There is a buzz in the world of safety and health clothing -- and it was generated by the word "wearables". Advances in technology could move personal protective equipment (PPE), customarily at the bottom of the hazard control hierarchy, upward as a means of reducing hazards.
People invest their own money in devices to track their hiking routes, monitor their heart rates or measure their progress towards running marathons. This increased demand for trackers and sensor-based health monitors in the domestic market has increased production, driven down unit costs, and made workplace wearables more affordable.
They have also become more comfortable. Only ten years ago an article in Applied Ergonomics (Knight et al, 2007) raised concerns that body-worn technology weighing 500 g or more would lead to rapid fatigue, poor posture and increased musculoskeletal problems. Now that a typical smart watch weighs less than 100 g, including its long-life battery, such fears have dwindled.
Batteries with a life span of up to two years make it possible to incorporate technology into protective workwear, since the clothing will usually be replaced before the battery runs out. Sensors to measure noise, light, dust and temperature have also become smaller and more accurate. In parallel, the "internet of things" has improved connectivity through Wi-Fi, Bluetooth and radio frequency identification.
The growth of domestic fitness trackers has helped to increase acceptance of workplace monitoring. When commercial drivers were told that their vehicles would have to be fitted with tachographs -- or as Dennis Skinner MP described them in 1979 "the spy in the cab" -- they went on strike in protest. Some lone working devices and early vehicle telematics were resisted because of suspicions that the technology was there to track work, not to protect workers. But now many people are happy not only to wear tracking technology for their own information, but to share the data with friends on social media or use it to compete against strangers.
The purpose of tachographs was to prevent tired drivers crashing lorries, not to assess their work-life balance and stress levels. But an increased awareness of the health effects of noise, dust, vibration and stress has given us another reason to look harder at what wearable tech can do for us.
What follows is a guide to what is available and what might be coming soon.
Previous fatigue monitoring systems relied on behaviour, such as nodding heads, which might occur late on in the fatigue process. However, measuring voltage fluctuations in the brain can give an earlier indication that concentration is dropping. Electroencephalography (EEG) machines that measure these fluctuations used to operate only in hospitals and sleep labs, but an Australian company, SmartCap (http://www.smartcaptech.com/), has brought the sleep lab in miniature form to the workplace.
The LifeBand can be worn inside a baseball cap or hard hat and is used in mining and haulage operations. Information transmitted by Bluetooth can be displayed inside the lorry cab, to warn the driver that they need a rest. Fleet managers can also view the data over the mobile phone network.
The technology would be equally applicable in a factory or construction environment where operation of lifting equipment or other machinery requires full attention and alertness (bit.ly/2vHQKZM).
You might miss an alarm on your smartphone but a red light flashing in front of your eyes because you've reached your noise or vibration limit is harder to ignore. Heads Up Safe (www.headsupsafe.com) has developed this technology in the US, with three lights attached to the edge of safety glasses that can be coded to provide different warnings.
Google Glass was the light that failed as a heads-up data display in the consumer market earlier this decade but the idea of augmented reality it introduced more widely is too valuable to disappear. In the workplace it can overlay objects in front of an operator or maintenance technician with information that might otherwise be hidden in a manual, risk assessment or method statement. Information can be triggered by location sensors or by voice commands, leaving the user's hands free. The correct information can be overlaid on the appropriate knob, lever or access hatch.
If a technician needs additional support, "see what I see" systems such as Skylight (bit.ly/2uXIxzL) enable images to be shared with a support function located remotely from the workplace. Communication systems built into the goggles allow support staff to talk the technician through any difficulties.
A version of Google Glass, Glass EE, is already being used in workplaces in the US (bit.ly/2uZqfxx). Though its primary function is not safety, wearables whose work and safety functions are integrated are likely to come soon.
The limitations of standard issue hearing protection are well documented. Customised moulded earplugs that also act as earphones are already in use, particularly among technicians in the music industry who want to hear particular sounds, but to limit those from other instruments. In Canada, EERS (www.eers.ca) is going further when measuring exposure to noise by assessing not just the ambient sounds but also the efficiency of the hearing protection.
EERS founder Nick Laperle says that the company intends to assess the usefulness of measuring other biometrics inside the ear, such as body temperature, heart rate and breathing rate. The devices will be able to upload and collate information from all employees throughout a shift, providing a way of monitoring personal data and noise around a workplace.
In your hands
Being able to see virtual or augmented worlds is fine for information, but there is sometimes benefit from being able to feel what is going on. "Haptic" feedback through gloves can provide your hands with the sensation that you are actually carrying out a task. The technology has been developed to help surgeons practise keyhole procedures before working on patients, but applications for technicians to undertake complicated maintenance jobs can be imagined easily too.
