PTI (DATI) Phone: How It Works and How to Choose the Right Device

A PTI phone (Protection du Travailleur Isolé – lone worker protection) is a device designed to detect dangerous situations involving a lone worker and automatically trigger an alert to emergency responders, a supervisor, or an alarm monitoring center. It uses sensors such as an accelerometer, gyroscope, and GPS to continuously monitor the user's condition and movements.

When an incident occurs—a fall, medical emergency, loss of verticality, assault, or prolonged lack of movement—the device triggers an alert, allowing emergency responders, a supervisor, or an alarm monitoring center to be notified quickly.

In everyday use, there are two main categories:

GSM DATI (Dispositif d'Alarme pour Travailleur Isolé – lone worker alarm device) refers to a dedicated physical device designed exclusively to protect lone workers. Robust and self-contained, it has built-in alert functions. It is a reference solution in industrial environments.

PTI smartphone

This solution relies on an application installed on an Android phone or iPhone. Depending on whether the application is native (pre-integrated by the manufacturer) or simply downloadable, the levels of reliability and legal responsibility can differ considerably.

Under U.S. workplace safety regulations, employers have a general duty to provide a workplace free from recognized hazards likely to cause death or serious physical harm. OSHA does not have one general standard requiring every lone worker to carry a PTI/DATI device, although specific industries and work situations may be subject to additional requirements.

Some manufacturers offer smartphones in which the PTI application is directly integrated into the device's firmware. It cannot be uninstalled, disabled, or bypassed by the user: it is an integral part of the device, just like the camera or GPS module.

For employers, this is an essential safeguard: protection remains continuously active and does not depend on employee behavior. This type of device meets the strictest reliability requirements, particularly in high-risk sectors such as manufacturing, construction, maintenance, security, and night work.

Key benefits:

• Continuous active protection
• No risk of accidental or deliberate deactivation
• Reduced risk of human error
• Centralized equipment management
• Evidence that an appropriate protective measure was provided by the employer in the event of an accident

This is now the preferred choice in many high-risk environments, including manufacturing, energy, private security, technical maintenance, and night work.

Another often overlooked advantage is user acceptance. Employees use a conventional smartphone with a familiar interface while benefiting from PTI functions running in the background.

Some companies choose to install a PTI application through the App Store or Google Play on an employee's personal phone. Rapid deployment, limited investment in hardware, and no need to purchase additional devices make the benefits immediately apparent.

However, this solution has genuine limitations that are often underestimated. An application can be uninstalled or disabled, deprived of the permissions it needs, disrupted by a system update, or simply closed in the background to save battery life.

If the system were no longer operational when an accident occurred, the employer could face significant consequences. The short-term savings could prove very costly in the event of an incident.

This is why health and safety managers generally favor professional, controlled solutions, particularly where occupational risks are high.

A PTI phone can trigger an alert in several ways, depending on the level of risk and the scenarios identified during the workplace risk assessment.

Manual activation

The employee deliberately presses a dedicated SOS button.

Example: a security officer facing an assault can trigger a silent alert without attracting the attacker's attention.

Inactivity detection

The system detects a prolonged lack of movement for a configurable period of time.

This mode is particularly useful for:

• night patrols;
• isolated workstations;
• technicians working alone.

Example: a maintenance technician becomes unconscious following a medical emergency without experiencing a violent fall. The absence of movement for 45 seconds automatically triggers an alert.

Loss of verticality detection (man-down)

The phone detects an abnormal or tilted position that could indicate a fall or medical emergency.

This function is widely used in:

• manufacturing;
• construction;
• technical maintenance.

Example: an electrician collapses following a cardiac event in a technical room. The device detects the abnormal horizontal position and triggers an alert within a few seconds.

Impact or severe fall detection

Some models have sensors capable of identifying a significant impact.

This function makes it possible to detect more quickly:

• a fall from a ladder;
• a construction site accident;
• a sudden medical emergency.

