What is Dwell Time?
Dwell Time Definition
Dwell time, or contact time, is the time specified by a manufacturer that a disinfectant must be left on a surface to ensure disinfection. Successful disinfection will only occur if the proper dwell time is followed. Unless the manufacturer specifies, the spray and immediately wiping off the formula will not disinfect a surface. Most disinfectants require between 30 seconds to 3 minutes of dwell time to disinfect, although some require up to 10 minutes.
The proper dwell time varies by formula and appears on the disinfectant’s label and the manufacturer’s safety data sheet (SDS). Therefore, it is essential to clean surfaces before disinfecting. Otherwise, dirt and debris can shield pathogens, preventing the disinfectant from reaching them and rendering dwell time irrelevant.
To ensure proper dwell time, many custodial operations instruct their healthcare environmental services (EVS) and custodial technicians to spray a surface and move on to other surfaces or responsibilities, then return to wipe the disinfected surface after the proper dwell time.