DEVELOPMENT OF RECOMMENDATIONS FOR DESIGNING PROTECTIVE CLOTHING RESISTANT TO THERMAL EFFECTS AND WEAR

УДК 677.02

ABSTRACT

This article develops recommendations for designing heat-resistant and wear-resistant personal protective equipment for emergency personnel, including firefighters, operating in high-temperature conditions, using local raw materials. The article examines the types of personal protective equipment and the classification of firefighters' special clothing. The working conditions of firefighters, their work processes, and the types of ergonomic actions they perform during firefighting were studied, and diagrams were developed. The wear topography of the specialized clothing used in practice has been studied.

As a result of the research, it was established that the areas most susceptible to friction under external influence are the back of the sleeve, the elbow area, the front and back of the coat, the front of the trousers, the knee area, and the back of the trousers. Thus, it is recommended to apply reinforced special fire-resistant coatings to the easily worn areas of the special clothing.

The results of the analysis show that in order to design special clothing for firefighters with functional properties, resistance to mechanical impacts, and high protection, the task was set to study their movement postures when performing various work operations. When performing various labor operations, firefighters were studied based on: the type of action; the technological process; and the method of performing the action.

АННОТАЦИЯ

В данной статье разрабатываются рекомендации по проектированию жаростойких и износостойких средств индивидуальной защиты для персонала экстренных служб, включая пожарных, работающих в условиях высокой температуры, с использованием местного сырья. В статье рассматриваются виды средств индивидуальной защиты и классификация специальной одежды пожарных. Были изучены условия труда пожарных, их рабочие процессы и виды эргономических действий, которые они выполняют при тушении пожара, и разработаны схемы. Изучена топография износа специальной одежды, используемой на практике.

В результате исследований было установлено, что наиболее чувствительными к трению под внешним воздействием являются область спинки рукава, область локтей, передняя и задняя части пальто, передняя часть брюк, область коленей и задняя часть брюк. Таким образом, рекомендуется наносить армированные специальные огнестойкие покрытия на легко изнашиваемые участки спецодежды.

Результаты анализа показывают, что с целью проектирования специальной одежды для пожарных, обладающей функциональными свойствами, устойчивостью к механическим воздействиям и высокой защитой, была поставлена задача изучить их двигательные позы при выполнении различных рабочих операций. При выполнении различных трудовых операций пожарные изучались в зависимости от: вида действия; технологического процесса; способа выполнения действия.

Keywords: personal protective equipment, special clothing, gloves, local mineral wool, mask, helmet, helmet, glasses, topography, fire extinguisher, emergency situation, thermal insulation layer, clothing package.

Ключевые слова: средства индивидуальной защиты, специальная одежда, перчатки, местная минеральная вата, маска, шлем, шлем, очки, топография, огнетушитель, аварийная ситуация, теплоизоляционный слой, пакет для одежды.

Introduction

Providing individuals with safe working conditions is one of the key tasks in the socio-economic policies of all countries. Special clothing is a widely used type of personal protective equipment (PPE) that serves to protect against aggressive environmental factors, including fire and high temperatures. Taking into account the requirements for special clothing, the development of a comfortable, safe, heat-resistant, and wear-resistant protective clothing system for emergency personnel—particularly firefighters—is a relevant issue [1–2].

It is known that currently Germany, Russia, Belarus, and China are leading in the production of special clothing for emergency service personnel. The personal protective equipment sets for firefighters produced by these countries cost on average between $600 and $1000 [4].  The significant achievements in the socio-economic development of our country are primarily associated with the establishment of new modern industries and production capacities. As a result, considerable attention is being paid to increasing the economic potential of the country, expanding the range of manufactured products and provided services, and fundamentally improving their quality [5].

Taking the above into consideration, one of the main tasks is to develop personal protective equipment with heat-resistant and wear-resistant properties for emergency personnel, including firefighters, using local raw materials, as well as to create efficient technologies for their production.

