Emergency Communications
Mobile Phones
Mobile phones can work if you are near a township or highway, however phone network coverage is not complete in remote areas of Australia. In an emergency it is generally the fastest and easiest way to summon help. Your best chance of coverage is from a high spot such as a hill or lookout, but you are unlikely to ever get coverage in a canyon or gorge. If you don't have enough coverage to make a voice call sometimes you can still send a text message (SMS) as it often works with lower signal strength than is required for a voice call.
If you are using a mobile phone to dial emergency, the first number to try is 000. This will connect you to the emergency operator using your normal phone provider. If you cannot connect to the operator with 000 for any reason (including no coverage) it is recommended you then try 112. 112 will also connect you to the same operator as 000 emergency but has a number of additional benefits:
- It is an international standard that a mobile phone dialling 112 is an emergency call. If you dial 112 with a GSM phone anywhere in the world it will connect you to the local emergency operator.
- 000 will only work with the phone service provider you are subscribed to. If any provider detects a 112 call they will connect you. This means, for instance, if you are a Vodaphone customer and are in an area which does not have Vodaphone coverage but does have Telstra coverage, Telstra will connect a 112 call for you. Telstra would not connect a 000 call made on a Vodaphone mobile phone.
- If a mobile phone network is running at capacity a 112 call will cause a non-emergency call to be dropped immediately to make capacity available. This does not necessarily occur with 000. This means if the network is running at capacity and you call 000 you may not get connected.
Note that 112 may not work with some CDMA mobile phones. Check with your mobile phone service provider if you wish to know whether 112 works with your phone.
When you get through to an operator you will be asked which service you require. If you have a medical emergency you should ask for Ambulance, if you have a situation were you require rescue you should ask for Police. The operator may ask for a street and nearest cross street. The operator is trying to find where you are so you can be connected to the local emergency service for your location. In a remote area "street and cross street" is often not appropriate so you may have to explain the situation and suggest a nearby landmark the operator would be able to identify, such as a nearby lookout, mountain top, access road or river. If the operator insists on a street and cross street ask to talk to their supervisor. When you are connected to the service you require you should start being more specific about your location using grid references or local landmarks. Try to minimise mistakes with grid references by also giving a nearby landmark.
Do not hang up until you have confirmed that it is OK to do so. Keep your phone on if possible as they may try to ring you back, but be aware of the limited battery life of phones. If you are running low on battery life you should consider using text messages (SMS) as they use much less battery power than voice calls. If you turn your phone off to save battery life make sure you arrange a time with emergency services to turn it back on again.
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Using Mobile Phones in Areas of Marginal Coverage
Be aware that a mobile phone in an area with a weak signal will use much more power trying to maintain the signal. Your phone battery may only last a few hours in the "bush" or any other region with marginal coverage - even though it may normally lasts for a week or so where you live. This is because the phone is transmitting small messages to the phone network every few minutes so the network can contact the phone if it has a call for it. The phone controls the signal strength of these messages so it does not use more battery life than is necessary - it transmits with just enough strength for the phone network to receive the message.However in marginal coverage areas these frequent messages need to be sent with a lot of power to get through. This means you should expect the batteries to be consumed in a fraction of the time they normal last in the city which has good signal strength everywhere.
So we recommend you keep your phone off until you need it. If you make a call you should turn your phone off again afterwards. However if you have called 000 or 112 do not turn your phone off unless instructed to by the operator - they may need to phone you back - but do point out that you are in a remote area and that you may have limited phone battery power available.
What Do You Do If You Don't Have Enough Signal Strength To Make A Call?
This is a common problem in bushwalking areas - your phone is picking up a weak signal from the network but it is not enough to make a call. In this case we recommend you try sending an SMS. It takes a fraction of the battery power to send (or receive) an SMS compared to a voice conversation, it works on much lower signal strengths than voice conversations and it has built in error-checking so your message should get through correctly. However there are some important limitations about using SMS in emergencies:- The 000 emergency line cannot receive SMS messages. You must send the SMS message to somebody you know with a mobile phone and they must contact 000 on your behalf.
- SMS messages are usually sent to the recipient immediately, but on rare occasions can take a period of time to get through the network before being sent to the recipient's phone.
- If your friend has their mobile turned off they will not get the message until they switch their phone on, and you have no way of knowing this.
Is 000 Really Worth Calling?
