A Qantas worker has been stood down after spreading their concerns over the safety of boarding planes that had come from China.

The man, who worked as a health and safety advisor for Qantas, told other employees they could strike if they had concerns working on planes that had come from Beijing or Shanghai.

The employee, who was also a union delegate from the Transport Workers Union, was stood down on Sunday after his claims were dismissed by Qantas.

The airline said employees and passengers who boarded planes from China were at a 'very low' risk of contracting the virus.

A union delegate from the Transport Workers Union (TWU) told other Qantas employees that it was unsafe to board any planes that had come from Beijing or Shanghai and was let go by Qantas over the weekend

On Alan Jones' Breakfast show on 2GB on Thursday, the broadcaster read a letter from Qantas warning two cleaners they could be fired for refusing to board a plane.

'(The employees) refused to board an aircraft and perform your duties. You advised this was due to your concerns of the risk of contracting coronavirus,' Mr Jones said while reading the letter.

'You were advised at the time that the risk of that occurring was negligible. In these circumstances and with the information available to you, you can not reasonably be concerned that working on an aircraft originating from China would expose you to a serious risk to your health or safety.'

'If you fail to comply with this direction it may result in disciplinary action taken against you up to and including termination of your employment.'

The worker was telling other staff it was unsafe to board Qantas planes from Shanghai and Beijing due to the risk of contracting coronavirus

Dr Russell Brown, who works in Qantas' Medical team, said the risk of contracting the virus was very low.

'We would never ask our employees to work in unsafe conditions,' Dr Russell said in a statement.

'The TWU knows full well that the risk of aviation workers contracting coronavirus as a result of working on an aircraft originating from China is very low. I briefed them on the situation last week.

'Our medical team is in regular contact with health authorities and is receiving the latest advice from Australia's Chief Medical Officer and the World Health Organisation.

'Additional protective measures are being put in place on flights from China to further reduce the risk of our employees contracting coronavirus and we are providing them with regular updates on the latest health advice.'

But TWU National Secretary Michael Kaine defended the union delegate who was let go, saying their concerns were reasonable.

Passengers in Auckland airport wearing face masks amid the new arrivals from the epicentre of coronavirus

'We rightly lauded the actions of Qantas in sending in a rescue mission and we support the brave volunteers on that flight but there's a double standard here isn't there,' Mr Kaine said on 2GB Radio.

'These workers know that these planes have come in from the epicentre of the virus, they have to go home to their families at night thinking that they may be potentially infected.

'It's a reasonable concern, people are dying left right and centre. How is it unreasonable to be concerned about your health and safety? You can imagine there's a level of anxiety that goes with it.'

On Monday a Qantas flight from the Chinese province of Wuhan landed in Western Australia carrying hundreds of Australian evacuees.

Evacuees have since been flown to Christmas Island where they are to be quarantined for two weeks.