The National Transit Database (NTD) has been established to be the United States’ primary source of transit system information and statistics. The NTD reporting system has evolved from the Uniform Financial Accounting and Reporting Elements Project (Project FARE) to assess the continued progress of the nation’s public transportation systems. The system derives data from transit providers, States, or Metropolitan Planning Organizations (MPOs) that are recipients and beneficiaries of grants. There are 55 data fields that are collected from six different forms for safety and security. Data are available online from 2002 to 2013. NTD safety and security data focus on data by mode and by agency. Modes include the following:

• Automated Guideway: A rail system operating on a single track and without an operator. Changed to MG in January 2012.
• Commuter Bus: Fixed-route bus systems that are primarily connecting outlying areas with a central city. Service typically uses over-the-road buses with service predominantly in one direction during peak periods, limited stops, and routes of extended length. Started in 2012 (previously reported as MB).
• Cable Car: A unique rail system in San Francisco, CA operating on cables located underneath streets.
• Demand Response: Shared-ride transportation service operating over regular streets and roads, but not according to fixed routes. Commonly called "paratransit" service.
• Demand Response-Taxi: A special form of the demand response mode operated through taxicab providers.
• Ferryboat: Shared-ride transportation service for persons operated on waterways.
• Inclined Plane: A rail system using cables for operating on steep slopes. Also known as a "funicular."
• Heavy Rail: A rail system operated on completely exclusive guideway, with no grade crossings for vehicles or pedestrians. Systems often support long trains of 6-8 cars, and typically have level-platform boarding. Commonly called "subways" or "rapid rails."
• Jitney: Shared-ride transportation system using owner-operated vehicles on regular streets and roads according to fixed routes, but not necessarily according to fixed-schedules.
• Light Rail: A rail system operating on local routes with relatively frequent stops, and one or more grade crossings for vehicles or pedestrians. Systems often use shorter trains of 2-4 cars, and are typically powered by overhead wires. Light Rail includes both streetcars, and rapid light rail systems which may have extensive stretches of exclusive guideways, including tunnels/subways.
• Motor Bus: Shared-ride transportation service operating over regular streets and roads, according to fixed routes. Vehicles are powered by an on-board motor, and are not owner-operated.
• Monorail/Guideway: An electric railway that straddles a single guideway. It may have vehicle operators or may use computers to guide the vehicles. Started in 2012 (previously reported as MO or AG)
• Monorail: A rail system operating on a single rail and with an on-board operator. Changed to MG in January 2012.
• Público: The jitney system operating in Puerto Rico.
• Bus Rapid Transit: Fixed-route bus systems that combine passenger stations, traffic signal priority or pre-emption, low-floor vehicles or level-platform boarding, and separate branding of the service. This is often a lower-cost alternative to light rail. Started in 2012 (previously reported as MB).
• Streetcar Rail: Rail systems operating routes predominantly on streets in mixed-traffic. This service typically operates with single-car trains powered by overhead catenaries and with frequent stops. Started in 2012 (previously reported as LR).
• Trolleybus: Shared-ride transportation service operating over regular streets and roads, according to fixed routes, and powered by overhead wires. Does not include historic or replica "trolleys" powered by on-board motors.
• Aerial Tramway: Transportation of passengers provided in a car suspended from overhead wires.
• Vanpool: Shared-ride transportation service in which one of the riders operates the vehicle. Pools of riders are arranged by a public transportation provider and are open to the public. The driver may receive some in-kind benefits such as free or reduced fares and/or limited personal use of the vehicle.
• Hybrid Rail: Rail systems primarily operating routes on the National system of railroads, but not operating with the characteristics of commuter rail. This service typically operates light rail-type vehicles as diesel multiple-unit trains (DMU’s). Started in 2012 (previously reported as LR or Commuter Rail)

Note that there are several excluded modes. Commuter Rail and Alaska Railroad modes are excluded from this analysis. Additionally, Heavy Rail service reported for Port Authority Trans Hudson, Hybrid Rail service for the Tri-County Metropolitan Transportation District of Oregon, and Hybrid Rail service for Capital Metropolitan Transportation Authority are excluded because they report safety data to the Federal Railroad Administration.

