The Australian Communications and Media Authority (ACMA) has registered an industry code that clarifies how life-threatening and unwelcome calls are handled by carriage service providers.

ACMA chairman Lyn Maddock said carriage service providers have greater power to take action when such calls are made, including SMS and e-mail communications.

"If a consumer receives a series of nuisance calls or a life-threatening call, there is a clear sequence of steps to be taken by the carriage service provider to assist in the resolution of the issue," Maddock said.

The code now allows carriage service providers to suspend the telecommunications services of consumers who persist in making unwelcome calls, text messages or e-mails.

"If warnings to the offending party are ignored, switching off services after a final warning was issued is a significant improvement," she said.