Engineering Control Readiness and Airborne Fungal Contamination in Forensic Pathology Facilities in Gauteng, South Africa: A Cross-Sectional Occupational Hygiene Study

Airborne fungal contamination poses an occupational health risk in environments where engineering-controls are essential for maintaining indoor air quality. However, evidence integrating assessments of engineering-control readiness and airborne fungal contamination in forensic pathology facilities remains limited, particularly in low- and middle-income countries. This study assessed engineering-control readiness, indoor environmental conditions, and airborne fungal contamination in three public forensic pathology facilities in Gauteng Province, South Africa, and explored factors associated with airborne fungal contamination. A cross-sectional occupational hygiene study was conducted in three public forensic pathology facilities. Engineering-control readiness was assessed using structured walkthroughs and summarised using a study-specific Engineering Control Readiness Index (ECRI). Indoor temperature, relative humidity, carbon dioxide (CO2), and airborne fungal concentrations were measured concurrently. Duplicate fungal air samples were collected at predefined locations over three consecutive sampling days. For the primary regression analysis, duplicate fungal measurements were averaged within each physical sampling location and sampling day, yielding 54 indoor location-day observations from 18 physical indoor sampling locations. Multivariable log-linear regression included facility, functional work area, area-specific ventilation and environmental-control deficiency, temperature, relative humidity and CO2, with cluster-robust inference accounting for repeated measurements within physical sampling locations. Overall ECRI scores ranged from 50.1% to 53.9%, with ventilation and environmental control representing the weakest domain. Airborne fungal concentrations differed significantly between facilities, with FPF G recording the highest indoor median concentration (740 CFU/m3). Cladosporium spp. and Penicillium spp. predominated. After adjustment for facility, functional work area and environmental conditions and accounting for repeated sampling, engineering-control deficiency was not independently associated with fungal concentration (adjusted change per 10-percentage-point increase: −16.3%; 95% CI: −70.9% to 140.9%; p = 0.727). Substantial engineering-control deficiencies and airborne fungal contamination were identified; however, the independent contribution of engineering-control deficiency could not be estimated with adequate precision in this three-facility study. Larger longitudinal studies incorporating objective ventilation-performance measurements are required to clarify the contribution of specific engineering controls to occupational bioaerosol exposure.