Formaldehyde is a widely used chemical in pathology laboratories and a known occupational hazard with established carcinogenic potential. This study presents the design and validation of a low‐cost, Internet of Things (IoT)‐based monitoring system for real‐time formaldehyde detection in indoor clinical environments. The device integrates a ZE08‐CH2O electrochemical gas sensor, an ESP32‐WROOM‐32 microcontroller, and an LCD interface, all supported by embedded firmware for continuous environmental sampling. Field testing was conducted at a national pediatric pathology laboratory, where four critical work zones, grossing station, sample reception, tissue processor, and reagent storage, were monitored over a fixed time interval. Results from the custom‐built system were compared with a certified commercial monitor (Yvelines HTO 131) using Bland–Altman analysis to assess agreement. Mean differences across zones were within ±0.03 mg/m 3 , with 95% limits of agreement (LoA) ranging from −0.05 to +0.06 mg/m 3 and standard deviations of the differences ranging from 0.36% to 2.08%, supporting the system’s suitability for real‐time monitoring while also enabling the identification of concentration levels approaching occupational exposure thresholds, highlighting its relevance for occupational exposure monitoring in clinical settings. The total system cost remained below 60 USD, enabling scalable deployment in settings with limited technical infrastructure. The results support the clinical applicability of embedded formaldehyde‐sensing technologies as accessible tools for occupational safety in low‐resource healthcare environments.
Castillo et al. (Thu,) studied this question.