right to compensation against future medical issues that would hopefully not occur.

WA building commissioner Peter Gow is conducting an independent audit into the hospital project and its management by John Holland and Yuanda, warning breaches of the law will lead to fines.