Every year in France, thousands of lone workers are victims of accidents with no witnesses. The lone worker device, also called PTI-DATI, is an alert system capable of detecting a fall, prolonged immobility, or discomfort and automatically notifying emergency responders. Whether you are an executive, HSE manager, or HR manager, understanding how this device works and the obligations associated with it has become essential. You can learn more about this device to find out more.
What is a lone worker device?
The lone worker device refers to a connected safety device designed to monitor the activity of a lone worker in real time. Despite its name, the purpose of this device is precisely to save lives: by detecting an anomaly (loss of vertical position, lack of movement, discomfort), it automatically triggers an alert to a monitoring center or a designated manager.
The acronyms PTI (Lone Worker Protection) and DATI (Lone Worker Alarm Device) are commonly used to refer to this same type of equipment. The term "PTI" encompasses all prevention measures, while "DATI" focuses on the alarm device itself.
💡 Key takeaway: PTI = the full set of protection measures. DATI = the specific alarm device. Lone worker device = the common name for the automatic immobility detection function.
How does a lone worker device work?
The principle is simple but highly effective. The device, worn by the worker (on the wrist, on the belt, as a badge, or via a smartphone app), includes sensors that continuously analyze the movements, position, and activity of its wearer.
The process in 4 steps:
📡 Active sensors → ⚠️ Anomaly detected → ⏱️ Pre-alert → 🚨 Emergency alert
Types of alarms
There are two main categories of alarms in a lone worker device:
- Automatic alarm: triggered without any action by the wearer. The device detects a loss of vertical position (fall), prolonged immobility, or a lack of movement for a configurable period of time. If the worker does not deactivate the pre-alert within the allotted time, the alert is sent.
- Manual alarm (SOS button): the worker deliberately presses an emergency button in the event of danger, assault, or a feeling of discomfort. The alert is immediate.
Geolocation: an essential complement
Detecting a problem is not enough: encore must be able to locate the worker to send help quickly. Modern devices integrate outdoor GPS geolocation and Bluetooth or radio beacon systems indoors. Some equipment continuously records the GPS position, which makes it possible to provide a recent location even in a building where the signal is weak.
What does the law say? The employer's obligations
In France, the Labor Code requires employers to ensure the health and safety of their employees (Article L.4121-1). More specifically, Article R4543-19 states that a lone worker must be able to report any distress situation and be rescued as quickly as possible.
⚖️ Imporant: The law does not directly require the use of a man-down device. However, the employer has a legal obligation to put in place the necessary means so that a lone worker can be rescued quickly. The PTI-DATI device is now the most reliable way to meet this obligation.
Failing to take these obligations seriously exposes the employer to legal action in the event of an accident. The company's civil and criminal liability may be incurred if an isolated employee suffers harm and no appropriate protective measures had been put in place.
Who is considered a lone worker?
A lone worker is anyone performing a task away from the sight or voice range of their colleagues, either temporarily or permanently. This applies to a very important number of professional situations:
- Maintenance technicians and field service technicians
- Night watchmen and security guards
- Construction workers on job sites
- Hospital staff on night rounds
- Delivery drivers and truck drivers
- Office employees working nonstandard hours
- Cleaning staff working alone
The different types of man-down devices
The market now offers several formats of PTI-DATI devices, adapted to the constraints of each profession. The choice depends on the work environment, the identified risks, and the confort of the employee.
| Device type | Benefits | Use cases |
|---|---|---|
| Dedicated PTI device | Robust, self-contained (up to 30 days), IP67 certified | Industry, construction, logistics |
| Connected PTI watch | Discreet, silent alert, real-time tracking | Security personnel, hospital settings |
| PTI belt | Ergonomic, optimized fall detection | Construction sites, working at height |
| Smartphone app | Cost-effective, no additional equipment | Traveling sales reps, delivery drivers |
| Smartphone / PTI phone | Built-in, non-removable feature, hands-free calling | Versatile, all sectors |
Criteria for choosing the right PTI-DATI device
Choosing a lone worker device should not be left to chance. Several key parameters need to be assessed in advance.
