The Melbourne Shield, which launched earlier this year, uses BlackBerry's AtHoc system to provide communication with participating organisations' people in times of crisis such as natural disasters or terrorist attacks.
Shopping centre operator Vicinity Centres, Deakin University and RMIT are now part of the programme.
BlackBerry chief security officer Alex Manea told iTWire that The Melbourne Shield "is fairly unique right now".
"There's going to be a very strong network effect," he predicted, meaning that the more organisations join, the more attractive the arrangement becomes.
BlackBerry naturally uses AtHoc internally, so Manea is alerted of any events that may affect him or members of his team. For example, when typhoon-like conditions hit Mumbai in August, he was kept up to date about the safety of his people who were working there.
Crisis Shield managing director Allan Briggs said "We are only just getting started, so we are thrilled to see some of the city's most well-known institutions such as RMIT, Deakin University and Vicinity Centres be among the first to join The Melbourne Shield, which is a great example of public safety best practice for other cities to learn from."
"As we welcome more members in the future, it will equip a larger group of trusted individuals with good intelligence to enable better decisions during emergencies in the CBD. Ultimately, it can be used as a tool to help protect the entire Melbourne city area."
RMIT University facilities and asset management director Brad Costello said "As we face ongoing emergency challenges, ranging from fires, floods, cyber attacks to terrorism, having access to early credible information is invaluable. In the education industry, the safety of people, whether it be students, staff or visitors to our campus is paramount and providing the most secure environment possible is a priority.
Vicinity Centres operates the Emporium Melbourne centre in the CBD. Risk manager for crisis and emergency management Marc Klomp said "Emergency services can't be everywhere at once during a major incident and The Melbourne Shield is truly a way to ensure organisations and their people are secure in any situation that may occur.
"An example of this was a major incident in Melbourne Australia early this year on Bourke Street, during which there was a long a period of time where we could not obtain credible information to make the most informed decisions. For a company like ours that sits in the heart of the CBD, the safety of people has never been more important. This is why we didn't think twice about becoming part of the network."
Deakin University manager of security and transport Rick Lloyd said "Melbourne Shield is a terrific initiative which provides a secure network for businesses in Melbourne's CBD to connect, particularly in a critical incident, and share credible and trusted information in real-time. For Deakin, the ability to send and receive emergency alerts and make quick decisions is critical.
"Every moment counts. We want to account for our people and be equipped to send them early messaging to ensure their safety."
In related news, BlackBerry has announced a new crisis communications specialisation for its AtHoc solution parters, and Crisis Shield is on track to be the first partner to receive this accreditation.
"Crisis Shield is working with BlackBerry, combining our expertise in crisis communications with the BlackBerry AtHoc platform, including our Melbourne Shield people safety initiative," said Briggs.
"With our unique skill set, Crisis Shield will now be pursuing the accreditation to become BlackBerry's first crisis communication specialist partner."