# An Overview of Tools and Challenges for Safety Evaluation and Exposure Assessment in Industry 4.0
## 1 Introduction  
Based on reported data from the International Labour Organization (ILO) [1], approximately 1 billion workers and operators every year are exposed to hazardous chemicals, including dust, fumes, and vapours, in their working environments, leading to illnesses or even fatal diseases. Workers are susceptible to exposure to a series of different airborne hazards depending on the processing materials and manufacturing procedures. Work-place airborne contaminants include the release of particulate matter (PM), volatile organic compounds (VOC) and semi-volatile organic compounds (SVOC) from equipment and operating machines, which could cause skin and eye irritation and respiratory inflammation [2]. PM is also associated with harmful effects on the respiratory tract, while their effect on human health is related to their size, since the smaller the size, the more prone to navigate through bronchioles and deposit in the alveoli [3]. Work practices such as polymer thermal processes [4], grinding [5], welding [6], as well as agricultural and wood-related dust, gases, vapours, fumes, and crystalline silica could lead to respiratory diseases such as pneumoconiosis and silicosis, while exposure to asbestos could lead to asbestos and other fatal disorders [7, 8].  
The shift of manufacturing processes towards digitalisation and the use of the automation and interconnection of different devices and equipment is described as \"Industry 4.0\" or \"4 th industrial revolution\", signifying the development of smart factories and systems generating and analysing data for process optimisation [9]. The smart factory market is considered to be worth approximately USD 100.6 billion in 2024 and it is projected to reachUSD 164 billion by 2029 with a significant compound annual growth rate of 10.3% [10]. In the Industry 4.0 concept, the use of smart and autonomous systems exploits the technological advances of artificial intelligence (AI) and machine learning (ML) analytics, advanced manufacturing procedures, such as 3D printing and real-time connection and communication between computers and machines through the concept of Internet of Things (IoT). These technologies lead to the demand of novel and dynamic health and safety systems to support employees in their tasks [9].  
The use of automated technologies is considered to promote workplace safety, especially through the replacement of humans by robotic systems, continuous data analytics to monitoring employees' well-being, and the development of ergonomic and comfortable workplaces and smart personal protective equipment (PPE) [11]. [PERSON] et al. [12] reviewed the positive and negative impacts of Industry 4.0 technologies on occupational safety, signifying the potential improvements in occupational environments and the health of employees, while there are alarming concerns on increased stress, fatigue, and psychosocial risks. [PERSON] et al. [13] analysed the used of advanced technologies and wireless monitoring and sensors as tools for improving health and safety in the construction industry of Malaysia. Similarly, the use of wearable technology has been investigated as part of health and safety monitoring on site, providing input on physiological data, environmental sensing, and proximity detection and tracking [14,15].  
In this study, the various tools of the Industry 4.0 concept are reviewed, while comparing their characteristics with occupational health and safety assessments. This perspective highlights the applicability of the technologies in monitoring and evaluating airborne hazards and supporting exposure assessments conducted onsite by safety professionals, promoting a safer occupational environment. Finaly, the potential challenges of the exposure assessments to airborne hazards in Industry 4.0 are summarised, addressing the needs and areas of further research and refinement on innovative exposure assessment tools.