Material and methods. Personal protective equipment (PPE) is a set of items designed to protect the skin and respiratory organs from the effects of toxic substances and harmful impurities in the air. These items are divided into respiratory protection, skin protection, and eye protection equipment. Respiratory protective equipment includes gas masks, respirators, and cotton-gauze bandages. Skin protection equipment consists of protective suits designed to shield the body from harmful sources. Eye protection equipment includes special goggles. The selection of protective equipment is carried out based on its purpose and characteristics (level of protection), as well as the specific conditions of environmental contamination and the nature of exposure [3].

Personal protective equipment and special clothing are essential means used by industrial workers to prevent or minimize the negative impact of chemical substances on the human body. In addition, protective equipment ensures worker safety during hazardous activities [4–5].

Personal protective equipment is necessary for ensuring safe working conditions and preventing accidents. PPE includes the following categories [6–7]:

1. Eye protection equipment – various types of goggles that protect against toxic gases, ultraviolet radiation, and mechanical damage.

2. Hand protection equipment – special gloves that protect the skin from high temperatures and toxic substances.

3. Head protection equipment – helmets, helmet liners, hard hats, and other elements ensuring head safety. These are resistant to mechanical impacts and prevent contact of chemical substances with human skin.

4. Welding protection equipment – masks and helmets that cover the entire face during welding operations.

5. Hearing protection equipment – used in high-noise working conditions.

The classification of special clothing and personal protective equipment for firefighters is presented in Table 1 [8].

Table 1

Special Clothing and Personal Protective Equipment for Firefighters

The profession of a firefighter requires a high level of training and physical endurance. Firefighters must undergo regular training and education to be prepared for any situation. They must be able to work in a team, follow instructions, and make quick decisions. Although firefighting is a dangerous profession, it is also an honorable one, as firefighters risk their lives to save people and protect property. This gives them a sense of being useful and respected members of society [9].

Firefighters’ special clothing is designed to effectively protect the skin from open flames, water and steam, aggressive environments, as well as harsh weather conditions. Analysis of literature and scientific research shows that firefighters’ protective clothing is divided into three levels [10–12]:

Firefighters’ protective clothing (BOP – firefighting gear) – Level I (1st level).

Provides protection of human skin from extremely high (up to 400°C) and low temperatures.
Firefighters’ protective clothing (BOP – firefighting gear) – Level II (2nd level).

The material is treated with a fire-resistant compound, providing protection against high temperatures and severe weather conditions.

Firefighters’ protective clothing (BOP – firefighting gear) – Level III (3rd level).

Material: vinyl leather (type T). Protects against open flames and low-intensity hazardous factors. It is made from metallized fiberglass fabric, which provides protection against heat exposure and severe thermal damage.

A complete classification of firefighters’ protective clothing is presented in Table 2 [8].

Table 2.

Classification of Firefighters’ Protective Clothing

Research conducted on the requirements for firefighters’ gloves, which are a type of personal protective equipment, is focused on developing innovative materials that enhance heat resistance, mechanical strength, and protection against moisture and wind. The conducted research work provides for the inclusion of anatomical features in the glove design to ensure maximum hand protection in accordance with GOST R 53254-2009 (knuckles, three-finger models) [13].

Research results. It is known [14] that firefighters’ duties in emergency situations require rapid movement, the ability to put on special protective clothing within a short time, and timely arrival at the scene. Therefore, special clothing must be comfortable in all aspects: it should not be tight, must not restrict movement, and should be lightweight. For this reason, the study focused on the working processes of firefighters in Uzbekistan, their types of movement, and the structure of protective clothing systems.

Taking the above into account, visits were made to the Emergency Situations Department—specifically the Fire and Rescue Units in the Yakkasaray and Chilanzar districts of Tashkent city—where the existing protective clothing used by firefighters was studied [15–16].

Currently, a sample of the firefighters’ protective clothing used in our republic is presented in Figure 1.

Firefighters’ protective clothing uses flame-resistant fabric as the outer material. The garment features set-in sleeves, a stand-up collar, and a front fastening. The front closure includes an inner Velcro strip and an outer metal hook-button fastening. The collar is also equipped with a Velcro strap, which helps protect the neck area from fire exposure during firefighting operations. The elbow areas of the sleeves are reinforced with a protective layer made of suede fabric. The jacket includes a chest pocket with a flap and two side patch pockets with flaps. The garment is secured at the waist with a belt.