The Coronial Inquest into the death of David Iredale on a bushwalk near Katoomba in 2006 found that the operators of the 000 emergency line for the ambulance reacted poorly to the incident and failed to arrange effective and timely assistance for David. This has lead to some questioning as to whether 000 is really worth calling at all. BWRS still believes 000 to be only number to call in a life-threatening emergency. The reasons for this are as follows:- The problems identified in the David Iredale case were on the ambulance line. Most bushwalking emergencies are taken through the Police line and that is totally separate. There is no question as to the competence of the personel on the Police 000 line.
- The ambulance service has acknowledged the problems identified in the David Iredale case and has addressed them. In fact most of the problems were fixed years before the inquest.
- The 000 emergency line remains the only phone number guaranteed to be monitored 24 hours a day, 7 days a week, with the ability to quickly connect you to any emergency service.
- The only point BWRS would make about this case is that if a 000 operator insists on inappropriate information - for instance insisting on locating you by street and cross street when you are in a remote area and a grid reference is the only appropriate location reference - then you should ask for the operator's supervisor. The call centre supervisors are experienced emergency service workers and should quickly see if a situation is outside their normal procedures.
Satellite Phones
Satellite phones provide much broader coverage than normal mobile phones as they rely on satellites orbiting the Earth to receive the signal rather than land based antennas. Compared to normal mobile phones they are heavier, bulkier, more expensive (an average cost is $1800 up front plus $30 a month access charge, calls charged at $1.80/min) and tend to have reduced battery life. They require a location with a clear view of the sky, this means they may not work in deep valleys.000 and 112 do not work with all satellite phones.
Based on the information available on this webpage and Wikipedia 112 page I have found the following differences between the various satellite phone providers:
- The Iridium network does not support 000. It uses "767" (SOS) instead to contact an international SOS medical centre. I have been unable to find information about this service so if you plan to use Iridium phones for emergency use it is suggested you research this service and whether it is suitable. Iridium phones also require an international call for people to contact you.
- Telstra Satellite is based on the Iridium system but is set-up on the Telstra Australian system. This means it can connect to 000 and presumably 112. It also has a normal Australian phone number.
- Globalstar appears to offer the capability to contact 000 but I have not confirmed it. This phone has a normal Australian mobile phone number.
- Optus Thuraya Mobile Satellite Phone looks interesting but has not been reviewed in detail here.
- Inmarsat is a large vehicle based system which appear to be too large for bushwalking.
Two Way Radio
UHF
UHF radios provide short range and line of sight communications. The most common systems are on the UHF CB band, which are light, cheap and do not require a license to use. There is no call cost as the communication is either directly between two radios ("simplex") or two radios communicating via a repeater ("duplex"). You can expect a range of 15km in simplex mode in ideal conditions (ie a clear view of where you are communicating to such as a lookout or hilltop) with a 5 Watt radio. 5 Watts is the maximum legal power for the UHF CB band. Lower power units and obscured line of sight will reduce the useful range. I have lost communications with UHF radios in a twisting canyon in only a few hundred metres!.In general they are not good to rely on for communications in an emergency, but can be useful for communicating within a group. However, many rural properties have a UHF CB radio permanently on, so this can be a useful backup communication method if other methods have failed.
Another issue to be aware of with CB radios is that near major cities or highways there are a lot of people on these channels so you can expect to pick up other people's transmittions. Unfortunately it is common for these transmittions to use very explicit language and to be down-right crude. If you are easily offended or have children nearby you might want to keep the radio off until you are in a remote area and the "chooks" are out of range.
If you are in distress near rural properties and have a UHF CB radio, try every channel asking for help and waiting to see if you get a response. In my experience, most rural properties use a channel in the range 10 to 20 so this range of channels is a good place to start. Also you may be able to reach a repeater on duplex mode on one of the channels 1 through to 8. You can test if you are being received by a repeater by briefly tapping the push-to-talk button (PTT - no need to say anything) and wait a few seconds. If a repeater is in range it will reply with its identification code as a Morse code message. Repeaters send their ID every minute while there is activity on that channel. If you hear nothing then wait 60 seconds and repeat. If you still hear nothing then no repeater can hear you on that channel. If you do reach a repeater it will re-broadcast your message with increased power which will extend the range over which somebody might hear your transmittion.
