"We've encrypted our radios, as most police services, by the way, in North America have, just to maintain the security and the integrity of our operations," he said Tuesday, when speaking with reporters.
Blair said the change means that members of the public and the media won't be able to be "eavesdropping" on police communications any longer.
The police chief said the service will take steps to keep the public informed about its activities through other means, including through social media.
Blair is in the final weeks of his job as police chief, after spending a decade serving as the city's top cop.
While he is considering his options for his future, Blair said that for now, he remains focused on his job at police headquarters.
"While I'm doing this job, this is what I'm doing," he said.
Blair had sought a third term as chief, but the police board told him last summer that it would not be renewing his contract.
On Tuesday, he admitted to being "a little envious" of the next person to take on the job as the city's top cop.
Blair said he's also willing to provide advice to his successor, should he be asked to do so.
"If they ever need my advice, I'll be there to help," said Blair.