The lower part of the protective clothing consists of semi-overalls. The front section of the semi-overalls is fastened with a zipper extending above the fly. Both sides feature patch pockets. The knee areas are reinforced with flame-resistant suede protective layers.

Figure 1. Existing special clothing of firefighters

The protective clothing also includes an inner thermal insulation layer attached with a zipper. Synthetic padding (sintepon) is used as the insulating material. The sleeve ends and trouser cuffs of the thermal layer are attached to the outer layer using button fasteners.

Interviews conducted with employees and firefighters of these organizations revealed that, in emergency situations, firefighters save time by first putting on the semi-overalls over their boots and then wearing the jacket. Firefighters also identified the advantages and disadvantages of the protective clothing.

Among the advantages, the additional suede reinforcements on the elbows and knees provide protection during hazardous tasks, such as forcing open closed doors with the elbow or lifting heavy loads while kneeling. The height of the stand-up collar protects the neck area from external impacts.

One of the main disadvantages is the narrowness of the trouser cuffs of the semi-overalls, which makes it inconvenient to put them on over boots, thereby negatively affecting the speed of dressing. In addition, the thermal insulation layer made of synthetic nonwoven material tends to conduct heat under high-temperature working conditions, leading to an increase in temperature inside the clothing. During this process, heat is also transferred through the gloves, which negatively affects work efficiency.

The results of the analysis indicate that, in order to design functional, mechanically resistant, and highly protective special clothing for firefighters, it is necessary to study their movement patterns and working postures during various operational tasks.

During the performance of various work operations, firefighters’ movements are classified as follows [9]:

-by type of movement: the worker performs actions such as moving, holding equipment, and releasing it;

-by direction: depending on the situation, the worker performs active and passive movements;

-by technological process: the worker performs main and auxiliary operations;
-by method of execution: the worker performs movements using fingers, hands, legs, body, head, and eyes.

Despite the diversity of labor processes, any manual work consists of four main types of movements performed in combination. These include: movements aimed at grasping or holding objects or individual parts of tools with the fingers; movements involving the relocation of objects or tool components, including reaching, and coordinated actions of the hands, legs, and body; supporting movements aimed at maintaining the position of an object relative to other objects or equipment; and movements aimed at releasing the hand from an object or a part of a tool [17].

The analysis of a worker’s posture and movements during the performance of labor functions determines the level of comfort of special clothing. It is known [18–19] that population size typology is developed based on static measurements of the human body. The analysis of relevant movements and postures makes it possible to determine the necessary dynamic allowances in body dimensions when designing special clothing. This ensures freedom of movement for firefighters and reduces physical fatigue. If characteristic human movements are not taken into account in the design of protective clothing, it may restrict movement and cause discomfort.

Based on studies conducted in this field and interviews carried out in the “Emergency Situations Department – Fire and Rescue Unit,” the ergonomic movement types of firefighters during firefighting operations were analyzed, and corresponding schemes were developed (Table 2) [9].

The conducted research showed that during the work process, personnel are required to move in various postures. Firefighters must extinguish fires and rescue victims within a short period of time. An analysis of the existing protective clothing during operation revealed that, during professional activities, the following types of damage may occur in different areas of the garment:

-when moving the arms sideways and upward, нагрузка falls on the back width of the jacket, leading to wear of the armhole seams;

-when using firefighting equipment and moving the arms sideways and upward, stress is placed on the sleeve width and sleeve attachment seams;

-as a result of bending, sitting, running, climbing up, and moving downward, wear occurs in the crotch seams of the semi-overalls;

-during work with necessary equipment, damage may occur to the metal hooks of the outer fastening of the clothing, leading to deterioration of their attachment points;

-in the semi-overalls, stress is applied to the middle seam of the back section at the sitting height area;

-during firefighting operations involving lifting and moving loads, wear occurs in the side seams and palm areas of the gloves.

Analysis of research results. The overall appearance of the firefighters’ clothing set is shown in Figure 2, and the wear and tear topography is illustrated in Figure 3.