NTD safety and security data include the following:

• NTDID: The four-digit number that is unique to each transit system reporting to the NTD. The first digit represents the FTA Region #, with "0" for Region 10. The remaining three digits are assigned sequentially.
• Agency: The name of the system.
• Mode: A two-letter code assigned to the mode of service operated.
• TOS: Type of Service: a two-letter code describing the type of service operated. "DO" = directly operated service. "PT" = purchased transportation (i.e. "contracted out") service.
• City: The city where the system's headquarters are located.
• State: The State where the system's headquarters are located.
• UZA: A numeric code assigned to the Census-designated Urbanized Area in which the system primarily operates. Numbers are assigned sequentially from the largest UZA (#1 = New York-Newark, NY-NJ-CT) to the smallest (#452 = Fond du Lac, WI), with exceptions made for UZAs in Puerto Rico (numbered from #500-#511), the special Virgin Islands UZA (only applies to FTA grants, numbered #600), and one UZA that was added after the initial UZA definitions were published (#453 - Cumberland, MD-WV-PA).
• UZA Name: The name of the Census-designated Urbanized Area in which the system primarily operates.
• DRM: Directional Route Miles: The number of miles of fixed-guideway service in each direction operated by a transit system. A single mile of track or roadway in which trains or buses operate in both directions is 2 DRM. A mile in which three tracks are laid in parallel, but in which trains only operate in two directions is also 2 DRM.
• TWM: Trackway Miles: The number of miles of fixed-guideway on which the system operates, regardless of direction and regardless of whether it is parallel to other fixed guideway.
• UPT: Unlinked Passenger Trips: The number of boardings on transit vehicles reported by the system in its own fiscal year corresponding to the year listed.
• PMT: Passenger Miles Traveled: The number of miles traveled by passengers reported by the system in its own fiscal year corresponding to the year listed.
• VRM and Passenger Car Miles: Vehicle Revenue Miles: The number of miles traveled by transit vehicles in revenue service, as reported by the system for its own fiscal year corresponding to the year listed. For rail modes, "passenger car revenue miles" is used.
• Train Revenue Miles: Train Revenue Miles: The number of miles traveled by whole train vehicles in revenue service, as reported by the system for its own fiscal year corresponding to the year listed.
• VRH: Vehicle Revenue Hours: The number of hours operated by transit vehicles in revenue service, as reported by the system for its own fiscal year corresponding to the year listed.

VOMS: Vehicle Operated in Maximum Service: The number of vehicles operated in peak scheduled service by the system, as reported by the system for its own fiscal year corresponding to the year listed.
Incidents:

• Collision_Total: Total number of collisions reported to NTD.
• Derailment_Total: Total number of derailments reported to NTD.
• Security_Total: Total number of major security incidents reported to NTD.
• Fire_Total: Total number of fires reported to NTD.
• NOC_Total: Total number of accidents "not otherwise classified" (NOC) reported to NTD. These events include slips, trips and falls; electric shocks; suicides; vehicles leaving roadway; and other events that are not reported as a collision, derailment, or fire.
• Incident_Total: Total number of incidents reported to NTD.

Fatalities/Injuries:

• Passenger: Number of passengers killed/injured. Passengers include individuals onboard a transit vehicle.
• Rev Fac Occupant: Number of revenue facility occupants killed/injured. Revenue facility occupants include individuals waiting for or leaving transit.
• Operator: Number of transit operators killed/injured. This data point is not collected prior to 2008.
• Employee: Number of other transit employees killed/injured. This data point is not collected prior to 2008.
• Total Employee: Sum of "Operator" and "Employee."
• Other Worker: Number of other workers (non-transit) killed/injured.
• Bicyclist: Number of cyclists killed/injured. This data point is not collected prior to 2008.
• Ped In Crossing: Number of pedestrians in crosswalks killed/injured. This data point is not collected prior to 2008.
• Ped Not In Crossing: Number of pedestrians not in crosswalks killed/injured. This data point is not collected prior to 2008.
• Ped Crossing Tracks: Number of pedestrians crossing tracks killed/injured. This data point is not collected prior to 2008.
• Ped Walking Along Tracks: Number of pedestrians walking along tracks killed/injured. This data point is not collected prior to 2008.
• Other Vehicle Occupant: Number of occupants of other vehicles killed/injured. This data point is not collected prior to 2008.
• Other: Sum of "Bicyclist," "Ped in Crossing," "Ped Not In Crossing," "Ped Crossing Tracks," "Ped Walking Along Tracks," and "Other Vehicle Occupant."
• Trespasser: Number of trespassers killed/injured.
• Suicide: Number of suicide-related fatalities/injuries.
• Total Other: Sum of "Other," "Trespasser," and "Suicide."
• Total Fatalities/Injuries: Sum of "Passenger," "Rev Fac Occupant," "Total Employee," "Other Worker," and "Total Other"

There are six NTD Safety and Security Reports, which include the major incident report form and non-major safety monthly summary report form. All major incidents must be reported within 30 days of the incident, and safety monthly summaries of incidents are due at the end of the following month. Annual safety and security reports are due within 31 days of the end of the calendar year. The guidelines for reporting incidents provide specific examples of how to report uncommon incidents. Note that not all incidents are considered to be reportable. If an incident is not related to and does not affect revenue operations, then it is considered to be non-reportable.