OTTAWA -- Officials behind the country's system to alert mobile devices about impending natural disasters say there are still several kinks in the system to iron out, even as the alerts are being credited with saving lives just last week.

Mobile alerts went out across the National Capital Region on Friday as a storm slammed into the region and unleashed what Environment Canada now says were six tornadoes -- three each in Ottawa and Gatineau, Que.

About 100 alerts have been issued across the country since April 6, when wireless warnings were added to the traditional television and radio messages broadcast by the National Public Alerting System, said Scott Shortliffe of the Canadian Radio-Television and Telecommunications Commission.

Yet while many of those alerts have been successful, Shortliffe said in an interview that issues remain, including that only cellphones and wireless devices connected to an LTE network can receive the messages.

The system uses what is called "cell-broadcast technology," which sends a message to all wireless devices within a certain geographic area with local cell towers, rather than sending messages to individual phones.

"The problem that we face is because the system is so complicated and there's technological change, there are new handsets that enter the market constantly, we see that new problems can crop up," he said.

"Even on a system that's been working perfectly."

It's believed such a problem was behind a three-hour delay in the issuing of an Amber Alert in Saskatchewan last week, while Shortliffe said he has heard from some residents in the National Capital Region who never received a tornado alert on Friday.

"I was thrilled that there were people who gave the system public credit that it saved lives in Dunrobin when the tornado came through," he said. "But I'm also aware that there are people who are saying: 'My phone didn't go off. Why didn't my phone go off?"'

Another issue identified for the Gatineau tornadoes was that some of the messages broadcast in Quebec were in English only, though Shortliffe said responsibility for the language and content of warnings lies with the provincial or municipal government issuing the alert.

While testing is set to continue across the country and the CRTC has directed all cellphones sold in Canada be capable of receiving the alerts by next April, Shortliffe expected there would continue to be some problems, particularly as people hold onto older phones.

In the meantime, officials plan to continue conducting tests to ensure any problems that crop up are identified and addressed as quickly as possible -- and before a life-threatening emergency hits, not when it is already bearing down on people.

"The good thing is we're all concentrating on the same outcome, which is find out where the problem is and fix it to make sure it's not repeated next time," Shortliffe said.

Government officials have identified 19 different life-threatening events that can trigger a warning, including fires, terrorist attacks, floods and tornadoes, air-quality concerns and animal dangers.

There are 988 bodies across Canada that can issue an alert, including federal departments and agencies as well as provincial and municipal authorities, such as police and emergency-response centres.

Those bodies are responsible for drafting specific alerts and sending them to Pelmerex, a company licensed by the CRTC to relay warnings to broadcasters and wireless providers, who are then responsible for sending them over the airwaves.

Pelmorex owns The Weather Network.

A first round of nationwide tests was conducted in May to mixed results that included technical problems with certain wireless networks in Ontario and a coding error that prevented any messages from being sent in Quebec.

While most of those problems have since been fixed, Shortliffe said one major concern is the entire system hasn't been tested in Quebec. A new round of national tests hasn't been scheduled.

In the meantime, Shortliffe said people can check to see whether their phones are compatible with the alert system by going to AlertReady.ca. Anyone who didn't receive a warning even though their phone is compatible should contact their wireless provider.