YD/T 2099-2010 Information accessibility - Technical requirements for deaf assistant system in public place
1 Scope
This standard specifies the technical requirements for the information accessibility deaf assistant system in public place, including the technical requirements for the hearing aid
loop system and the flashing vibration reminder system.
This standard applies to information accessibility deaf assistant system in constructive public places.
2 Normative references
The following documents contain provisions ,which through reference in this text constitute provisions of the standard. For all dated reference documents, all of their subsequent
modification forms (excluding erratum contents) or revised editions are not applicable to this standard, however, all parties reaching agreement according to this standard are encouraged
to study whether the latest editions of these documents can be used. For undated references, the latest edition of the normative documents referred to applies. The latest version of an
undated reference documents apply to this standard.
3 Terminology and Definitions
The following terminology and definitions apply to this standard.
3.1 Public Place
provision of places for mass collective activities , including stadiums, hospitals, cinemas, theaters, parking lots, conference rooms, train stations, bus stations, subway stations,
ticket offices, information desks, bank counters, hotel lobbies, schools, post offices, supermarkets, tourist spots, museums, courts, and other places where public crowds are
concentrated.
3.2 Information Accessibility
access to and use of information should be equally accessible and cost-effective for different groups of people, so that anyone can access and use information under any circumstances, in
an equal, accessible and accessible manner, using the usual means of communication.
3.3 Reference Magnetic Field Strength Level
the magnetic field strength generated by the current passing through the wire, 0dB the basemagnetic field strength level is 400mA/m(milliampere per meter).
The long-term average output power value of a magnetic field should be 100mA/m.Not less than 70mA/m above 140mA/m .The value is measured at 1.2m (sitting)in the loop and 1.7m
(standing)on the straight surface of the field. The peak intensity of up to 400mA/m is allowed in speech, and the frequency range should cover 100Hz െ 5000Hz.
3.4 Automatic Gain Control
a method of automatically controlling the gain of an input signal or other signal parameters in an amplifier circuit.
The close-loop circuit for this function is a negative feedback system, which can be divided into gain controlled amplification circuit and control voltage forming circuit. The
gain-controlled amplifier circuit is located in the forward amplifier, and its gain varies with the control voltage. The basic components of the control voltage forming circuit are the
AGC detector and the low-pass smoothers, sometimes including components such as door circuits and DC amplifiers.
Amplifying the output signal of the circuit Uo after checking the wave and filtering the low frequency modulation components and noise, the voltage Uc used to control the gain controlled
amplifier. When the input signal Ui increases , Uo and UC increases, Uc increases the amplification circuit gain decreases, so that the output signal changes significantly less
than the change of the input signal, for the purpose of automatic augmentation control.
4 Technical Requirements for Hearing Aid Loop System
Contents
Foreword
1 Scope
2 Normative references
3 Terminology and Definitions
3.1 Public Place
3.2 Information Accessibility
3.3 Reference Magnetic Field Strength Level
3.4 Automatic Gain Control
4 Technical Requirements for Hearing Aid Loop System
4.1 Overview
4.2 System Functions
4.4 System Deployment Method
4.5 System Deployment Requirements
4.6 System Inspection and Testing Requirements
5 Flash Vibration Reminder System
5.1 System Functions
5.2 System Components
5.3 Trigger Group
5.4 Flash Vibrate Group .
5.5 Deployment Requirements
1范围
本标准规定了公共场所聋人信息无障碍辅助系统技术要求，其中包括助听环路系统技术要求和闪光振动提示系统技术要求。
本标准适用于在公众场所建设的聋人信息无障碍辅助服务系统。
2规范性引用文件
下列文件中的条款通过本标准的引用而成为本标准的条款。凡是注日期的引用文件，其随后所有的修改单(不包括勘误的内容)或修订版均不适用于本标准。然而，鼓励根据本标准达成协议的各方研究是否可使用这些文件的最新版本。凡是不注日期的引用文件，其最新版本适用于本标准。
3 术语和定义
下述术语和定义适用于本标准。
3.1公众场所 Public Place提供群众性集体活动的场所，包括体育场馆、医院、影剧院、会场、会议室、火车站、汽车站、机场、地铁站、售票处、询问处、银行柜台、酒店大堂、学校、邮局、超市、旅游点、博物馆、法院等公众人群集中的场所。
3.2
信息无障碍 Information Accessibility信息的获取和使用应对于不同的人群应有平等的机会和差异不大的成本，使任何人在任何情况下都能平等地、方便地、无障碍地使用通常的信息沟通手段获取并使用信息。
3.3
基准磁场强度级 Reference Magnetic Field Strength Level
电流通过导线所产生的磁场强度，OdB 基准磁场强度级为400mA/m(指每米毫安培)。一个磁场的长期平均输出功率值应为100mAm。不得低于70 mA/m或高于140 mAm。该值是在回路内，距离地板1.2m(坐态)时测得和1.7米时(立态)的磁场垂直面上的强度。允许在言语中出现达到400mA/m的强度峰值，频率范围应当覆盖100Hz~5kHz。
3.4
自动增益控制Automatic Gain Control(AGC)
在放大电路中根据输入信号或者其他信号参数的大小而自动控制其增益的一种方法。
实现这种功能的闭环电路是一个负反馈系统，它可以分成增益受控放大电路和控制电压形成电路两部分。增益受控放大电路位于正向放大通路，其增益随控制电压而改变。控制电压形成电路的基本部件
4助听环路系统技术要求
4.1 概述
助听环路系统是为助听器使用者和听力下降者提供信号的一种装置，广泛应用于装有感应拾音线图的助听器或耳机使用。以减少由于与声源距离较远，与讲话者之间有屏蔽窗或背景噪声大而引起的聆听困难，为听力损伤者提供便利和服务。
公共场所中铺设了助听环路系统的区域内设置提示标志，如见图1所示，听障者看到该提示标志可将装有感应拾音线圈的助听器或耳机调节到相应档位(T档)，以便接收助听环路信号。
