In Australia baggage handlers, caterers, engineers and maintenance staff will undergo random testing for explosives in a new security crackdown.

The Turnbull government announced the new measures today, just months after an alleged plot to smuggle an explosive onto an international flight from Sydney Airport was foiled.

Transport Minister Darren Chester says the new checks strengthen existing controls by ensuring airport staff are authorised and appropriately trained before entering secure areas.

They may also be checked while working.