New Study Reveals Limitations of Disinfectant Performance

July 14, 2017

Sealed Air’s (NYSE: SEE) Diversey Care division today released the first of a series of studies conducted with Purdue University, which focus on the bactericidal efficacy of disinfectants. The research, expected to be published in the August 2017 issue of the American Journal of Infection Control (AJIC), determined that the three tested disinfectants were significantly less bactericidal at lower than label use contact times and concentrations.

“In busy healthcare facilities, disinfectants are often applied once and left to dry, regardless of the unique label instructions. As this study shows, disinfectants don’t live up to their claims if they get over diluted or are not reapplied as directed,” said Peter Teska, Infection Prevention Application Expert, Diversey Care. “Choosing an Environmental Protection Agency-registered disinfectant and following label directions are key elements of effective disinfection and preventing the spread of healthcare-associated infections.”

Accelerated hydrogen peroxide (AHP), quaternary ammonium compounds (Quats) and sodium hypochlorite were each tested on stainless steel surfaces at room temperature (77 degrees Fahrenheit) using EPA procedure MB-25-02. For each treatment, bacterial reduction was calculated, compared and analyzed to find the following key results:

  • All disinfectants were significantly less bactericidal against S aureus when applied for times shorter than label contact times.

A one-minute contact time with AHP resulted in a 56.8 percent reduction compared with 100 percent at the recommended five-minute contact time. At contact times of one, two, three and four minutes, Quats resulted in 15.7 percent, 47.4 percent, 62.5 percent and 70.0 percent reduction compared with 100 percent at the 10-minute label contact time. Sodium hypochlorite applied for one minute resulted in a 76.3 percent reduction compared with 100 percent at the five-minute label contact time.

  • All disinfectants were significantly less bactericidal against S aureus at lower than label concentrations.

AHP at 25 percent and 50 percent label concentrations resulted in 40.9 percent and 75.7 percent reductions. Quats at 25 percent and 50 percent label concentrations resulted in 62.5 percent and 67.5 percent reductions and Sodium hypochlorite at 25 percent label concentration resulted in 50.7 percent reduction.

  • The bactericidal efficacy of the sodium hypochlorite disinfectant was most tolerant to decreases in concentration and contact time. AHP followed close behind while the Quat disinfectant was the least tolerant and most affected by contact time and concentration.

“Understanding the antimicrobial efficacy of disinfectants under different conditions offers healthcare facilities valuable information on disinfection limits, opportunities and corrective actions,” said Haley F. Oliver, Associate Professor, Department of Food Science, Purdue University.

For more information about infection prevention products from Diversey Care, visit



See the latest posts on our homepage


Topic Area: Press Release

Recent Posts
Recent Posts

Cooling failures at fertility clinics may have damaged hundreds of eggs

San Francisco fertility clinic experienced a liquid nitrogen failure in a storage tank holding thousands of frozen eggs and embryos


Focus: Security

A guide to healthcare background checks

More than one-third of the acute care hospital beds are in older buildings that will not be able to contain those beds unless they are upgraded by that date


UK hospital fire safety walls won't be fixed until late 2019

The breaches in walls at the Coventry hospital were discovered in 2016


Dental clinic accused of using contaminated water during procedures

Suit says office failed to actively monitor the water quality or disinfect water lines


Focus: Fire-Life Safety / Column

Regulations, Codes & Standards Q&A: Fire pins

Brad Keyes discusses regulations for aluminum astragals


Post Comment


• News and Updates
• Webcast Alerts
• Building Technologies

All fields are required.