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TTD and Union Pacific disagree over safety technology deployment

Debate looks at role wheel temperature detectors should play in inspections

The Federal Railroad Administration is considering a waiver extension request from Union Pacific. (Photo: Shutterstock/snvv18870020330)

The debate about how to manage visual inspections in the face of advances in safety technology continues. This time it’s railroad carmen defending the importance of visual inspections for brake testing and maintenance.

Union members are responding to Union Pacific’s request to the Federal Railroad Administration to extend a waiver governing UP’s test program for wheel temperature detectors (WTDs). 

UP (NYSE: UNP) is asking FRA to allow the use of WTDs on intermodal trains operated on segments of UP’s system, as well as extend the distance at which visual inspections would be performed. UP has been using WTDs under normal operating and traffic conditions between the coal mines of Wyoming’s Powder River Basin and an unloading facility at White Bluff, Arkansas. 

But union members say UP’s goal is to reduce visual inspections and save on overhead costs.


WTDs are “actually a useful device that’s clearly valuable as a complement to the inspections, but [the technology is] really about detecting the temperature on the rail,” Regan told FreightWaves. WTDs have “to be used as a complement to the inspections. A person is trained to see where there might be a defect, where there could be a problem down the road and what might need to be improved or upgraded or replaced in the near future. This device cannot do that.”

TTD also argued in a February letter to FRA that UP failed to gather and provide any evidence for review that the waiver should be renewed.

“Without any useful data from UP’s Test Waiver Committee to support the extension, we do not believe that the continued use of WTD technology is a safe and acceptable substitute for physical inspections by trained Carmen,” Regan said in the February letter.

Regan told FreightWaves that FRA rejected UP’s waiver extension requests in 2014, 2017 and 2021. 


FRA said its safety board denied UP’s petition in July 2021 because the railroad did not provide sufficient data and analysis fully demonstrating the claimed safety benefits. 

“We think that the focus of bringing new technology into a centuries old industry like railroading … [should be] on making railroads safer. It has to be a complement to what the workers do. It has to make it so that employees who are highly trained and highly skilled at what they do are given additional tools to do their jobs in the safest possible manner,” Regan said.

He continued, “We welcome these changes. We want to make our job safer. We want to make sure that the union that the workers have every tool at their disposal to do their jobs appropriately. But this is not the way to do that. Asking for waivers is not the way to do it properly and to make sure that it’s implemented in a responsible way.”

The debate over WTDs is similar to the one that unionized maintenance-of-way employees are having with the railroads over how the railroads should deploy track geometry technology, a component of automated track inspections. They contend that BNSF’s (NYSE: BRK.K) request to FRA to expand that technology’s deployment to two additional territories is an opportunity to reduce the number of visual inspections within those territories.

Union Pacific defends use of WTDs

But UP says WTD technology has caught defects that visual inspections have missed.

“The use of technology is an opportunity for Union Pacific to improve on its strong safety record. Our initial findings indicate that wheel temperature detectors identify more defects than traditional detection methods, which translates into a safer operation for both the public and our employees,” UP told FreightWaves.

“The use of this technology will not eliminate visual inspections by trained personnel. The wheel temperature detectors change the frequency of when a test is required, eliminating unnecessary brake tests and allowing our inspectors and train crews to focus attention on those brakes that warrant attention,” UP said.

The Association of American Railroads, which has lent its support to UP’s waiver requests, said it supports its members’ desire to pursue safety enhancing technologies such as WTDs.


WTDs identify cars with ineffective brakes at a higher rate than a manually performed intermediate brake test, AAR said. As a result, the technology expedites the repair or replacement of thousands of freight car brakes that might not have otherwise been immediately identified under existing FRA regulations. 

AAR also said that all cars identified by a wheel temperature detector had already passed a manually-performed FRA initial terminal brake test.

FRA is still reviewing UP’s waiver. But it has said that there is nothing to prevent a railroad from employing WTDs or “hot wheel detectors” to ensure brake health effectiveness. Such systems can accurately determine if brakes are working properly in real time, according to FRA.

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Joanna Marsh

Joanna is a Washington, DC-based writer covering the freight railroad industry. She has worked for Argus Media as a contributing reporter for Argus Rail Business and as a market reporter for Argus Coal Daily.