POLICY STATEMENT
AUDIBLE TRAFFIC SIGNALS
Adopted by National Convention
June 1994
PREAMBLE
1. In recent years Blind Citizens Australia has played the leading role in the promotion of the benefits of audible traffic signals and has advocated for their installation, firstly in Victoria and then throughout Australia. Audible traffic signals have made a major contribution to the safe and independent travel of blind people in the community. As the major users of audible traffic signals, it is important that the views of blind people continue to influence their use and development.
2. Blind Citizens Australia, as Australia's national organisation representing blind people, adopts the following Policy Statement regarding audible traffic signals. Blind Citizens Australia Members, Branches and Organisational Members are called upon to implement this policy locally by seeking a greater role for themselves in decisions made by the relevant local authorities, as to the location of audible traffic signals and the type and sound of signals to be used. Blindness agencies, particularly those which provide orientation and mobility services, are requested to use their influence to persuade relevant authorities to implement this Policy. Blind Citizens Australia Council is requested to give priority to the adoption of this Policy as a National Standard for audible traffic signals through the Australian Standards Association, and its implementation by relevant State, Territory and Local Government Authorities.
3. In this Policy the term "blind people" includes both people who are totally blind and people whose degree of vision impairment affects their ability to travel safely and independently.
SITES AND THEIR SELECTION
4. Audible traffic signals which meet the standards implied in this Policy should be installed on all poles at all sites where visual traffic signals are installed. A set budget allocation should be earmarked each year for this purpose. It should be Government policy to install audible traffic signals whenever visual traffic signals are installed. Sites for the installation of audible traffic signals should be selected on the basis of consumer demand, i.e. in consultation with blind people and their representative consumer organisations. Sites should not be selected only on the basis of pedestrian counts or traffic usage. Governments should not select particular types of sites to the exclusion of others, e.g. sites where all traffic flow is stopped and pedestrians walk in both directions.
INSTALLATIONS
5. Audible traffic signals should emit a slow beat for "don't walk" and a fast beat for "walk". Signals should emit a sound at all times and should not need to be activated by the pressing of a button. The sound of the signal should be clearly audible from a distance of 8 metres, and should comply with the national standard as to volume and frequency. In areas in which Blind Citizens Australia Branches or Organisational Members exist, they should be consulted as to proposed installation sites and the types of signals and sounds to be used.
6. The components of an audible traffic signal should comply both in structure and performance with the relevant Australian Standards. These are currently: AS1742.10 Clause 12 "Provisions for Disabled Pedestrians", and AS2353 of 1992 "Pedestrian Push Button Assemblies" Clause 10 "Audible Signals". Copies of the relevant clauses of these Standards are attached to and form part of this Policy.
MAINTENANCE
7. A set amount should be earmarked in each budget for the maintenance of audible traffic signals as part of the allocation for the maintenance of visual traffic signals. The audible traffic signals should receive priority in maintenance. Authorities should publicise a telephone number to which faults may be reported, and they should have faults rectified promptly.
8. Audible traffic signals should be switched on and be operative 24 hours a day. If an authority finds it necessary to turn off the sound (e.g. for maintenance), affected blind people should be advised in advance, if practical, through their organisations and via radio announcements. Where installations are within 50 metres of houses, the sound may be turned down but not off.
EXTRACT FROM AS2353
AUSTRALIAN STANDARD
PEDESTRIAN PUSH-BUTTON ASSEMBLIES
10 AUDIBLE SIGNALS
10.1 _General _requirements Where required, facilities shall be provided for the generation of audible signals in accordance with Clauses 10.2 and 10.3. Components utilised in the provision of the audible signals shall be rated for operation within the temperature range of -10C to 65C.
NOTES:
1 The purchaser must specify whether facilities for the generation of audible signals are required (See Item C), Appendix A). The device generating the audible signal need not be an integral part of the pushbutton assembly but, where separate, it should be installed on the same traffic signal post.
2 The characteristics of the audible signal should take into account
(a) requirements for auditory localisation;
(b) the prevalence of frequency-dependent hearing impairment;
(c) masking of signals by ambient noise; and
(d) adverse environmental effects, e.g. noise pollution.
See HULSCHER, F.R., Traffic signal facilities for blind pedestrians, Proceedings of Australian Road Research Board, 1976, Vol. 8, Pt 5.
3 A fail-safe arrangement should be provided between the visible and the audible signals to ensure that no conflicting indications can arise.
10.2 _Required _characteristics Provision shall be made for the generation of two types of audible signal, namely:
(a) a "WALK" signal having a repetition rate of between 8Hz and 16Hz; and
(b) a "DON'T WALK" signal having a repetition rate of between 0.5Hz and 1Hz.
The peak A-weighted sound pressure level of the audible signals shall not exceed 85dB (relative to #bj.m,pa,7 in any direction, when measured under the conditions specified in Clause 10.3. Facilities shall be provided for adjustment of the sound pressure level up to a setting which just ensures compliance with a specified maximum.
10.3 _Measurement _conditions The sound pressure levels of the audible signals shall be measured:
(a) with the assembly mounted in the manner for which it is designed;
(b) under free-field conditions;
(c) using a sound level meter complying with the requirements for Type 1 meters specified in AS1259, with frequency-weighting characteristic A and time-weighting characteristic P; and
(d) at a distance of 1m from the assembly, and 1.5m above ground.
12 PROVISION FOR DISABLED PEDESTRIANS
12.1 _General General information about providing services for the disabled is given in AS1428. In addition, the following points should be specifically considered when providing for disabled pedestrians.
12.2 _Curb _crossings Curb crossings should be provided without a drainage lip. Where pedestrian refuges are provided the crossing point should not have curbing but should be at the same level as the adjacent carriageway. For the design of curb crossings for disabled pedestrians see AS1428.
12.3 _Audio-_tactile _signals Visually handicapped pedestrians can be assisted to locate pedestrian actuated signals, and to know when the pedestrian phase is operating, by the installation of audio-tactile devices in the pedestrian button assembly. These devices emit an audible clicking sound and may include a tactile pulse. During the pedestrian phase the device operates at a much higher frequency than when in its resting mode thus providing a clear message to the visually handicapped person.
12.4 _Tactile _paving Tactile paving has been designed for use on footpaths and refuges in the vicinity of crossings to impart information to the blind or poorly sighted by means of a specially textured surface. The texture has three functions:
(a) it helps blind people find the crossing point;
(b) in the case of crossings having pedestrian signal control it helps blind people find the pedestal carrying the pedestrian push- button; and
(c) it enables blind people, while waiting to cross, to align themselves in the direction in which they should proceed.
The last function is of particular importance where a ramp and dropped curb have been provided for the benefit of wheelchair users and people with baby carriages, as the blind person no longer has the benefit of a raised curb to provide this cue.
The surface used for this purpose has to meet several requirements. It must be detectable underfoot, because guide-dogs and long canes are searching for obstacles rather than for changes in the surface; and it must be reliably detectable even to people wearing thick soled shoes or those who suffer from reduced sensitivity in their feet. It should be simple and cheap to install and maintain, should contrast in colour from adjacent surfaces, and needs to be distinct from surfaces used for other purposes.
A number of textured paving bricks or tiles are now available. One type has a grid pattern of raised nodules, either on a brick or on a flat tile. The other type has parallel ridges running across the brick or tile.
At pedestrian refuge islands, two or three rows of textured slabs should be laid across the pedestrians' path through the island flush with the carriageway surface.
Wherever it is proposed to install textured surfaces, local organisations representing disabled people should be consulted.