PERSONAL PROTECTIVE EQUIPMENT FOR VIRUS HANDLING: EVALUATION AND IMPROVEMENT OF ENSEMBLE DESIGN TO REDUCE THERMAL DISCOMFORT AND PHYSIOLOGICAL RESPONSES

• Main Author: Totong
• Format: Dissertations
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/84358
• Institution: Institut Teknologi Bandung

Diseases caused by acute viral infections have occurred repeatedly, so anticipatory steps must be prepared. During the pandemic, health workers must wear personal protective equipment (PPE) to reduce the risk of infection. However, it causes side effects in the form of thermal discomfort and the emergence of excessive physiological responses. Using PPE in hot work environments can cause heat stress, resulting in cognitive impairment, fatigue, increased workload, decreased productivity, and work accidents. Several studies have investigated the negative impact of PPE use; however, they need to provide adequate information on the level of heat stress in PPE use in Indonesia. Administrative and engineering interventions can ameliorate discomfort but cannot be done in emergency conditions or health worker shortages. Some studies have improved PPE discomfort by improving the PPE ensemble design. However, there is still a need to integrate the PPE ensemble design, cooling devices, and cooling wear suitable for tropical areas. This study aims to evaluate and improve the ensemble design of PPE for virus handling to reduce the thermal discomfort and physiological response of its users. The research was conducted in two stages: Phase I identified problems by evaluating the use of PPE in tropical environments and its impact on thermal discomfort and physiological responses. Phase II intervened to reduce the negative impact of PPE use by improving PPE ensemble design. The resulting PPE ensemble is expected to meet technical requirements and be comfortable to wear to support health workers' performance. The study was conducted using a laboratory experimental approach. Phase I research began with testing PPE textile materials' technical and thermal comfort characteristics. The PPE ensemble with the best characteristics was used for the experiment. Twelve participants were involved in the experiment. Participants performed 3 acclimatization steps and physical efforts that represented the activities of health workers at work. Experiments were conducted in 3 working environment conditions: temperature (20 ± 2) oC, temperature (25 ± 2) oC, and temperature (30 ± 2) oC with relative humidity (50 ± 10)%. Parameters measured included microclimate conditions (temperature and humidity), thermal discomfort vi (thermal sensation and wetness sensation), and physiological responses (body core temperature, skin temperature, heart rate, oxygen consumption, blood pressure, and sweat intensity). One-way ANOVA (p = 0.05) was used to analyze the effect of environmental conditions on the tested parameters. The results of phase I research are data on textile material characteristics, thermal discomfort, and physiological responses that serve as the basis for improved PPE ensemble design. The results of Phase I experiments show that there is a significant effect of working environment temperature (20 oC, 25 oC, and 30 oC) on microclimate temperature and humidity, thermal and wet discomfort sensations, core body temperature, skin temperature, heart rate, systolic blood pressure, and sweat intensity. There was an upward trend in thermal discomfort levels and physiological responses from the working environment temperature of 20 oC to 30 oC. At 30 oC, the microclimate temperature approached 34 oC, the relative humidity reached 100%, the thermal discomfort sensation of heat and wetness reached -3 (very uncomfortable), the core body temperature reached more than 38 °C, and the highest heart rate reached 132 bpm. The problem was that body heat and sweat accumulated in the microclimate between the body and clothing because it was retained by PPE that covered almost the entire body and was made from impermeable textile materials. The problem that occurs in the use of PPE is the high microclimate conditions between the body and clothing (temperature and humidity) caused by body heat and sweat vapor that cannot be transferred to the environment. Hence, intervention is needed in Phase II research. The first intervention improved the PPE ensemble consisting of a medical uniform and medical coverall that facilitates urination and can be used several times. The next intervention was to make devices to reduce the temperature and humidity of the microclimate. The first device is cooling wear consisting of a vest made of mesh fabric equipped with phase change material (PCM) at 23 oC. The next device is a cooling device that can flow clean, conditioned air 23-27 oC into the microclimate between the body and clothing and carry heat and sweat vapor to the environment. The test results of the PPE ensemble prototype at an ambient temperature of 30 oC and 50% RH showed a significant effect of the addition of cooling wear and cooling devices on thermal comfort and physiological responses. The addition of cooling wear can significantly reduce microclimate temperature, sweat intensity and improve the sensation of heat and wetness discomfort but does not affect to microclimate humidity, skin temperature, core body temperature, heart rate, systolic blood pressure, diastolic blood pressure, and oxygen consumption. The addition of cooling devices can significantly reduce microclimate temperature and humidity, skin temperature, body core temperature, heart rate, systolic blood pressure, and sweat intensity and improve the sensation of heat and wet discomfort but does not affect diastolic blood pressure and oxygen consumption. Based on the above analysis, cooling devices have a better effect on the comfort of using a PPE ensemble than cooling wear. The implications of this study in managing viral diseases consist of the availability of data on the level of thermal discomfort and physiological response profiles that vii can be utilized by parties concerned with handling viral diseases. Second, the availability of a comfortable PPE Ensemble in a tropical environment can be mass- produced and used by health workers so that they avoid the risk of heat stress, work more productively, and avoid mistakes. Some further research includes aspects of production feasibility studies, conformity testing with certain requirements, and formal licensing. The results of this study can also be used as a reference in decision-making for stakeholders such as the Ministry of Health, hospitals, and PPE manufacturers who handle dangerous viruses.