Public Transport Accessibility Levels

<p>Transport for London's (TFL) Public Transport Accessibility Levels (PTALs)</p> <p>PTALS are a detailed and accurate measure of the accessibility of a point to the public transport network, taking into account walk access time and service availability. The method is essentially a way of measuring the density of the public transport network at any location within Greater London.</p> <p>Each area is graded between 0 and 6b, where a score of 0 is very poor access to public transport, and 6b is excellent access to public transport.</p> <p>The current methodology was developed in 1992, by the London Borough of Hammersmith and Fulham. The model has been thoroughly reviewed and tested, and has been agreed by the London Borough-led PTAL development group as the most appropriate for use across London.</p> <p>The measure therefore reflects:</p> <ul> <li>Walking time from the point-of interest to the public transport access points;</li> <li>The reliability of the service modes available;</li> <li>The number of services available within the catchment; and</li> <li>The level of service at the public transport access points - i.e. average waiting time.</li> </ul> <p>It does not consider:</p> <ul> <li>The speed or utility of accessible services;</li> <li>Crowding, including the ability to board services; or,</li> <li>Ease of interchange.</li> </ul> <p>The PTAL methodology was developed for London where a dense integrated public transport network means that nearly all destinations can be reached within a reasonable amount of time. Research using the ATOS (Access to Opportunities and Services) methodology shows that there is a strong correlation between PTALs and the time taken to reach key services – i.e. high PTAL areas generally have good access to services and low PTAL areas have poor access to services.</p> <p><strong>Notes</strong></p> <p>6-digit references identify 100m grid squares.</p> <p>The 2015 files are available to download below. This includes the GIS contour files.</p> <p>Current PTAL values can be viewed on <a href="https://tfl.gov.uk/info-for/urban-planning-and-construction/planning-with-webcat/webcat">TfL’s web site</a>.</p> <p>We also invite you to visit <a href="http://www.tfl.gov.uk/webcat">WebCAT</a>: TfL’s Web-based Connectivity Assessment Toolkit. Through an interactive mapping interface users can view for any location in London, PTAL values as well as travel time plots. Associated with the travel time plots users can also select bar charts showing catchment statistics (for example, population, jobs or services) using the same travel time bands as displayed on the map. Watch the video below for more information.</p> <table style="display: table !important;" border="0" width="100%" cellspacing="0" cellpadding="1"> <tbody> <tr> <td align="center" width="100%"><iframe src="https://www.youtube.com/embed/FPIIPWW5V3c" width="560" height="315" frameborder="0" allowfullscreen="allowfullscreen"></iframe></td> </tr> </tbody> </table><p>伦敦交通局（Transport for London, TfL）公共交通可达性等级（Public Transport Accessibility Levels, PTALs）</p><p>PTALs是对某一点位通往公共交通网络的可达性进行详细且精准衡量的指标，其考量因素包括步行接驳时长与服务供给情况。该方法本质上是用于测算大伦敦区域内任意点位的公共交通网络密度。</p><p>所有区域的评分区间为0至6b，其中评分为0代表公共交通可达性极差，评分为6b则代表可达性极佳。</p><p>现行的评价方法于1992年由伦敦哈默史密斯和富勒姆自治市（London Borough of Hammersmith and Fulham）制定。该模型经过全面的评审与测试，已获得由伦敦各区牵头的PTAL开发工作组认可，成为适用于全伦敦的最优评价方法。</p><p>该指标的考量维度包括：</p><ul><li>从目标点位步行至公共交通接驳点的耗时；</li><li>可使用的交通服务模式的可靠性；</li><li>服务覆盖范围内的运营班次数量；</li><li>公共交通接驳点的服务水平，即平均候车时长。</li></ul><p>该指标未纳入以下考量因素：</p><ul><li>可使用交通服务的运行速度或实用效能；</li><li>客流拥挤程度，包括能否顺利搭乘公共交通；</li><li>换乘便捷程度。</li></ul><p>PTAL评价方法专为伦敦打造，得益于伦敦密集且一体化的公共交通网络，几乎所有目的地均可在合理时长内抵达。采用ATOS（Access to Opportunities and Services，获取机遇与服务）方法开展的研究表明，PTALs与抵达关键服务设施的耗时存在显著相关性：即PTAL评分较高的区域通常公共交通可达性较好，评分较低的区域则可达性较差。</p><p><strong>备注</strong></p><p>6位数字编码用于标识100米见方的网格单元。</p><p>2015版数据集文件可在下方下载，其中包含地理信息系统（Geographic Information System, GIS）等高线文件。</p><p>当前的PTAL评分可在<a href="https://tfl.gov.uk/info-for/urban-planning-and-construction/planning-with-webcat/webcat">伦敦交通局官网</a>查询。</p><p>此外，欢迎您访问<a href="http://www.tfl.gov.uk/webcat">WebCAT</a>：伦敦交通局推出的基于网页的连通性评估工具包。用户可通过交互式地图界面，查询伦敦任意点位的PTAL评分以及出行时长分布图。配合出行时长分布图，用户还可选取柱状图，查看与地图上展示的出行时段区间一致的服务覆盖范围统计数据（例如人口、就业岗位或服务设施数量）。您可观看下方视频了解更多详情。</p><table style="display: table !important;" border="0" width="100%" cellspacing="0" cellpadding="1"><tbody><tr><td align="center" width="100%"><iframe src="https://www.youtube.com/embed/FPIIPWW5V3c" width="560" height="315" frameborder="0" allowfullscreen="allowfullscreen"></iframe></td></tr></tbody></table>