Many safety training simulations rely on pointing and clicking with a handheld device, but pointing at a virtual fire extinguisher and clicking a remote control is unrealistic. HoloLens uses gestures to control the interface -- the glasses know what the user is looking at, and can read whether the gesture is an "air-tap" or a "bloom" (bit.ly/2uzlQxE). Perhaps future training suits will include whole-body haptic feedback to simulate the weight of an extinguisher and the pushback when it is triggered.
Data from body-worn sensors is collected in real time and analysed to identify repetitive movements, providing evidence for task redesign
If you're not keen on gesturing in mid-air in the style of Tom Cruise in Minority Report, the lower arms offer another possible input device, with "smart tattoos" that can be attached temporarily to a user's skin to provide a portable control panel (bit.ly/2wgcBHz).
Also designed to be attached to the lower arm is Steer (kck.st/2u1KJSk), a device in development after it was four times over-subscribed on the Kickstarter crowdfunding site, that measures a driver's heart rate and skin conductance. If it detects changes consistent with the wearer falling asleep, it triggers a small electric shock.
Noise, radiation, gas and air quality measurement devices worn on the body have become standard issue in some industries. These devices have become smaller and more comfortable to wear, as well as more connected, so data can be monitored in real time, rather than downloaded at the end of a shift.
Another development has been location tracking and proximity warning systems. A tag sewn into the high-visibility jacket of a pedestrian can be detected in a vehicle to warn the driver when people are nearby (bit.ly/2vM35J7).
Traditional high-visibility clothing is a compromise patchwork of fluorescent for daytime with reflective strips for night, which work only if there is light to reflect. Some manufacturers have started to offer hi-vis vests and helmets with built-in high-intensity lighting, making workers more visible at night, as well as providing them with hands-free working lights.
The next step might be work clothing that could adapt to ambient lighting conditions -- working out when to become fluorescent, or reflective, or when to turn on the lights.
Musculoskeletal disorders account for around 40% of reported work-related illnesses. The evidence is that simply training people to "lift properly" when manual handling or to "sit properly" when using a computer is ineffective.
Systems from Heddoko in Canada (bit.ly/2eQ5lee) and dorsaVi in the UK (bit.ly/2tFHuRa) incorporate sensors that measure movement as well as muscle activity with pads worn on the back. The activity data is collected in real time and can be analysed to identify challenging or sustained postures or repetitive movements, providing evidence for task redesign.
Snickers Workwear was started in the 1970s by a frustrated electrician who couldn't buy the clothes he needed for work, so he arranged to have them made. Snickers has identified that one continuing problem with trousers worn when kneeling is that workers don't change the knee pads as often as they ought to and damage their knees.
Snickers is developing a technological answer to this problem. Its prototype, Tracker 1, includes a microchip fitted to a pair of work trousers to monitor knee impact. Instead of relying on a calendar cycle to replace kneepads -- which can be inefficient -- or on wearers to notice for themselves, a worker can receive an alarm on a connected mobile phone after a set number of impacts, warning them to change the protection. Future versions could link this data with procurement processes to maintain stocks of knee pads.
Up the hierarchy
Hearing protection backed up with annual surveillance to measure whether deafness has increased over 12 months remains at the bottom of the control hierarchy. But if it incorporates technology to raise an alarm when noise exposure is exceeded on a single shift it becomes a means of reducing exposure. Similarly, the data from body-worn accelerometers that measure bending and stretching can be used to improve training and monitoring by using constant direct measurements of muscles, rather than relying on sample observations.
Unlike PPE that protects an individual, wearable technology has the potential to gather data to protect a population -- identify which areas are the noisiest, which tools have the most vibration or which areas involve the most awkward lifting tasks.
Its value will come from further integration. Rather than separate monitoring systems for noise, fatigue, location, movements and so on, a single system that can take all the data and provide the right people with information to manage safety and productivity could have enormous benefits.
For example, pick up your respirator and a heads-up display shows you how to perform pre-use checks; walk into a workplace and your earpiece checks whether you have the right PPE and provides an audio message if you don't.
Ignoring advances in wearable tech is not an option. Although current UK Health and Safety Executive advice is that "continual monitoring and recording of vibration exposure... is probably not a good use of your or your employees' time", there is evidence that continuous monitoring is more reliable than an assessed, generic value. As it becomes more practical to measure everyone, casual observation of manual handling or PPE usage might no longer be enough.
As wearable devices and the analytic software that decodes its readings become cheaper, what is reasonably practicable will change. In the next ten years, it's possible to envisage court cases in which failure to control a significant hazard using widely available wearable technology is a significant factor in the prosecution's case.