The design of hospital handbasins may contribute more to the spread of drug-resistant bacteria than previously recognized, according to a recent global review of design standards. A team at Flinders University examined how poorly designed sinks in healthcare settings could intensify outbreaks of superbugs such as Carbapenemase-producing Enterobacterales (CPE), which pose significant treatment challenges.
The findings were published in the Journal of Hospital Infection and compared handbasin design guidelines from 39 countries with existing scientific evidence. The analysis revealed that current standards often lack uniformity and fail to address how specific design features influence microbial transmission. Mikaela Todarello, the lead author and a PhD candidate in Environmental Health, stated that while handwashing remains essential, poorly designed basins can undermine infection control measures.
The review identified several critical design flaws:
- Flat basin surfaces that allow water to pool, increasing splashing and microbial growth.
- Shallow basins that disperse airborne droplets, known as bioaerosols, beyond the sink area.
- Drains positioned directly beneath taps, which generate droplets when water hits the drain at high pressure.
- Inadequate water flow and basin slope, which affect splash behavior and contamination risk.
Todarello noted that while individual design elements have been studied, there is limited research on how they function together in real-world healthcare environments. “There is still limited research examining how these features work together during everyday use, or which combinations best reduce infection risk,” she said. The study suggests that even minor adjustments, such as relocating drains or modifying basin depth, could help reduce pathogen spread.
Improved engineering approaches could address these issues by minimizing splashing, reducing biofilm accumulation, and preventing contamination from reaching vulnerable patients. Harriet Whiley, a Flinders University environmental health expert, argued that handbasins should be integrated into infection prevention strategies rather than treated solely as convenience features. “We ask healthcare workers to wash their hands to protect patients. We should make sure the handbasins they use are designed with the same goal in mind,” she said. “Better engineering could reduce splashing, limit biofilm buildup and prevent contamination from spreading. We can do better, particularly in areas caring for patients who are most vulnerable to infection.”
Despite these opportunities, current guidelines show significant variation. Some countries emphasize splash reduction, while others prioritize material durability or ease of cleaning. Without standardized testing in real hospital environments, the most effective designs remain uncertain. Todarello stressed the need for further research, particularly in high-risk areas such as intensive care units, to address these gaps.