Channel 5 in duplex mode is commonly an emergency channel, however this cannot be relied on and there is no guarantee that anybody is monitoring it.
27MHz CB
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There is a second CB band in Australia (CB means common band, which means access is unrestricted and no license is required). This is known as 27MHz CB. As for UHF CB radios, no license is required to use a radio in this band and radios are easily available and relatively cheap. In comparison to UHF CB, the 27MHz CB radios tend to be a little larger and heavier, have reduced voice quality, but have longer ranges and the signal can bend around obstructions better than UHF CB.This system is less common than UHF CB and is almost never monitored for emergency transmittions. This makes it a poor choice as an emergency communications system.
HF
HF radios provide long range communications person to person, or person to base. Compared to UHF units they are more expensive, bulkier, heavier and require a license (for example, $100 a year at http://www.vks737.on.net). There is no call cost. HF radios do not necessarily require line of sight for communications as the radio signal has two properties which allow it to bend around terrain:- The signal has a "ground wave" which follows the ground, including following undulations for a short distance (1-5km depending on conditions) from the transmitter.
- The signal has a "sky wave" which travels high into the atmosphere - the ionosphere in fact - where for a narrow band of frequencies in the HF spectrum the atmosphere bends the signal back to Earth. This means the ionosphere acts as a mirror and reflects the signal back to Earth. This technique is commonly used to bounce HF signals around the world if the signal is sent at an angle. If the signal is sent straight up it reflects back down again in the local area - this technique is called "near vertical incidence sky wave" or NVIS - and this is the technique BWRS uses during search and rescue operations to get radio communications out of canyons and over mountain ranges.
Effective use of an HF radio requires considerable knowledge and training, but if you are keen to do the required work to understand the operation of the device it can be a very powerful tool. There are also a number of services on HF which may be useful in remote areas, such as weather forecasts and radiophone systems (these allow you to connect an HF radio into the standard telephone network.
UHF Radio Beacon
A system supplied by the Tracme company is a UHF beacon. It is:
- very small (use it as a keyring)
- light
- waterproof
- and cheap (RRP $99 but can be found for $49)
- It transmits the message "Help...Emergency" continuously every 15 seconds. You cannot transmit any other information.
- It transmits on UHF CB Channel 5. While this is nominally the emergency UHF channel it is rarely monitored by emergency services and is therefore unreliable to contact emergency services by this method.
- Emergency services do not monitor this channel even when there is a search occuring. It would only be monitored if it was known the missing party had one of these units.
- Its transmit power is 0.01W. This is very low and will mean the signal will have a short range and be quickly attenuated by foliage or any other obstruction.
- The system will only work when a receiving station has line of sight to the tracme and is within a short range - the tracme website claims the range in light forest is 1km.
Personal GPS Tracker
A number of systems have been developed which use a GPS to evaluate your current position and transmit that to a satellite. One example is the SPOT system. The system allows 4 levels of message to be transmitted:
- Alert 911 - Emergency services are contacted and sent to your location (I have not yet confirmed this feature works in Australia)
- Ask for help - Your nominated people are contacted and informed of your location and that you require assistance. This is for non-life threatening situations when you just need the assistance of some friends.
- Check in - Your nominated people are contacted and informed of your location. This is to show your location and all is well.
- Track me - Every 10 minutes your location is transmitted to SPOT and linked to a Google Maps web page showing your movements.
This is a very interesting system and has many useful features. Specifically:
- It uses satellite communication so sill work a long way from populated centres. However like most satellite systems it requires a relatively unobstructed view of the sky to work.
- BWRS has investigated the units in 2008 and found that they used older style GPS engines which tend to be slow and have difficulty getting a good fix in tree cover. We understand the 2010 SPOT system has been updated to a current generate GPS engine and should therefore have far superior GPS accuracy and reliability.
- It allows people at home to track your progress. This is a big comfort for some people!
- It allows several levels of response. If all you need is for your mother to bring you lunch you can contact her directly and leave the emergency services for the real rescues!
- Be aware that at the time of writing I have not managed to confirm the SPOT system works with the 000 system in Australia. This would need to be confirmed before this system could be recommended for use in emergency communications.
- The SPOT system has two puzzling issues:
- You can only transmit your position or a choice of a few pre-prepared messages. It is not possible to write your own message
- Even though the system uses a GPS, it does not display the GPS position so if you are using a GPS for navigation you will need to also include your normal GPS.
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