Controversial spit masks similar to those used on juvenile inmates in the Northern Territory have been deployed on asylum seekers in Australian immigration detention, and authorities reserve the right to use the equipment on children.

The revelation shows that contentious restraint methods are being used against vulnerable people in all types of Australian detention facilities, and are not limited to the NT youth justice system. Human Rights Commission president Gillian Triggs has called for a national monitoring system for all forms of detention, including scrutiny of restraint methods.

Harrowing Four Corners footage showing Abu Ghraib-style "spit hoods" being deployed against children in the Don Dale youth centre was widely condemned, forcing the NT and West Australian governments to suspend or abolish their use against detainees in juvenile justice.

In WA, spit hoods have reportedly been replaced with surgical masks and eye shields for staff, following a trial of that protection method.