Located at 8420 West Bryn Mawr Avenue in Chicago, U.S. Cellular Plaza is a Class A building that comprises three buildings totaling 637,000 square feet. Managed by Colliers, a global commercial real estate services firm, the ENERGY STAR rated property features numerous amenities, including a conference facility, fitness center, delicatessen and 24-hour security service. 

While many tenants transitioned their employees to remote work during the COVID-19 pandemic, leading to lower foot traffic at U.S. Cellular Plaza, Colliers understood that the property needed to maintain the highest levels of health and safety for occupants and visitors. 

The firm placed hand sanitizing stations in common areas, restricted elevator capacity to four people and required mask wearing in shared spaces like hallways and lobbies. It also sought a way to enhance the standard of cleanliness across the buildings. 

“First impressions are important. We want tenants and visitors to see a visibly clean environment,” said Kelly Conkle, Assistant Property Manager, Colliers. “The pandemic expedited our search for better cleaning with better machinery.”


Colliers turned to GSF USA, a leading provider of commercial cleaning services that implements its sustainability-focused Écologique cleaning program in commercial offices and schools. In addition to focusing on documented training and leadership development, the program prioritizes the use of safer chemicals and high-tech equipment. 

“The pandemic has caused many companies to look at cleaning differently,” said Kurt Kuempel, Vice President, GSF USA. 

GSF educated Colliers about the electrochemically-activated solutions (ECAS) it uses to clean and disinfect its customers’ buildings. The solutions from PathoSans are created with an on-site generator using salt, water and electricity. They are non-irritating and don’t contain added fragrances or volatile organic compounds (VOCs) that negatively impact indoor air quality (IAQ).

GSF also implemented new equipment, including e-mist sprayers to quickly and easily disinfect, HEPA-filter vacuums and a T350 Stand-on Floor Scrubber from Tennant equipped with the ec-H2O NanoClean® system, which electrically converts water into an innovative, detergent-free, solution.


With the help of GSF USA, Colliers and U.S. Cellular Plaza realize the following benefits:

Safer cleaning. Conkle says: “Many tenants’ employees are sensitive to harsh chemicals. We do not want anyone to have a reaction or be uncomfortable because of a harsh cleaner being used throughout our complex.” Using ECAS instead of harsh chemicals to clean and disinfect means that GSF’s employees and building occupants are not being exposed to any harmful or irritating chemicals. 

Enhanced floor care. The cleanliness of floors can influence first impressions upon entering a facility. GSF’s day porters and evening crew regularly use vacuums to maintain the appearance of carpet and hard flooring throughout the buildings. Additionally, the team utilizes a Tennant floor scrubber to increase productivity while thoroughly removing soils. According to Conkle: “The floorcare machines have been helpful. We believe the addition of better equipment will help to improve the cleaning quality.” 

“We are proud to oversee a sustainable cleaning program at U.S. Cellular Plaza,” added Kuempel. “We look forward to supporting Colliers as an increasing number of tenants bring their employees back to the office.”