Technology chiefs have insisted that their companies do not automatically retain audio data from voice assistant services.
Representatives from Google and Apple were grilled by the Dáil's Joint Committee on Communications following the raising of public concerns over the treatment of audio data.
In August, it emerged that hundreds of contracted workers for Apple in Cork were on a controversial listening operation, grading recordings from the voice assistant Siri.
The workers were stood down when Apple halted the project amid claims that people's privacy had been violated.
Gary Davis, director of privacy for Apple in Europe, told the committee that the company believes privacy is a "fundamental human right".
He said Siri uses "as little data as possible to deliver an accurate result", however he added that there is a "need for human review of a very small sample of audio interactions" to improve the service.
Mr Davis said different requests required different levels of data to be collected, for example, for a question about a football match Siri will use general location information, whereas for request for the closest supermarket, more specific information location will be used.
"This August, customer concerns arose in regard to human review of Siri audio samples. In response, we immediately suspended human review of Siri audio requests, reviewed our practices and policies and released improvements to Siri's privacy protections," he said.
These include no longer retaining audio recordings of Siri interactions by default and a facility to delete Siri history.
Google's public policy manager Ryan Meade said that the company does not and did not retain audio recordings from Google Assistant by default.
"We do not store users' data unless they choose to opt in. Opting in helps the Assistant better recognise a users' voice over time, and also helps improve the Assistant for everyone by allowing us to use audio to understand more languages and accents," he said.
"We are automatically deleting more audio data. One of the principles we strive toward is minimising the amount of data we store, and we're applying this to the Google Assistant as well. We're also updating our policy to vastly reduce the amount of audio data we store."