1. Work environment
Noisy areas, the presence of dust, splash risks, working at height, or in confined spaces: each situation requires a different level of ruggedness. An IP67 protection rating (water and dust resistance) is recommended for industrial environments.
2. Network Coverage
The device must be able to transmit alerts under all circumstances. Check the availability of the GSM network at your site. For areas without coverage, prefer equipment compatible with multiple operators (Orange, SFR, Bouygues, Free) or equipped with radio beacons for indoor location.
3. Alert Management
Three management modes are possible:
- Internal management: alerts are received by colleagues or an internal security manager via call/SMS escalation.
- 24/7 remote assistance: a professional monitoring center receives the alerts, carries out verification, and contacts emergency services if necessary.
- Hybrid mode: combination of the two approaches depending on working hours and situations.
4. Comfort and ergonomics
A device that hinders the worker will not be worn. It must be lightweight, compatible with other personal protective equipment (PPE), and have an accessible physical SOS button even while wearing gloves.
The concrete benefits of a lone worker device
Beyond regulatory compliance, deploying a PTI-DATI system offers tangible benefits for the company and its employees:
- Reduced response time: thanks to automatic detection and geolocation, emergency services are notified immediately and know exactly where to go.
- Regulatory compliance : the employer demonstrates due diligence in safety and reduces legal exposure.
- Peace of mind for teams: isolated workers know they are never completely alone. This sense of security improves morale and productivity.
- Centralized management: Modern platforms make it possible to monitor all devices from a single interface, with alert history and reports.
Best deployment practices
Implementing a lone-worker device is not limited to distributing equipment. A structured approach ensures the system’s effectiveness:
- Assess the risks: identify all lone-working situations in the company and the associated hazards (fall, assault, illness, hazardous environment).
- Choose the appropriate device: based on the environment, the available network, and operational constraints.
- Train employees: each equipped worker must know how to use their device, understand the alert procedures, and understand the importance of carrying it at all times.
- Organize the emergency response chain: define who receives alerts, the verification procedures, and the response protocols.
- Test regularly: carry out simulations to verify the system is working properly and that responders react quickly.
FAQ — Frequently Asked Questions about the lone-worker device
Is the lone-worker device mandatory?
The law does not require a specific device, but it does require employers to put in place all the measures necessary so that a lone worker can be rescued quickly. In practice, the PTI-DATI device is the most widely used and most reliable solution for meeting this requirement.
Which sectors are affected?
All sectors are potentially affected whenever an employee works alone: construction, industry, logistics, healthcare, security, cleaning, maintenance, field sales, agriculture, and even office-based roles for employees on staggered hours.
Can a smartphone app replace a PTI unit?
A PTI app is an economical and practical alternative, especially for mobile workers who already have a smartphone. However, it depends on the phone’s battery life and network coverage, and it can be uninstalled. For high-risk environments, dedicated PTI units or belts offer superior reliability.
What happens in the event of a false alarm?
Modern devices include a pre-alarm phase: before triggering the alert, the system emits a sound or vibration signal that the user can cancel. If it is triggered, the monitoring center carries out a "verification call" (audio call) to confirm or rule out the emergency situation.
How much does a PTI-DATI device cost?
Prices vary depending on the type of equipment: from a few euros per month for a smartphone app to several hundred euros for a professional PTI device with a teleassistance subscription. The investment remains very low compared with the human and legal consequences of an accident that is not taken care of.
Conclusion
The lone worker device is not just a simple technological gadget: it is a concrete commitment to the safety of your employees. Faced with the risks inherent in working alone, it is now the most effective solution for ensuring rapid response in the event of an accident and complying with the employer's legal obligations. Whether in the form of a device, a watch, a belt, or a mobile app, PTI-DATI solutions have become more reliable, more ergonomic, and more accessible. It is now up to every company to take up the issue and protect those who work in the shadows.