Example: a roofer slips from a roof and falls several feet. The accelerometer detects the sudden deceleration on impact and immediately sends an alert together with the GPS location.

Loss of network or connection

Some devices automatically raise an alert in the event of prolonged loss of network or GPS connectivity.

This is particularly important in remote or technical areas.

Example: an employee working in a basement loses network coverage for more than five minutes. The system automatically alerts the supervisor, who can send someone to check the situation.

"I'm OK" check-in

The employee must periodically confirm that they are safe through a check-in.

If confirmation is not received within the allotted time, an alert is triggered.

Example: a delivery driver making nighttime deliveries must confirm their presence every 30 minutes. At 2 a.m., they fail to respond to two consecutive reminders, so an alert is sent to the alarm monitoring center.

Once triggered, the alert follows a structured process involving several stages:

1. Who receives the alert?
Internal contacts (manager, security manager, or colleague on duty) or an APSAD P5-certified alarm monitoring center operating 24/7.

2. How is the alert transmitted?
The alert is transmitted via IP, which requires a Wi-Fi or 4G connection. Depending on the configuration selected, the phone can then automatically call a predefined list of contacts and send them a text message, or transmit the alert directly to the alarm monitoring center, which manages the response.

3. What information is transmitted?
The worker's identity, the type of alarm triggered, and their GPS location, together with the date and time.

4. How is the alert managed?
An attempt is made to establish voice contact with the worker, the situation is assessed, and emergency responders are contacted if necessary.

In practice, the speed of response can make all the difference when dealing with a serious accident.

What features should a good PTI phone have?

• Detection reliability: accurate sensors for inactivity and loss of verticality.
• Geolocation: accurate (GPS, A-GPS), fast, and effective, even in difficult environments, including indoors via Wi-Fi/Bluetooth where available. For companies requiring real-time tracking of lone workers, continuous lone worker geolocation is a particularly useful complement to PTI/DATI devices, helping emergency responders intervene more quickly in the event of an incident.
• Connectivity: multi-carrier support, 4G, good network coverage, and resilience to signal loss.
• Audio and communication: powerful microphone and speaker for clear two-way communication in an emergency.
• Battery life: long-lasting battery and low-battery alert.
• Ruggedness and durability: IP rating for protection against water and dust, as well as impact resistance.
• Ergonomics and simplicity: easy for workers to use, with accessible buttons.
• Integration: ability to connect to a monitoring platform or alarm monitoring center.
• Silent and discreet alerts: particularly useful in the event of an assault.
• Regular testing function: to ensure that the device is working correctly.
• Specific certifications: particularly ATEX certification where the working environment requires it.

The general duty to protect workers

Contrary to a common misconception, U.S. law does not explicitly require employers to provide a specific PTI phone to every lone worker.

However, the Occupational Safety and Health Act of 1970 requires employers to provide a workplace free from recognized hazards that are causing or are likely to cause death or serious physical harm. This is known as OSHA's General Duty Clause.

OSHA does not have one general standard specifically covering all situations in which an employee works alone. However, certain industries and work environments have specific requirements for lone workers. OSHA also recommends appropriate emergency procedures and communication systems depending on the situation.

These obligations are not limited to traditionally "high-risk" sectors. An office employee traveling alone, an on-call technician, or a social worker conducting home visits may all face lone-working risks.

Where lone working creates a recognized risk, employers should implement appropriate organizational, technical, and preventive measures. A PTI/DATI solution can provide an effective technical response where the risk assessment identifies the need for one.

Risk assessment: the essential starting point

Every approach should begin with a workplace risk assessment. Employers should identify situations in which workers may be working alone and assess the associated risks: falls, assault, medical emergencies, accidents involving dangerous equipment, and so on.

This assessment provides the basis for determining appropriate protective measures, including a PTI/DATI solution where necessary.

