Biofilm Control Inside Secondary Water Storage Containers Using UV LIght

Abstract

This thesis investigates the feasibility of ultraviolet (UV) light treatment for biofilm control inside secondary storage containers used in humanitarian settings. A scoping literature review investigating real‑world UV light treatment application revealed that, even though it is effective beyond controlled laboratory settings, it is underexplored as a method for biofilm control in humanitarian contexts. To address this gap, a ray tracing model was developed to simulate UV irradiance distribution within a representative jerry can, and experimental validation showed model predictions were within 17% of measured values. Lab-grown biofilms were then treated at locations inside the jerry can receiving moderate and low levels of UV irradiance. At a maximum UV dose of 16 mJ/cm², the location receiving moderate UV irradiance achieved 2.47 ± 0.75 (average ± standard deviation) log-reduction value (LRV) while the location receiving low UV irradiance achieved 2.99 ± 0.07 LRV. Comparisons with other UV/biofilm research showed that similar germicidal thresholds could be achieved even with the lower parameters incorporated into this research. These findings demonstrate that UV light treatment is a technically viable method for biofilm control inside secondary storage containers used in humanitarian settings. Future research investigating this treatment method under real world conditions will prove to be the next key step in determining its feasibility for future implementation in humanitarian contexts.