Audible and Visual Warnings PDF

Audibib and Visual Warnings Learning outcomes By the end of this chapter you should: Understand the purpose and use of passive visual warnings. Understand the pijrpose and use of active visual warnings. Understand the purpose and use of audible warnings....

Audibib and Visual Warnings Learning outcomes By the end of this chapter you should: Understand the purpose and use of passive visual warnings. Understand the pijrpose and use of active visual warnings. Understand the purpose and use of audible warnings. Recognise *the benefit of alternating siren tones. Know the risks associated with travelling in convoy in relation to siren use. | Recognise; when the use of emergency warning equipment (EWE) is permittejd. Recognise when EWE must not be used and when the deactivation of sirens should be considered. '6' r  Emergency Ambulance Response Driver's Handbook i The presence of an emergency vehicle often influences the behaviour of other road users and pedestrians and, for these reasons, emergency ambulances are fitted with visual or audible warnings, or both, to alert road users to your presence or approach, In this chapter we consider the active and passive visual warnings that are incorporated into ambulances, as well as their audible warnings, and the impact that they can have on other road users. / m Appearance and markings / There are two types of visual warning on an ambulance. These are passive / or active. Passive visual warnings Modern emergency vehicles are fitted with retro-reflective high contrast colour passive visual warnings, which reflect light from car headlights. Emergency ambulances are usually painted yellow to meet the requirements of the CEN 1789:2007 European Union Standard for ambulances and medical transportation vehicles (the UK equivalent is BS EN 1789:2007). The word 'ambulance' is depicted in mirror image formal on the front of the vehicle using the retro-reflective material to enable drivers in front of the approaching ambulance to identify it in their mirrors. Emergency vehicles are equipped with 'checkerboard' or 'Battenberg markings along the length of the vehicle. The colours yellow and green are reserved for use by the ambulance service only, Similarly the police may use blue and yellow, the fire and rescue service uses red and yellow and Highways England uses black and yellow. Note that in other parts of the UK the police or other agencies may take on the role of Highways England. In order for any retro-reflective material to remain effective it is important that the vehicle is kept clean. Further information regarding the correct use of retro-reflectiv e markings can be found in the Road Vehicles Lighting Regulations 1989, schedules 17 and 18. It is important to remember that the bright yellow colouring and markings on am balances may suddenly be noticed by traffic ahead of you. This can sometimes be after a prolonged period of non-observance, resulting in sudden 84  Audible and Visual Warnings or unexpected vehicle movement or braking without warning. It is therefore important that adequate following distances are maintained. Active visual warnings These warning lights commonly include flashing blue lights - white and blue strobes and LEDs fttted to the roof, front, sides and rear. Flashing headlights can be used during daylight hours. The emergency warning lights must have 360° visibility around the vehicle in order to be BS EN 1789 compliant. Blue flashing lights are only permitted to be used by services specifically defined in the Road Vehicles Lighting Regulations 1989, as amended by the Deregulation Act 2015. For flashing headlights, the majority of modern emergency vehicles have the facility to disable, or have an inbuilt feature that prevents, this type of warning light from being activated at night when the vehicle headlights are switched on. This minimises the risk of dazzling other drivers, Some ambulance services that serve the UK's airports may have airport beacons fitted to their emergency vehicles. These are yellow or amber in colour and should only be used when the vehicle is deployed at the airport's 'airside'. I Audible warnings Sirens Most modern ambulances are fitted with electronic sirens that have the benefit of alerting people to the presence of an ambulance before they are able to see it, Sirens can usually produce a range of different noises/tones that can be useful in different situations, for example: ► 'Wail' sound: characterised by a long up and down variation with an unbroken tone, the 'wail' siren is best used when traveling on a long stretch of road or in open areas. The long slow tone is spread out from the front of the vehicle in a fan shape. ► Yelp sound, this is similar to the 'wail' siren but faster, emitting the familiar 'whoo-whoo-whoo-whoo' sound. The 'yelp' siren is preferred in heavy slow traffic, at junctions and in built up areas. The fast short tones of the yelp siren bounce off buildings, cars and other structures to deflect the noise, but this can cause confusion among other road users as to the direction of approach of the emergency vehicle. 85 1 Emergency Ambulance Response Driver's Handbook ^ 'Bui! horn': a deep, single tone sound that provides a completely different, non-electronic baritone warning. This is often used to supplement the 'normal' emergency audible warning sounds, These can be useful to attract attention but should never be used in an aggressive manner. Ambulance services may specifically train their drivers to use different siren tones in different situations, so refer to your local policy. Travelling in convoy Drivers of emergency vehicles should refrain from travelling in convoy when engaged in emergency response driving, however it is accepted that this is not always possible. In the event that a number of emergency vehicles must travel together, for instance on route to a major incident or where a specialist vehicle has also been deployed, then extra care and vigilance must be taken by all drivers. Other road users may not be expecting more than one vehicle and may behave unexpectedly to your presence. If you are the following vehicle it is advisable to use a different siren tone presence to the lead vehicle, this will alert other road users to the ,, , of further vehicles. Always maintain a safe following distance and always leave enough room to be able to stop in the distance you can see to be clear, Emergency warning equipment in I practice Drivers of emergency vehicles have a duty to warn other road users of their presence and intentions by exposing, to those who would benefit, any warning equipment - visual or audible - that is fitted to the vehicle. This should be balanced against the occasions when it offers more protection to deactivate audible and visual warning equipment, for example when in standing traffic where it can be intimidating. Blue flashing lights and sirens influence the behaviour of other road users - this is due to the presence of the emergency vehicle and the urgency of the journey being undertaken, They do not give any legal entitlement to claim precedence where it is unsafe. You should also be aware at all times that if you have EWE fitted to a vehicle, the public have the right to receive the warning the equipment is designed to give. 86  Audible and Visual Warnings The nature of loud sirens may be intimidating, so they must be used intelligently in stationary traffic when there is a risk of threatening or forcing I I other vehicles to commit to a potentially dangerous manoeuvre that they may not have attempted otherwise. In this case, deactivation of the EWE must be considered (effective non-use). In the event of a solo-response driver remaining with the patient en route to the hospital (due to their advanced clinical skills, for example) one of the ambulance crew members may be asked to drive the solo -response vehicle (SRV) to the receiving hospital. When this situation arises, the SRV must not , utilise EWE and must adhere to all road traffic regulations. The SRV must not act as an escort to the ambulance. If you believe that the vehicle in front may not have heard the siren, changing the siren tone may gain their attention. However, you should refrain from repeatedly flicking between the siren tones as this may be perceived as aggressive or intimidating to the other road user. B KNOWLEDGE RECAP 1 Describe an emergency vehicle's passive visual warnings. 2 Describe an emergency vehicle's active visual warnings, 3 Different siren tones can be beneficial in different situations, When might it be preferable to use a 'yelp' setting rather than a 'wail' setting? 4 What is the best practice for the use of sirens should you find yourself travelling to an incident in convoy with other emergency response vehicles? 5 In what circumstances should the deactivation of sirens be considered and why? 87