Railroads have served the needs of people and commerce in the United States for nearly 200 years. Since 1827, when the first steam-powered locomotive debuted, to America’s original 13-mile track and beyond, rail has been on a continuous journey of improvement. Today, approximately 139,679 miles of track facilitate the movement of 1.7 billion tons of freight each year with crew size varying by class and need.

For most of the history of freight rail, efficient movement of goods was the highest priority. While rail undoubtedly moves massive amounts of freight and hazardous materials efficiently today, the considerations competing for priority in the industry now range from climate and environmental impact to safety. These of course go hand-in-hand with efficiency.

In fact, safety is arguably the most important factor to the freight rail industry today, given that derailments mean economic goods not reaching their destination, employees and bystanders being harmed, and environmental consequences threatening whole populations and ecosystems.

Rail carriers have tackled the challenge of safety in many ways. At the most basic level, visual track inspections have been used for decades to detect flaws and issues. As technology has advanced, many of the imperceptible deficiencies have been traced by sensors and deployable technology that can continuously monitor track conditions. Drones are even used to inspect and capture information on remote areas of rail or long stretches of infrastructure from overhead in a fraction of the time that similar inspections may take personnel on the ground.

These are essential pieces of technology because the majority of derailments and rail incidents occur due to track deficiencies and infrastructure failures. A significant portion of those issues are also of a kind that the naked eye cannot discern, making technological solutions the only realistic and impactful way to ensure safety.

Human error, however, follows infrastructure and equipment flaws closely as a leading cause of tragic incidents and derailments. These are most often human oversights or misjudgments made inside the locomotive. Human error of course exists in every industry. For rail, it can be especially dangerous and deadly when the payload includes hundreds of cars of hazardous material.

A natural impulse to correct human error is to add personnel and enlarge the crew size to ensure one man’s blind spot or misjudgment is caught by another’s vigilance. This works as long as the human error is the type caused by inattention, rather than something humans altogether fail to perceive. Further, it must be something two or more people can quickly agree to, effectively resolve, or safely control.

From 2010 to 2016, leading human errors, irrespective of crew size, resulting in incidents included: over speeding, failure to obey display signals, failure to communicate with railroad operators, violation of switching or mainline rules, incorrect setting of track switches, and driver’s physical condition including fatigue, vision, or impairment reaction.

Technology, however, may offer a way to see through blind spots, process data faster, and communicate more robustly than humans are capable. This brings up the question of whether humans should be required to man the train in pairs or groups in order to prevent issues and if that alone could effectively achieve safety outcomes.

The question of crew size for rail has confounded industry participants for years. How many people are needed to safely operate a train? How many people is one software package worth?

Many argue advancements in technology should only be a supplement to human control, management, and oversight. This would mean that technology bolsters the eyes and ears of the conductor, rather than replace him. This is hardly objectionable. The argument gets less clear when mandatory minimum crews of two or more are proposed.

If technology and innovative automation are able to communicate directly with other infrastructure faster and ahead of when a human can know of upcoming information, why should two or more people be mandated to manage the safe operation of the train?

One of the key pieces of technology for promoting safe rail operation is Positive Train Control (PTC), which encompasses hundreds of thousands of components continuously sharing information throughout an interconnected network of rail infrastructure to facilitate train-to-train, train-to-station, and other inter-infrastructure communication. These interconnections and signals were precisely designed to address human error. PTC is even able to fully stop a train if human intervention fails to react to the information provided.

According to the Federal Railroad Administration, the technology is useful for preventing train-to-train collisions, excessive speed derailments, train incursions into active maintenance or work zones, and movement of a train through track switches left in the wrong position. PTC systems continuously determine the location, direction, and speed of trains in order to warn train operators of potential problems, and in the absence of a human decision, bring the train to a halt. These features naturally implicate human crew sizes. PTC is able to keep a train operating safely and bring it to a stop if an incident is anticipated, yet it was designed to feed information to a human, not to replace a crew. This is where the nuance of the debate becomes contentious, how many people should be required to work with PTC to keep the train safe?

Importantly, one position argues that there should be mandatory crew sizes of two or more people, but the other position does not argue for zero or only single-person crews. The argument against mandatory minimum crews of two or more is twofold: first that the discussion should be guided by data and the safety record, and second, that crew sizes and personnel decisions should be left to the carriers either through individual contracts or collective bargaining.

There is little data to support that mandatory minimum crew sizes of two or more objectively result in safer outcomes. With PTC now fully implemented across the entire 57,536-mile congressionally mandated rail infrastructure, including embedded throughout approximately 20,000 locomotives, human error is significantly decreased.

The clear correlation in the last two decades has been that a rise in technology has led to a reduction in derailments, accidents, injuries, and deaths. This cannot all be credited to PTC, as technological advancements and automation in track inspections and geometry have greatly improved track safety. Data does demonstrate that human errors are mitigated through innovation and automation – both inside the locomotive and across the entire rail system of infrastructure.

Those tasked with assessing rail safety must be able to separate the issues. Rejecting mandatory minimum crew size is not rejecting human operation. Safety should be assessed and governed by data, and the data seems to suggest that technology is able to safely assist at least a single person. Unless robust data is clearly presented showing added crew capacity is needed for safety, this should be rejected as a basis for regulating crew sizes. That data is virtually impossible to come by, given it would take place against a backdrop of incredible technological deployment. Government should reject crew size mandates, because as long as the trains operate safely, as they have with technological assistance, crew sizes are an employment decision, not a safety one.


Written by Benjamin Dierker, Director of Public Policy


The Alliance for Innovation and Infrastructure (Aii) is an independent, national research and educational organization. An innovative think tank, Aii explores the intersection of economics, law, and public policy in the areas of climate, damage prevention, energy, infrastructure, innovation, technology, and transportation. (Aii.org)