Telemetry is now a frequently heard word in everyday life. It may be telemetry from a Formula One car whilst you’re watching the Grand Prix, telemetry being talked about when a rocket launches and sends information back to NASA ground control or even when a probe is launched from the Enterprise during Star Trek. Telemetry technology is also being increasingly used within the fire and rescue service.
Telemetry is usually defined as the automated transmission of data from one point to another. The data is collected from remote or inaccessible locations and sent by wire, radio or other means to a receiving station for monitoring, display and recording. Telemetry has been used for a variety of applications. Some of these include monitoring chemical plants, transmitting meteorological data, gathering flight testing data and for cardiac monitoring in healthcare. The first examples of telemetry appeared in the late 19th century when data was sent through physical wires, and then later by transmitting data wirelessly over radio waves.
Differences between electronics and telemetry
Breathing apparatus (BA) sets are more commonly being fitted with electronic gauges and you will often hear this described as a set with telemetry. In reality this would not actually be a telemetry system. A true telemetry system would actually need to be fitted with a method, most typically a radio module, of transmitting data to a remote point. Therefore not all electronics systems are ‘telemetry’ but generally all telemetry systems are electronic. For example, if the pressure cylinder gauge is just telling the user what the pressure is, then it is an electronic system rather than a telemetry system. True telemetry sends information back, like air pressure, man down alarm and evacuation acknowledgement. Telemetry can also be closely linked to accountability, where systems keep track of personnel and their locations and can play a vital role in keeping firefighters safe. Basic accountability systems however do not necessarily use telemetry.
An impact on firefighter safety
During fire and rescue operations telemetry is often used to transmit data to and from individual BA sets to an incident commander or entry control officer to allow for the remote monitoring of these BA sets. The three most common elements of telemetry data that are presently used for the firefighters are man down alarms, air pressure information/monitoring and evacuation signals. These streams of information are used in different ways by the recipient.
1 Man down alarms
Traditionally fire brigades use man down alarms. These are worn by the firefighter and after a period of no movement, activate a loud audible alarm. These alarms are then heard by personnel outside the incident allowing them to know that they have a firefighter in trouble. There is a possibility during the fast paced nature of an incident that these alarms may not necessarily be heard immediately and therefore potential rescue delayed. With telemetry enabled man down alarms then the principle is that, as well as an audible alarm, the man down unit transmits a signal that activates an audible or visual alarm on the entry control officers’ (ECO) information system ensuring that the signal is not missed. The benefit with this type of information is the immediacy of the notification which enables a more rapid response to the situation.
2 Air Pressure
Traditionally the entry control officer will base the amount of time that a firefighter should be in a job for on an average estimation of air consumption and therefore a standard calculation of the expected duration of each of the BA sets. With consumption rates dependent on work rates and the type of activity being undertaken, individuals often exceed or are below the consumption rates set within manual calculation tables making it more difficult to manage BA resources safely and effectively.
With modern telemetry systems the air pressure is transmitted back to the entry control point allowing the ECO to know in real time exactly what contents each of the firefighters they are responsible for have in their cylinders. This takes away the estimation element and allows the ECO to have a better awareness of the situation for every person in their team. For example if the firefighter has been able to conserve air and therefore has stayed in the job longer than the original estimated time then the ECO can see that they have air remaining and would not need to deploy anybody extra into the incident to see if there was a problem.
More sophisticated systems will also take this air pressure information and the users breathing rate (based on measurements taken over the previous minutes) and automatically calculate for the ECO a time of whistle. This time of whistle can be dynamic which means it changes based on the individual’s consumption rate of air which will depend on how hard the firefighter is having to work. If the firefighter is still in the incident when their end of service life alarm goes off then that alarm is sent to the ECO as well.
3 Evacuation signals
The third element is that telemetry provides the incident commander or entry control officer the ability to evacuate their wearers at the push of a button. Traditionally evacuation is done by different methods depending upon where in the world you are, for example in some areas three blasts on a whistle, a loud horn, or communication via the radio and voice messages.
