# Wearables for Industrial Work Safety: A Survey
## 3 State-of-the-Art Techniques in the Field of Industrial Wearables
### Data Collection and Wearable Metrics  
The monitoring function is based on the collection of several metrics. In fact, no classification of metrics collected by wearable devices is currently available in research works. We, thus, divide these metrics into two groups depending on the data collected from wearables. The first group is related to the data \"extracted\" from the human body, and the second group deals with the environment's information. Tables 3 and 4 represent the most common wearable metrics and their classification. In industrial scenarios and setups, the most important and frequent metrics related to the human body are temperature, heart rate, and location. Less commonly used metrics are motion and perspiration. However, the motion metric is essential for industries associated with lifting heavy loads (construction, logistics), and the perspiration can also be relevant for industries with a high probability of heat stress (e.g., mining) [44]. To the best of the authors' knowledge, the rest of body-related metrics such as EEG, EMG, ECG, heart sounds, sleeping activity, etc. are not tracked in the industries yet, but they can help estimate both the worker's physical and mental readiness for the industrial process. Developing a comprehensive, lightweight, wearable solution consisting of multiple sensors capable of \begin{table}
\begin{tabular}{p{71.1 pt} p{142.3 pt} p{142.3 pt}} \hline \hline
**Industry Branch** &
\begin{tabular}{c} **Functions** \\ **(See Table 1)** \\ \end{tabular} & \multicolumn{1}{c}{**Examples of Applications**} \\ \hline Mining & M, Tc & US-based Guardhat to prevent injuries combining rugged helmets with microphones, cameras, and track sensors [42]. Guardhat is currently integrated into a lot of mining operations. \\ \hline Chemical & M, Tc & MyExposome developed wristbands that can detect chemical exposures during the day [34]. \\ \hline Forest products, construction & M, Tc, S & SolePower company released smart boots [41]. It is equipped with many various modules, particularly GPS and RFID, to determine the wearer’s location. Besides, they are very durable, so they can easily withstand many ordinary adverse external influences. \\ \hline Crude oil production & M & Smart Helmet by VRMedia Srl. was applied by the third-largest oil and gas service company in the world Baker Hughes to reduce downtime and increase safety at the workplace [43]. \\ \hline Transportation, Shipping & M, Tc, S & Kinetic presents a wearable device called REFLEX that is equipped with sensors and modules performing biomechanical analysis [36]. It is worn on the belt or waistband and can determine whether the posture is correct or not and notify the user by vibration when risky movements arise. \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Industry branches and inherent industrial wearable functions. measuring the human body's vital parameters as possible will make a significant contribution to eliminating accidents due to human error in hazardous industries. Regarding the parameters related to the environment, it is hard to say what metrics are more frequently used. The industrial conditions define wearable devices' choice and, consequently, the metrics that can be collected. In the reviewed literature, temperature, relative humidity, and air quality are often used as environment metrics.