The available chlorine concentration in commercial and household chlorine disinfectants

Abstract

　The current study measured the available chlorine concentration in commercial and household chlorine bleaches (referred to here as "disinfectants") in the liquid and spray forms. The available chlorine concentration in commercial liquid disinfectants is regarded as 5%. However, the results indicated that the available chlorine concentration in commercial liquid disinfectants was 4.39-6.53%, thus the available chlorine concentration was lower than 5%. Household liquid disinfectants were purchased at different times. Liquid bleach that was purchased 1 month prior had an available chlorine concentration of 5% or higher, while liquid bleach that was purchased 6 months prior had an available chlorine concentration of less than 5%. Liquid bleach that was purchased more than 6 months prior had an available chlorine concentration of less than 5%. As time passed after the liquid bleach was purchased, the lower its available chlorine concentration. Commercial spray bleach had an available chlorine concentration of 2.02-3.08%.

　Based on these findings, liquid disinfectant for norovirus disinfection must be used within 1 month of purchase, and it must be kept in a cool place. The results also suggested that a spray disinfectant diluted to the same concentration as a liquid disinfectant is not appropriate for norovirus disinfection.