Team approach to Ergo Dolly cuts injuries and saves money
Pre-intervention state of safety
Return on Investment
International Truck and Engine Corporation’s Springfield Assembly Plant experienced a high rate of injuries in the cab trim department. Prior to this project, the workers were reluctant to get involved because of the union-management relationship. Analysis of the injury data indicated employees entering and exiting the cab were slipping, tripping and falling due to the high step-in. A cross-functional team was formed to address the reduction of injuries. The Ergo Dolly was developed over several iterations with the input of many workers. The new design incorporated a step that made entry and exit easier. The Ergo Dolly has completely eliminated trips and falls in its first full year of implementation, contributing to a reduction in the departmental injury rate. In addition, the Ergo Dolly contributed to better ergonomic positioning of other work on the truck cab and increased productivity.
The intervention project would take place in Cab Trim (Department 65), a large and complex sub-assembly area at the Springfield Assembly Plant. Cab Trim dresses (trims) the inside of the cab; installs glass, grab handles and marker lights; and performs work on the external firewall. These operations are performed on a 500-foot straight-line stretch of conveyor track. Plant engineers were installing a new conveyor system in Department 65, which provided a unique opportunity for the project team.
There were 235 operators in the department at the onset of the project. Few had ever been involved in design reviews or had the opportunity to participate in a spirit of cooperation. The project team sought to eliminate these barriers and to engage union buy-in by leveling the playing field, treating all team members with the same respect, earnestly soliciting input and incorporating their ideas.
Pre-intervention state of safety
Before the creation of the “Ergo Dolly” the department had a history of operator injuries while getting in and out of the cab on the moving line. In 1998, the Ergonomic-Health and Safety organization used ergonomic analysis tools to evaluate departmental safety. They identified the dolly as the number one cause of injury in the Cab Trim Department based upon 13 injuries with a projected $123,550 payout in the calendar year.
In 1999, a cross-functional team from UAW safety, UAW Ergonomics, Industrial Engineering, Manufacturing Engineering, Production, Plant Engineering, the Process Evaluation Center (PEC) in Sidney, OH and Springfield management came together with the goal of eliminating dolly-associated injuries. The vision was to create a working environment in Cab Trim that was unparalleled for safety, quality, productivity, and operator satisfaction.
Initially, some line workers were reluctant to get involved in the process and said, “You’re the engineers. I don’t want to be held responsible if it doesn’t work. Why should I make suggestions? No one will listen, anyway.” These arguments disappeared when the first prototypes incorporated many of the UAW line assembler’s suggestions.
The team recognized that no matter who designed the new dolly and no matter who got credit or blame, the operators would end up living with the result on a daily basis.
The injury documentation contained very little historical information useful to problem solving. However, the database did contain one useful field — a one-sentence description of the incident that described how the injury occurred. This data was used in 1999 to identify key causes of injuries in the Cab Trim Department. In that same year, a baseline-screening tool was used for ergonomic task analysis. This analysis identified body parts affected and rated the risk levels that we converted to priority ranking.
Among the initiatives that were going on in early 1999 was a defined effort on behalf of the corporation to “change the culture” and to adopt corporate behaviors that were more interactive and much less confrontational.
The old school of thought also had people calling for the safety representative to communicate any issues. This would then be communicated up through their chain of command only to come down the management side. This led to an expansion of time and resources spent to address any needed issues.
Today’s environment has improved more to the point of direct communication with represented and supervision jointly addressing an issue before drawing on the “chain of command.” The trust and involvement factor has improved dramatically. Many barriers have been eroded or torn down.
The right way to build the dollies became an item of discussion during the many team meetings. We developed a preliminary list of features required for a dolly.
The first prototype was built for trial off line. A team of assembly workers, group leaders, and foreman, industrial engineering, manufacturing engineering, plant engineering, worker and management representatives for safety and ergo reviewed the prototype, identified what did and didn’t work and suggested changes. After discussion, argument, negotiation — and sometimes a little yelling — we came to a consensus on the requirements for the next iteration of design.
The new requests on dolly design from an implementation standpoint were quite difficult given our timeline and budget. There were significant issues from a plant engineering perspective. By the time the ergonomic changes were requested, plant engineering had already begun designing the conveyor system for the smaller prototype dolly. This was a problem because now the team and the conveyor manufacturer were going down two different paths. The dolly had to be put on hold and some key conveyor questions could not be answered until the new dolly changes had been proven through trial build events and team consensus.
In late February 2000 we spent an additional $3,000 to build a prototype pullout step and raise the cab on the dolly to a recommended height of 23 inches (from manufacturing floor to bottom of cab). The dolly modification was complete and delivered to Process Evaluation Center in early March for a trial build event. Input from this build event recommended further changes.
The following responses regarding the addition of the step were recorded at the Ergo Dolly prototype design review with feedback from Local 402 at the Process Evaluation Center. Each day different operators participated in the review. More than 55 operators took part in the nine-day review.
The second prototype incorporated these changes and was built by the conveyor contractor. This was used for the next build event. From this build event the dolly design was slightly modified in regard to step placement and weight.
This complete process of evaluation did not allow the dolly to be approved for mass production until the beginning of June 2000. The approval process consisted of a signed buy-off from production, ergonomics, safety and plant engineering.
The average cost to build 85 standard dollies with no step was $85,000. To build the additional steps for all 85 dollies cost an additional $917 each, or $77,945.
Return on Investment
The team spent $77,945 to achieve a reduction in injury related costs of $123,550. This yields a payback of less than eight months for safety effects only. Because job rotation is frequent in the department, a random cross-section of the departmental operators was invited to participate in the design reviews.
After the project team clarified their intentions, everyone invited accepted. This propelled a synergistic dynamic that had been lacking in previous programs and provided levels of anticipation and excitement for the outcome.
Our assembly lines are punctuated by variety, not commonality, because each customer has specific needs and buys a truck customized to fit its application.
The Ergo Dolly design needed to be adaptable to cover a wide variety of options and configurations. It is compatible for use by operators of every shape and size. The increased height of the cab on the dolly reduced the number and severity of bending by employees working on the unit.
Operations that would have been performed at knee level are now at workbench height. Most operations are in a better location for visual inspection, making it easier for the assembler to perform quality work, as well as making it easier for the inspectors to spot defects.
The full case study, and others like it, are available in “Case Studies in Safety & Productivity Volume II” produced by the Research & Statistical Services Group of the National Safety Council, Itasca, IL. For information go to the Products section of the Council Website, www.nsc.org .
This case study by International Truck and Engine Corporation – Springfield Operations, was awarded First Place in the National Safety Council’s 2002 Awards for Outstanding Achievements in Safety & Productivity. The case study was written by their Ergo Team and submitted by Michael R. Smith, New Program Launch Manager, e-mail address:firstname.lastname@example.org