Field investigation of the heat stress in outdoor of healthcare workers wearing personal protective equipment in South China.

Since the advent of coronavirus disease 2019 (COVID-19), healthcare workers (HCWs) wearing personal protective equipment (PPE) has become a common phenomenon. COVID-19 outbreaks overlap with heat waves, and healthcare workers must unfortunately wear PPE during hot weather and experience excessive heat stress. Healthcare workers are at risk of developing heat-related health problems during hot periods in South China. The investigation of thermal response to heat stress among HCWs when they do not wear PPE and when they finish work wearing PPE, and the impact of PPE use on HCWs' physical health were conducted. The field survey were conducted in Guangzhou, including 11 districts. In this survey, HCWs were invited to answer a questionnaire about their heat perception in the thermal environment around them. Most HCWs experienced discomfort in their back, head, face, etc., and nearly 80% of HCWs experienced "profuse sweating." Up to 96.81% of HCWs felt "hot" or "very hot." The air temperature had a significant impact on thermal comfort. Healthcare workers' whole thermal sensation and local thermal sensation were increased significantly by wearing PPE and their thermal sensation vote (TSV) tended towards "very hot." The adaptive ability of the healthcare workers would decreased while wearing PPE. In addition, the accept range of the air temperature (T a) were determined in this investigation. Graphical Abstract.

Thermal discomfort caused by personal protective equipment in healthcare workers during the delta COVID-19 pandemic in Guangzhou, China: A case study

Background In contrast to the previous COVID-19 pandemic, most frontline healthcare workers (HCWs) worked on residents’ nucleic acid tests in outdoor environments, instead of taking care of COVID-19 patients in hospitals during the hot summer of 2021. Therefore, it is necessary to investigate the prevalence and characteristics of thermal discomfort caused by personal protective equipment (PPE). Methods A cross-sectional survey was conducted online at hospitals from 11 administrative regions of Guangzhou for the assessment of thermal discomfort among HCWs from June 12–16, 2021. Univariate and logistic regression analyses were used to explore the risk factors associated with thermal discomfort. Results A total of 3658 valid responses were collected. The thermal discomfort and humid discomfort levels increased from 2.91 ± 1.19 to 3.61 ± 0.72 and from 0.98 ± 1.36 to 3.06 ± 1.1 after wearing PPE, respectively (p < 0.01). Feelings of being “very hot” and “uncomfortably humid” were the most influenced by wearing PPE, increasing from 31% to 69.1% and from 9.1% to 45.7%, respectively. There were significant increases in the thermal discomfort level (3.75 ± 0.57 vs. 3.33 ± 0.89, p < 0.01) and the humid discomfort level (3.33 ± 0.95 vs. 2.54 ± 1.19, p < 0.01) between the comfortable group and uncomfortable group, accompanied by similar patterns in the feelings of being “very hot” and “uncomfortably humid.” For general thermal-related symptoms, the most common new-onset symptom was profuse sweating (80%) followed by labored breathing (55.2%) and excessive dehydration (46.8%), while facial swelling (74%) was associated with local thermal-related symptoms, followed by hand maceration erosion (56.7%) and visual impairment (49.3%). In the multivariate analysis, the apparent temperature of the environment (≥35 °C), working in negative-pressure ambulances and outdoors, continuing to wear PPE for 1–3 days during this period, being aged >40 years, and previous experiences fighting the pandemic were independently associated with thermal discomfort (p < 0.01). Immediately after PPE removal, 32.3% of respondents considered drinking ice water/another drink, followed by 25% shortening the duration of wearing PPE and 19.1% going to the toilet. A large proportion of the participants looked forward to modifications to the material of the suit (72.9%) and mask (53.4%) for heat dissipation and dehumidification, as well as anti-fogging goggles (60.2%), adding hydration equipment to PPE (53.4%), and using soft materials to reduce pressure (40%). Conclusions Thermal discomfort is common and degrades health physiology related to PPE in summer environments. This suggests that modifications to the current working practices are urgently required to improve the resilience of HCWs and enhance their services during pandemics.