Cleaning stinks — literally. In fact, janitorial staffs spend a good portion of each day dealing with unpleasant odors. The work may not be glamorous, but it is extremely important and requires a good deal of skill.

Foul odors can lurk behind any restroom door. It’s no wonder cleaning crews devote a lot of time to the fight.

“I’d say 30 percent of our cleaning efforts deal with odor control,” says William Friske, president of Friske Building Maintenance Co., Livonia, Mich. “If odors linger after we clean an area, then the assumption will be that we never serviced that area, no matter how clean it appears.”

There are four steps cleaning crews should follow when eliminating bad odors: find the odor’s source, clean, deodorize, and possibly seal the surface to lock in odor. Knowing these four steps can help with any odor issue.

“Inevitably, clients will ask questions about odor situations that are unique, which you’ve never encountered,” says Jeff Bishop, author of Comprehensive Deodorization. “By recalling these four basic procedures, you can actually sound intelligent while you brainstorm through the situation and arrive at a conclusion that seems logical.”

Step 1: Find the Source
Spraying something sweet in the air, then walking away is not effective odor management. Unfortunately, that’s exactly what many cleaning crews do.

“People don’t want to smell lemons or tulips, they want to smell nothing,” says Marty Shafer, director of Environmental and Guest Services for the University of Iowa in Iowa City.

Smell something fishy? Find the fish. Getting to the source of a bad odor is the key to eliminating it.

When a foul odor is detected, cleaning crews should do a thorough inspection to find the source, either using modern tools (black lights, for example) or the old sniffing method. Once the odor’s source is located, the crew must determine the cause and extent of the problem.

“If there is an odor, it’s because there is something wrong,” Shafer says. “We don’t like to mask odor. That is not my job. My job is to find out what is causing the odor and to get rid of it.”

Step 2: Scrub-A-Dub-Dub
Once the odor source is found, the only way to get rid of it is with a deep cleaning.

The area that causes most odor problems for cleaning crews is the restroom. One reason is that restrooms often have poor ventilation and smelly bacteria thrive in warm, damp climates. Cleaning crews must work with the building’s HVAC professionals to keep good airflow in the restroom.

Soiled surfaces in the restroom should be soaked for 10 minutes with a high-quality enzyme cleaner. Then the area should be cleaned with a disinfectant. To prevent odors, every surface should be cleaned daily with a disinfectant. Areas that often get overlooked include the sides and bottoms of stall partitions, walls and fixtures. Restroom floor mats can prevent urine from coming in contact with floors, but they too must be cleaned and replaced regularly.

The floors should also be mopped daily with a bacterial enzyme disinfectant, which will destroy organisms without ruining grout. Change the mop water often to prevent bacteria in the water. Leftover solution in the mop bucket can be poured down the floor drain to keep it odor-free.

Any area with odor problems should be cleaned in a similar manner. The most important part of the procedure is to thoroughly clean every inch that surrounds the affected area.

Step 3: Deodorize
The final step toward eliminating odors, in most cases, is to deodorize. This replaces the foul odor with a more pleasant scent. The area must be thoroughly cleaned first, otherwise the deodorizer will only temporarily mask remaining odors.

“There are some deodorizers out there that will mask odors for up to 30 days,” says Scott Rendall, owner of Rendall’s Sci-Clean in Brighton, Mich. “Once the deodorizer wears off, you’ll have the problem again. We hear horror stories about cleaners who go clean carpets and put out a deodorizing mask and say the problem is gone. Then 30 days later the smell is back because they haven’t dealt with the source of the problem.”

Deodorizers can be applied in a number of ways — by mopping them onto the floor or spraying them into the air, as time-released spray, and through blocks placed in toilets and urinals that apply enzymes and deodorizers with each flush.

Step 4: When All Else Fails
“At the end of the day, you’ll prevent most odors with regular cleaning and a good HVAC system,” says Shafer.

While this is typically true, there are some cases when odor removal is impractical, too expensive, or requires several treatments over an extended time period. In these rare and severe cases, the final step is to seal the odor into the surface.

For example, it may make most sense to paint over heavily smoked drywall with a sealer or to use shellac on the back of pet-stained carpet.

“Sealing surfaces not only improves their appearance, but it also speeds up the progress of overall deodorization,” says Bishop. “The heavier the residue or the more porous the surface, the more consideration of surface sealing is required. But cleaning always precedes the sealing process, if at all practical.”

A Job Well Done
To ensure successful odor control, Bishop suggests using the “overkill” method. Clean a larger area with more chemicals for a longer time than what you think is necessary, he says.

In the end, what matters most when dealing with odors is to go beyond superficial cleaning to get to the root of the problem.

“The thing we always remember is if we eliminate the source, we’ve eliminated the problem,” says Rendall. “A residual smell means there’s still a source there.”

Becky Mollenkamp is a Des Moines, Iowa-based freelance writer.