chapter  6
25 Pages

Effectiveness of UV-C light irradiation on disinfection of an eSOS™ Smart Toilet

ByFiona Zakaria

96Ultraviolet germicidal (short wavelength UV-C) light was studied as surface disinfectant in an eSOS™ (Emergency Sanitation Operation System) smart toilet to aid to the work of manual cleaning. The UV-C light was installed and regulated as a self-cleaning feature of the toilet, which automatically irradiate after each toilet use. Two experimental phases were conducted i.e. preparatory phase consists of tests under laboratory conditions and field testing phase. The laboratory UV test indicated that irradiation for 10 minutes with medium-low intensity of 0.15 – 0.4 W/m2 could achieve 6.5 log-removal of Escherichia coli. Field testing of the toilet under real usage found that UV-C irradiation was capable to inactivate total coliform at toilet surfaces within 167 cm distance from the UV-C lamp (UV-C dose between 1.88 and 2.74 mW). UV-C irradiation is most effective with the support of effective manual cleaning. Application of UV-C for surface disinfection in emergency toilets could potentially reduce public health risks.