Workplace Wearable Devices
When considering the use of digital technologies for managing OSH, account should also be taken of the role of other electronic devices that can be worn by workers, commonly known as “wearables” or “wearable devices”. These devices do not provide any direct protective functions in the way that traditional PPE do, but their measurement, monitoring and control functions can be successfully applied to detect hazards and reduce risks in the workplace (Choi et al. 2017; Awolusi et al. 2018; Dolez et al. 2018; Barata and da Cunha 2019).
According to the definition proposed in draft standard IEC 63203-101 EDI (IEC 2019a) wearable electronic devices constitute an “electronic device intended to be located near to, or on a human body. These devices can be provided with artificial intelligence functionality and/or can be part of a widely connected system. These devices can be used to perform a variety of tasks”. Investopedia (2020a) defines these devices in more concrete terms as a:
category of electronic devices that can be worn as accessories, embedded in clothing, implanted in the user’s body, or even tattooed on the skin. The devices are hands-free gadgets with practical uses, powered by microprocessors and enhanced with the ability to send and receive data via the Internet.
Wearable devices used in the workplace can be classified taking into account their physical form, location and manner of wear, as well as functions based on various physiological parameters, working environment parameters and other data generated by machines or processes operated by workers. For example, one of the classifications proposed by Mardonova and Choi (2018) distinguishes the following types of wearables: smartwatches, smart eyewear (smart glasses), fitness trackers, smart clothing, wearable cameras and wearable medical devices. Wearables can also be classified according to the location where they are worn or fixed to the body of a person or the clothing. In this case, such location areas as the head, ears, eyes, torso, arms, wrists, legs, and feet can be distinguished. But wearables may also be implantable into various parts of human body, and be multifunctional, i.e. they can be worn on different parts of the body depending on the user’s needs.
The main areas of wearables applications with benefits for employers and workers include, among others, monitoring psychological and physiological factors, enhancing operational efficiency, collaborating, promoting work environment safety and security, performing industrial designing, and improving the health of workers (Khakurel et al. 2018). Among many cases of practical application of non-PPE wearables to OSH-related purposes that have been described in the literature, the following two examples can be mentioned: applying the Philips Health watch for monitoring the physical activity of workers within the We@Work project (Abtahi et al. 2017), and a study on the implementation of the Microsoft HoloLens® mixed- reality device at construction sites to improve work-related hazard identification and risk communication (Dai and Olorunfemi 2018).
Smart PPE Functions and Typology
As mentioned above, recent developments in the fields of enabling technologies has allowed PPE to be equipped with a number of new useful functions that did not previously exist in traditional PPE solutions. In particular, these functions include: monitoring the health of workers by measuring key physiological parameters (e.g. body temperature, heart rate, respiratory rate, etc.); monitoring work comfort at work (e.g. underclothing temperature and humidity, work position); geographical location of workers with regard to potentially dangerous physical objects or high-risk zones; monitoring the current status of PPE protective properties and the degree of wear; notifying workers and/or their safety managers about current hazards or the level of risk (e.g. by means of a personal digital assistant or smart glasses); and activation of protective systems or deactivation of sources of risks after exceeding a high-risk threshold value. The above-mentioned smart PPE functions, which are performed in addition to the basic protective functions, can be divided into three main types: (1) sensing, (2) activating risk controls, and (3) ensuring correct operation of PPE items, as shown in Table 6.1.
Depending on the number and nature of functions performed, the type of technology used to build smart PPE, and the extent to which these systems affect OSH in terms of the number of controlled environmental factors or the number of workers to be monitored and protected, three levels of complexity of these measures can be distinguished:
- 1) simple smart PPE;
- 2) autonomous smart PPE systems; and
- 3) smart networked PPE systems.
Such a division reflects both the diversity of smart PPE solutions from the point of view of their structural complexity and the level of intelligence that should be
Main Types of Additional Functions Provided by Smart PPE
Activating risk controls
Ensuring correct operation
adequate to the functions performed. The next sections provide a brief description and examples of solutions relating to each of these levels.
Simple Smart PPE (Level 1)
Level l covers relatively simple PPE solutions based on the use of smart textiles and other smart materials, such as phase-change materials (PCM), shape-memory alloys, thermoelectric materials and others. The basic functions of these solutions are to detect changes in the physiological parameters of users and the parameters of the surrounding environment and to react autonomously to these changes by adequately adapting the protective functions according to the general concept shown in Figure 6.1. Level 1 PPE products may also consist of some relatively simple analogue and digital electronic modules to provide dedicated functionality, but the processing of signals in such modules is usually limited to measuring a few' input parameters, processing them according to the appropriate transformation functions, and then generating the output signals to achieve the desired state of protection against specific hazards.
FIGURE 6.1 General concept of self-adaptive functions of simple smart PPE (level 1)
Level 1 smart PPE enables one to control only a single or, at the most, a few risks at a time, and their range of impact affects only individual users. Often these solutions are not ready-to-use products but are offered as to be considered as components for PPE items which provide traditional protection in a traditional manner, i.e. based on materials and devices that are not self-adaptive to environmental changes. Since these solutions do not contain ICT modules, they do not generate or transfer any data that could be used to perform more advanced functions within the overall OSH management system.
An analysis of the scientific literature and a review of commercial offers from PPE manufacturers show that there are already many different smart materials and smart PPE products on the market, which are able to effectively adapt protective parameters to changes in the working environment without the support of sensor technologies and the ICT. One of many examples of such solutions is self-thermo- regulating garments constructed of a material consisting of microcapsules containing phase-change material, which is designed to cool the body of a person working in a hot working environment or wearing impermeable protective clothing (Bartkowiak et al. 2013). Another example is a prototype of industrial safety helmet equipped with a cooling PCM layer and a simple electric fan-based system of forced convection to control the thermal comfort of users (Ghani et al. 2017).
