Emergency Communication for Mass Transit Application

Impact Technical Products along with Guardian Telecom (a Canadian telephony company based in Calgary) were tasked with providing an emergency telephone solution that would be robust enough to survive a 25 years design cycle and provide reliable communications in harsh environmental conditions. They had reviewed the market and did not find a product for the job.

 

THE CHALLENGE

 

The challenge began with the transit company outlining a list of features and functions required for their new underground telephone system. They reviewed the existing emergency telephones available from Guardian Telecom. Although many had the elements required, there wasn’t one model that met all the unique requirements of their mass transit underground. They stated the reality that these telephones would not be used very often, but if an emergency occurred in the subway tunnels they had to work reliably.
 

They asked us if we would design a unique telephone to meet their needs that would combine the harsh rated features of the Guardian Telecom products.

The product had to have:

• solid state circuitry — sealed to the elements

• a positive action hook switch that would always close off the communications (lines cannot afford to be left open underground.

• vibration resistance to the rumble and roll from fast moving subway trains

• corrosion resistance to the elements

• the ability to change components and repairs very quick as there is very limited 'tunnel time' available during the night

• rugged construction to withstand harsh conditions

• availability for in-tunnel use as well as outside on the surface exposed to the elements, and use common components.

THE PROCESS

They asked for ideas and designs from several manufacturers over a period of 18 months. Prototypes were submitted along with factory test results at their request. Several designs and prototypes were taken to an independent testing laboratory and finally, after engineering reviews, selected the custom telephone designed by Guardian Telecom.

THE RESULTS
 

Since that decision was made over 5 years ago more than 1000 telephones have been deployed underground and above ground. The product has met the challenge, continues to perform and exceeds expectations.

The next challenge may include VOiP telephone as well. If it does, Guardian Telecom is ready to meet the challenge.