Information, training and maintenance

Providing the equipment alone is not enough. Employers must:

• Inform workers about the risks associated with lone working;
• Train users on how to operate the device and follow emergency procedures;
• Maintain equipment in working order through regular checks, updates, and replacement of defective batteries.

Consequences of non-compliance

U.S. workplace safety requirements place significant responsibilities on employers. If a serious recognized hazard exists and the employer fails to take reasonable steps to prevent or reduce it, OSHA may take enforcement action under the General Duty Clause. Depending on the circumstances, an employer may also face civil liability and other legal consequences.

This makes it essential to properly assess lone-working risks and implement appropriate protective measures.

Construction: working at height, isolated construction sites, and exposure to vehicles, machinery, and dangerous equipment. The risk of serious falls is particularly high.

Manufacturing / Industrial: night shifts, maintenance work in isolated areas, and noisy environments where a call for help may not be heard.

Maintenance: field technicians and network operators often working alone around equipment that may be live, pressurized, or otherwise hazardous.

Care Services / Healthcare: home health aides, nurses, and other professionals conducting visits alone, with a potential risk of assault in certain situations.

Logistics / Transportation: long-haul drivers, warehouse workers, and employees working alone on night shifts.

Security / Guarding: night patrols and monitoring of large sites. Silent alerting is particularly valuable in these situations.

Retail / Hospitality: opening or closing a store alone, or night reception staff working without colleagues nearby.

In all these situations, PTI does not replace existing safety procedures. It complements them and ensures that, in the event of human error or a sudden incident, the emergency response chain can be triggered automatically.

1. Assess your needs and risks

Before choosing a device, it is important to clarify the intended use. A few practical questions can provide the basis for the assessment:

• Is lone working occasional, regular, or permanent?
• Does the work take place indoors, outdoors, or both? Are there areas with no network coverage?
• Which risks are the priority: falls, assault, medical emergencies, or machinery-related accidents?
• Is the area classified as ATEX?
• Is the cellular network stable across the entire site?
• Is 24/7 alarm monitoring required, or is an alert to internal contacts sufficient?

The right device will always depend on the actual level of risk identified through these criteria.

2. Choose the right type of device

Three main categories of solutions are available, each suited to different risk levels and operational requirements.

The dedicated GSM DATI device is the preferred choice for high-risk sectors subject to strict safety and compliance requirements, such as manufacturing, construction, ATEX zones, and demanding environments involving impacts, dust, or moisture. Its rugged hardware, independent battery, and safety-focused design make it the reference solution where failure is not an option.

The smartphone with a native PTI application offers a good compromise for workers with moderate mobility requirements who nevertheless need a high level of reliability: mobile technicians, maintenance staff, on-call teams, and professional services. Because the application is integrated into the firmware and cannot be uninstalled, it provides a high level of operational reliability while retaining the functionality of a conventional smartphone.

The PTI application downloaded onto a personal smartphone should only be considered for lower-risk situations and where the employer implements a rigorous monitoring procedure, including regular checks that the system is working correctly, training, and control procedures. This remains the solution most exposed to technical or human failure.

When in doubt, it is better to overestimate the level of risk than underestimate it: the cost of an inadequate solution following an accident can be vastly greater than the price difference between the available options.

3. Check the actual conditions of use

Many PTI projects fail because testing is carried out in good conditions rather than in the actual working environment.

It is essential to test, under real-life conditions:

• network coverage;
• geolocation;
• battery life;
• alarm activation and transmission;
• ergonomics when used alongside personal protective equipment (PPE).

4. Choose the right alert solution

A 24/7 alarm monitoring center is recommended for workers who regularly work alone, high-risk situations, or companies without an internal team available to respond to alerts.

Alerts to internal contacts can be suitable for occasional situations or as a supplementary solution, provided that genuine availability and a rapid response can be guaranteed.

5. Calculate the total cost of ownership

The purchase price only represents part of the actual investment. To compare two solutions fairly, all costs over their lifetime should be considered:

• SIM and connectivity costs;
• alarm monitoring contract;
• maintenance;
• technical support;
• employee training;
• equipment replacement at the end of its service life.