Autonomous Smart PPE Systems (Level 2)
Level 2 corresponds to autonomous smart PPE systems, which are the intermediate solutions between level 1 and level 3 systems. Level 2 systems can consist of multiple embedded sensors, activators and control electronic modules. These systems can detect different hazards in the working environment and monitor risks associated with various physical, chemical, biological, etc. factors, but they can also monitor the proper functioning and end-of-service-life of individual system modules. At the activator level, the operation of level 2 systems involves primarily the adaptation of protective functions to mitigate the risks associated with detected hazards, but may also involve communicating the level of risk and related warnings to the worker, as well as triggering the operation of external risk reduction devices or systems that perform the functions of so-called engineering controls or, in equivalent terms, collective protection measures.(Figure 6.2).
The autonomy of the level 2 smart PPE means that they can properly perform all their essential protection functions without any connection to an external controller or data server (such as cloud-based systems). Such systems may be equipped with ICT modules for processing measurement data, but the collection, transmission and processing of these data will in this case be limited to the cyber-physical sphere of a single user, referred to as the Body Area Network (BAN), or possibly to the sphere of several smart PPE users operating locally near each other.
An example of level 2 smart PPE is a high-visibility smart vest equipped with sensors to detect workers approaching danger zones, and/or detect vehicles such as fork-lift trucks or automated guided vehicles approaching workers (Elokon 2019). The detection of potential collisions by such smart vest can trigger acoustic and visual alarm signals and send a signal to an approaching machine in order to limit its
FIGURE 6.2 The concept and main functions of autonomous smart PPE systems (level 2)
speed or stop. Another example of a level 2 solution is the Dainese protective jacket which is equipped with fall detectors, inflating airbags and a pneumatic system activated automatically during a fall (Ridden 2017). The airbags are suitably positioned around the human body to provide protection for those parts of the body that are at risk of injury when falling from a height not exceeding two metres.
Despite discussing the above examples of smart PPE systems, level 2 systems should be considered as a certain thought construct or transitional stage, which is introduced in order to organise and describe the complexity and role of various smart PPE solutions in OSH management, rather than a clearly identified category of smart PPE represented by a set of products introduced for use in specific workplaces. In view of the rapid development of industrial IoT technology, in particular wireless communication technology and edge- or cloud-based data processing services, and the increasing use of non-PPE wearables in the workplace, level 2 applications are not found frequently in the literature, as they are actually a special case of the more complex and effective level 3 systems that are described in the next section.
Smart Networked PPE Systems (Level 3)
Smart networked PPE systems are a specific type and area of application of smart networked systems (SNS) dedicated to different working environments to improve the safety, health and/or comfort of workers. SNS can generally be defined as collection of spatially and functionally distributed embedded computing nodes that are interconnected by means of wired or wireless communication infrastructures and protocols (Podgorski et al. 2017). Such systems consist of a large number of interconnected sensors, activators and ICT modules, can be connected with external (e.g. cloud-based) or local processing servers, and on this basis can provide real-time collection, processing and analysis of large measurement data streams from multiple users and other smart objects covered by an industrial IoT network. The concept of such a system is shown in Figure 6.3.
As shown in Figure 6.3, level 3 systems can, to some extent, be considered as a network of interconnected level 2 systems. Such infrastructure can also include a master node that conducts coordinative functions and calculations for the whole system. Thus, level 3 smart PPE systems can simultaneously control many different
FIGURE 6.3 General concept of smart networked PPE systems (level 3)
risk factors in the working environment, risk control functions may cover many users at the same time, and, in the case of using advanced data analytics and context- awareness methods, these systems can support the implementation of advanced OSH management functions. The extended range of functions of smart networked PPE systems makes possible their integration into industrial IoT covering production machines and devices, industrial robots, collective protective systems and other smart objects existing in a given working environment.
Such advanced smart PPE systems representing the third level of system complexity are not yet widely used in the workplace, but more and more research centres and high-tech companies are carrying out research and pilot testing in this area. As a result, the first commercial offerings of such systems are already available on the market. One example is the Corvex Connected™ platform developed and offered by Corvex Connected Safety (Webb 2019). This technology enables data to be transferred between the smart PPE items w'orn by workers and a network of beacons placed at different locations in the workplace. The area monitored by this system can be divided into appropriate zones where different requirements with regard to safety and health and the use of PPE may apply. Each worker is equipped with a unique Corvex handheld device that allows real-time notification of current risks at their workstations, as well as providing instructions on how to use the appropriate PPE.
Another example of the implementation of the smart networked PPE system is Maximo Worker Insights application developed by IBM on the basis of the IBM Watson platform in co-operation with Garmin Health, Guardhat, Mitsufuji and SmartCone (Vinoski 2019). The aim of this platform is to monitor such potential hazards occurring in the work environment as heat, temperature, gas levels, and working at height, and to assess the associated risk on the basis of measurement data collected from the workplace and the sensors worn by workers. Biomonitoring of workers is going to be provided by Garmin’s fitness tracker and Mitsufuji’s smart shirt. The Guardhat safety helmet, on the other hand, will make it possible to monitor the physical conditions around the worker and warn him/her about the detected hazards. Finally, SmartCone technologies are going to enable the separation of safety zones in the workplace and the measurement of environmental noise and temperature levels. It is claimed that the potential advantage of this system is the ability to use the high analytical power offered by the IBM Watson platform for analysis and multifaceted inference based on large amounts of data obtained simultaneously from many different sources of the working environment with the use of various measuring devices and technologies.