# How to get cheap clean air? Implementation of an affordable high-efficient air filtration ventilation system for operating theatres in a low-resource setting

## TL;DR

A low-cost, high-efficiency air filtration system was developed and tested in a hospital in Cameroon to improve air quality in operating theatres.

## Contribution

The study introduces a locally constructed, affordable air filtration system suitable for low-resource settings.

## Key findings

- The system reduced airborne particles by over 97%.
- Microbial contamination was reduced by 72%.
- The device functioned properly for 4 years without maintenance.

## Abstract

Clean air in the operating theatre (OT) is crucial for safe surgery in order to prevent surgical site infections. Air filtration devices are standard in most OT as required by international guidelines and regulations. However, in low-resource settings, common air filtration devices are only scarcely found in OT, mainly due to high cost. Context-adapted low-cost solutions for clean air in OT are urgently needed but not available. The aim of this study was to assess the effectiveness of a new mechanical air filtration system for OTs, to describe its technical details and compare its performance with DIN/ISO standards and natural window ventilation, at a district hospital in Mbouo, Cameroon.

An affordable (3,500 €) high-efficient air filtration system was developed, locally constructed and implemented. An evaluation was done after 4 years of regular use, comparing the system with ISO/DIN guidelines.

The device was still working properly after 4 years of regular use without any maintenance. The air filtration system reduced particles in the OT by >97%. The microbial contamination in the OT air was reduced by 72% after starting the device. Although it is not fully compliant with all DIN/ISO requirements, the ventilation system greatly improved the cleanliness of the OT air compared to ‘natural’ window-based ventilation.

This pilot study showed the feasibility and quality of a new context-adapted affordable air filtration device for OT in low-resource settings. Further studies and upscaling are needed. Construction plans are freely available.