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This research work is on pedestrian and bicyclist safety and the impact of PTAL levels upon them and when it comes to safety,pedestrians and cyclists are at an inherent disadvantage.Associations like AASHTO,TRB,ITE and ASCE are working on bicyclist and pedestrian safety.The research done on pedestrian and bicyclist safety shows key information about the type number and severity of crashing is lacking and there is also a lack of transferrable and standardized exposure data and this lack of data and studies results in inability to draw any authentic conclusion about the impact of work on pedestrian and bicyclist safety.The current technological advancements and their impact on pedestrian and bicyclist safety are also discussed.Transport for London TfL is responsible for the Transport system in London UK.Travel Time Mapping,Catchment Analysis,and PTAL are the techniques used by TfL for connectivity assessment.PTAL is an easily calculated and simple technique that hinges on the distance from any place or point to the nearest public transport stop,In total there are 9PTAL values ranging from 0 to 6 including sub values of 1 and 6,（0,1a,1b,2,3,4,5,6a,6b）.The lowest PTAL value 1a show the poor connectivity with the public transport and the highest PTAL value 6b shows best connectivity.The calculation procedure of PTAL includes the calculation of Walk-time to SAPs,Scheduled Waiting time,Average Waiting Time,Total Access Time,Equivalent Doorstep Frequency and Access Index.The finally calculated Access Index in then converted to PTAL level with the help of the table provided by TfL.The data used in our project was taken from London Data Store and the data of LSOA（Lower Service Operational Area）11 of Greater London was considered.Negative and zero inflated negative models were fitted to the three responses of Total number of accidents,total number of pedestrian accidents and total number of bicycle accidents,in order to perform model comparisons AIC and BIC information criteria were used.The highest accident counts were observed for the 6b PTAL level.IMD index was found to be significant predictor for total number of accidents and total number of pedestrian accidents but not for bicycle ones.