Telemetry systems allow the ECO to instantly communicate with the BA wearers both selectively or en-masse and signal to them that they must evacuate. Sophisticated systems also enable the BA users to acknowledge that signal which notifies the ECO that they have received and are responding to their alert.
Inbuilt into many systems is also the ability to store and analyse this transmitted data, for example the systems will log data such when a fire-fighter is accepted onto the system as they enter the incident and become the responsibility of the ECO, when they go into alarm and when the ECO has responded to that signal. This data can then be used for later analysis and incorporation into reports. Some systems will even output that data into a standardised report form that will enable the officers to compile and submit their incident records in a much more time efficient manner.
Telemetry across the World
Currently telemetry systems vary between countries, both in terms of their prominence, their appreciation, their form and how they are used. For example, the US uses telemetry systems in which the displays for the control officer are mainly computer-based, whereas in the UK a tally board system is primarily used.
In general users in the US have a positive attitude towards telemetry and appreciate the benefits it can offer. As with any new technology, adoption starts off slowly and gathers pace as the benefits of the systems become more recognised and valued. Similarly within Europe, the usage of telemetry varies greatly, with some countries being more progressive than others. In terms of ECO displays some European countries use computers; others prefer a simpler device similar to a pager or methods such as an electronic tally board. The UK brigades are arguably the leaders in telemetry usage as the take up is much more advanced (approximately 40% use telemetry systems) so as a result proportionately there are more telemetry systems in the UK than anywhere else in Europe. This is possibly because of the formalised entry control procedures employed by the UK fire services which enable the benefits of telemetry to be easily incorporated and realised within its structure.
Recognising the different attitudes towards telemetry, manufacturers are driving telemetry development to suit different markets and to meet user demand and capabilities, including simple pagers, tally boards and computer based systems.
The future of telemetry: location technology
With 40% of the UK fire and rescue services using telemetry systems and less across Europe and the States, there is plenty of room for growth in this market. As technology becomes more sophisticated, fire services are realising the true potential of telemetry systems. As a result, one of the key areas for development is the use of intelligent location technology combining telemetry and accountability. For example, building plans (such as hospitals, stadiums and factories) are becoming increasingly available which, when loaded onto mobile data terminals, could in the future allow the control officer to track a firefighter’s location remotely, accurately and in real time. With so many benefits customers across the world are asking for it despite the technology being in its infancy. The process to ensure that the technology is reliable and robust enough for service use would be a complex one, however it is a process many research groups are activity looking into.
Another area for growth is the ability for firefighters to track each other during fire operations. In the States every Scott Safety Air-Pak is fitted with a Pak-Tracker radio module which is triggered manually or by the activation of the man-down alarm and acts as a beacon allowing a rescue team to locate them in much quicker time.
The future of telemetry: data development
It is also expected that more firefighting equipment will eventually become wireless compatible, so as well as telemetry enabled BA sets, items such as gas detectors and thermal imaging cameras will be able to communicate with each other and provide the ECO with further information. With thermal imaging cameras this means that the information is being sent to the control point outside the building, enabling the control officer to see what the firefighter is seeing. The gas detectors would also be able to provide and send information so that control officers could better monitor the atmosphere and see any changes that were happening as well as the individual firefighter.
The future in action
Discussions are often had where end users question whether voice radios can be used to send SCBA information. Recently Scott Safety and Motorola Solutions announced a product development agreement to enhance firefighter safety and accountability in the States. Central to this agreement is the capability to transmit critical Scott Air-Pak Self Contained Breathing Apparatus data, such as air levels and PASS (man down) alarm data, over Motorola APX™ Project 25 portable radios. The agreement is a fundamental step towards providing better integration of fire ground equipment within the communications and accountability sector.
When you look back at the origins of telemetry in the fire service, it is quite astonishing the progress made since the original telemetry enabled ‘man down alarms’ were first released. Over the coming years that progress will continue and equipment will be developed that further improves the safety of first responders and will provide capabilities that would currently be thought of as something that you may only see in a Science fiction film.
For more information, go to www.scottsafety.com