135 million euros — that is how much the Société Nationale des Chemins de fer Français spends each year to ensure the cleanliness of its trains and a pleasant journey for passengers. In addition to security and regularity, cleanliness is one of SNCF’s top priorities. To meet the quality challenges imposed by the more than 20 diverse regions, in 2006 SNCF launched a detailed cleanliness study in three pilot sites in the West and North of Paris and in Nantes.

SNCF employed Six Sigma, supervised by CSC consultants, to optimize its cleaning processes, so that each euro invested in the process provides returns for travelers. The approach focused on five major steps: defining the project, assessing the scope, analyzing results, implementing solutions, and monitoring performance.

“CSC consultants have spent enough time in the field to gain credibility with the employees. They can propose indicators and promote solutions at all levels of the company,” says Christian Proux, manager in charge of SNCF’s cleanliness projects.

Although the project met the necessary prerequisites to implement Six Sigma — measurable process, chronic defaults, tangible benefits, customer impact, no clearly identified solution — starting the project turned out to be difficult. The trains’ internal and external cleanup is a complex process, combining the operations’ continuity on permanently moving sets of train cars and the quality of services managed by an external provider.

Significant results in the external cleanup 

The Six Sigma project’s first benefit was to provide a culture of measurement. Before the project was started, SNCF had evaluated performance as an average. With the more precise measurements provided by Six Sigma, SNCF could identify at a given moment which set of cars had been cleaned within the deadlines, and which had not.

To be considered clean, the sets of cars must be cleaned up in a wash station every three days. While the previous indicators reported an average result of 3.2 days (“rather good”), the measurement performed during the project showed a strong disparity: Some sets of wagons were washed twice a day, while others were washed every eight days or longer. One case even reported 27 days between cleanings. The indicator measuring compliance with the three-days rule, integrated in the Six Sigma approach, revealed that the compliance rate was only 48 percent.

A detailed study of critical aspects, such as the lack of preventive maintenance for the wash stations and the inefficient programming of train washes, enabled CSC and SNCF to precisely target the required improvements and obtain everybody’s adherence to them. As a result, the indicator measuring compliance with the cleanup rules increased from 48 to 66 percent. A six-month forecast for one line's external cleanliness was 80 percent.

Reorganizing the interior cleanup process

The trains’ interior cleanliness is the result of a complex, day-and-night process that is almost invisible to passengers. Six Sigma’s approach helped measure and analyze all the elements of the process and define real performance indicators. While the analysis of cleanup operations revealed some failures on the part of contractors when performing their services, it also highlighted SNCF’s need to manage more rigorously.

For instance, Six Sigma identified cases where a high-speed train needed to be cleaned in 20 minutes while it was parked. To do so would require a crew of 20 people, yet the contractor generally employs teams of five. It could not be expected to hire 15 people for 20 minutes of work. The Six Sigma project identified such malfunctions and also identified the associated processes — materials’ parking time and contractor’s workload — to create innovative solutions.

Six Sigma’s approach, which aims to analyze an issue in an exhaustive and rigorous way, has proven helpful for managing the cleaning process. Improvements have already been noticed, leading SNCF to consider a progressive deployment of the methodology throughout the entire network.

“CSC has generated interest in Six Sigma’s approach,” notes Olivier Noirot-Cosson, SNCF project director. “I had the chance to be trained by a Six Sigma Black Belt during the project, who helped us understand an extremely complex subject and identify clear objectives to obtain tangible results.”