With more than one-third of global greenhouse emissions related to buildings, the success of sustainability initiatives rests on the shoulders of a largely unsung population: the service workers who operate and maintain them. A young vocational training initiative, the Green Janitor Education Program, aims to increase maintenance and cleaning staff’s understanding of eco-friendly practices, with a particular focus on energy efficiency. The classes encourage greater ownership over janitors’ work and seeks to improve communications among service workers, their managers and building tenants.

Many programs exist to train engineers and architects in eco-friendly design and construction, but connecting to janitors about their role in maintaining sustainable practices throughout a building’s lifecycle has been far rarer.

“We saw that there was a need to really do an education piece about not just how to do the work but why these changes were happening and how the work they were doing every night connected to the bigger picture,” says Aida Barragan, executive director of Building Skills Partnership (BSP), a nonprofit that provides vocational training for low-wage service workers in the janitorial and maintenance trades. In addition to the Green Janitor Education Program, BSP runs classes in ESL, digital literacy and citizenship. (They also have initiatives to increase access to higher education among the children of janitors, who are primarily Latino immigrants.)

The need for the Green Janitor program, which was first piloted in eight buildings in 2014, has increased as more buildings seek LEED certification (developed by the USGBC) or adopt their own set of sustainability standards. As they do, Barragan says, workers’ daily or nightly routines began to change, incorporating more tasks related to energy efficiency, water conservation, green cleaning and waste diversion.

“Their equipment changed, supplies changed, the system in the building changed,” she says, which sometimes led to misconceptions. If buildings adopted thinner, compostable trash bags, workers sometimes thought they were just being given cheaper product. Others worried they weren’t providing the same quality of service when newly adopted green cleaning products didn’t smell like they expected. “Folks really feel a commitment to their work, and they’re proud of work they do, and sometimes they do interact with tenants, and want to feel like they’re providing a good quality cleaning,” says Barragan.

BSP developed the curriculum with the U.S. Green Building Council’s Los Angeles chapter (USGBC-LA), and partners with the Building Owners and Managers Association of Greater Los Angeles (BOMA) to connect with interested properties. Workers belong to the Service Employees International Union (SEIU), United Service Workers West chapter, and the labor union is a program partner.

Training in the Green Janitor program is conducted at janitors’ workplaces; they meet on paid time two hours a week for 15 weeks to complete the 30-hour curriculum. Workers take a mid-term and final exam, and graduate with a certification backed by the USGBC-LA. The program, like most of BSP’s work, is funded by a clause in the SEIU’s collective bargaining agreement, requiring employers of union workers to contribute to a vocational training fund. For the 2014 pilot, BOMA reached out to interested building owners, which resulted in 126 janitors being trained in eight buildings and a report that cited a demonstrable higher understanding of green concepts post-course. Today, over 300 janitors have been trained in L.A.

Janitors come to the program when their employers, building owners or realty companies request the training. One property owner, Kilroy Realty, implemented the program on several sites in L.A. and then expanded to its entire portfolio, which spans from Seattle to San Diego. Existing buildings looking to recertify under USGBC’s LEED for Existing Buildings: Operations and Maintenance program can receive a credit if workers undergo the program.

USGBC-LA executive director Dominique Hargreaves says that while the LEED standard for new construction offers a great opportunity to decrease the built environment’s impact, “the greatest opportunity for energy efficiency and real conservation … comes from improving what is already there.” Participants in the program learn about vampire energy being leached by plugged in but idle appliances, about the importance of properly sorting recyclable materials, about how the chemicals in traditional cleaning products could harm their health.

Because workers have different levels of education and comfort with the English language, classes are conducted primarily in Spanish with many interactive, demonstrative activities. Ana Velasquez, a certified green janitor at City National Plaza in L.A., said through a translator that she was particularly impacted by an activity in which the instructor held up a bag of “garbage,” and demonstrated how much of its contents could actually be reused or recycled. She was also struck by a walk-through of a single floor of an office building after the tenants had left, during which students checked off how many lights were left on, how many appliances plugged in, etc. Mentally multiplying the waste across all of the floors of the building, all of the buildings in the city, made her aware of the scope of the challenge. She also says she feels more ownership over the entire buildings’ operations, not just her assigned area.

Barragan says the program focuses on that holistic vision to make workers not only compliant but also proactive. Workers “have a really keen pulse on tenant activity,” says Hargreaves. “They know which computers are left on, which lights are left on.” BSP has recently adjusted their vocational ESL curriculum to review in English the same topics covered in the Green Janitor certification program in Spanish, to reinforce the lessons and make it easier for workers to communicate with managers and tenants about what they see and what changes they recommend.

Those changes are following workers home as well. Barragan says the impact on personal practices has been even greater than expected. One worker became so diligent about unplugging unused devices he was able to cut his family’s power bill in half. When an older son offered to help pay it, he retorted that saving money was a bonus, not the main motivation. Enough other workers were interested in composting that BSP ran an extra class on it. When asked if the program has impacted her practices at home, Velasquez replied, “Si, one hundred percent.”

Hargreaves says the interest of large companies like Kilroy are expanding the program’s reach beyond L.A. Workers have been trained in San Diego, Orange County and the Bay Area. USGBC-LA has been speaking to representatives of nonprofits who train service workers in other cities, including Chicago and New York. New York’s USGBC chapter has a similar program, GPRO, which trains electricians, plumbers, building superintendents and property mangers, so the two chapters are looking to meld the best of these complementary trainings.

“[Service workers] really are part of this cycle of sustainability,” says Barragan. She thinks the training is important “for their own motivation and really recognizing the value that they are providing in a building. I think it’s important that they themselves realize it but also everyone else recognizes it.”