These costs can vary significantly depending on the type of device, number of users, and level of service selected. This is why it is generally more relevant to request a tailored quote based on an analysis of your needs rather than relying on a generic price that does not take your specific circumstances into account.

In all cases, a device that is cheaper to purchase but lacks reliable after-sales support can quickly become more expensive than a fully integrated solution—particularly if a fault or failure occurs at a critical moment.

6. Check the supplier's reputation

Choosing the right partner is just as important as choosing the equipment itself. Questions to ask during a consultation include:

• How long has the supplier been working in lone worker protection?
• Does it have customer references in your industry?
• What level of technical support does it provide?
• Can it help your organization implement appropriate safety measures?

Ideally, the support provided should include:

• risk assessment;
• device configuration;
• employee training;
• maintenance;
• technical support;
• regulatory monitoring.

A site assessment can often identify risks that are not visible during a purely theoretical assessment.

Scutum Premium Services supports organizations of all sizes in deploying PTI/DATI solutions adapted to their operational requirements and working environments.

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Yes, a standard smartphone can be used as a PTI phone through a dedicated application installed on Android or iOS.

Advantages:

• Lower cost, as no additional device is required
• Familiarity: employees use a device they already know, making adoption easier
• Rapid deployment across a team or organization

Limitations compared with a dedicated DATI device:

• Lower ruggedness: a consumer smartphone is not designed to withstand impacts, dust, or moisture in demanding professional environments
• Limited battery life due to the combined personal and professional use of the device, unlike a DATI device whose battery is dedicated to the alert function
• Variable application reliability: a downloadable application can be uninstalled, disabled, deprived of the necessary permissions, or disrupted by a system update, unlike a native application integrated into the firmware or a dedicated DATI device

This solution therefore requires specific, reliable software and should generally be reserved for moderate-risk situations.

No, U.S. federal law does not explicitly require employers to use a specific phone or device designated as a PTI system.

However, employers have a legal duty under OSHA's General Duty Clause to protect workers from serious recognized hazards and to take reasonable steps to prevent or reduce those hazards. OSHA also notes that there is no general standard specifically governing all situations in which an employee works alone, although specific industries and situations may have additional requirements.

In practical terms, if a workplace risk assessment identifies a lone-working situation requiring additional protection, the employer should implement appropriate measures to enable an alert to be raised and assistance to be provided quickly in the event of an incident.

PTI (Protection du Travailleur Isolé – lone worker protection) is one of the most recognized and reliable technical solutions for addressing this need. Depending on the actual level of risk, other organizational measures, such as regular check-ins, the presence of another worker, or call procedures, may also be appropriate.

In practice, PTI remains strongly recommended where a significant risk has been identified, as it provides alerting and geolocation capabilities that manual procedures cannot match.

Prices vary considerably depending on several factors, including ruggedness, built-in features, any ATEX certification, and the monitoring method used (24/7 alarm monitoring or internal alerting).

Given this variability, there is no meaningful average price to quote. The cost depends entirely on your working environment, requirements, and desired level of service.

The best approach is to request a customized quote based on an assessment of your actual needs.

Potentially, yes. An employee working remotely, alone at home and without anyone nearby who could provide assistance quickly, may be considered to be in a lone-working situation depending on the circumstances and the outcome of the risk assessment.

The employer should therefore take this situation into account when assessing workplace risks. If the assessment confirms a significant level of isolation, several measures may be considered:

• a regular check-in system;
• a call procedure or contact protocol at defined intervals;
• a PTI device, such as an application installed on a company smartphone.

There is no universal answer: the specific risk assessment for each situation determines the most appropriate solution.

Not just any PTI phone. An ATEX zone (potentially explosive atmosphere) requires equipment specifically certified for use in such an environment.

Using a standard device in an ATEX zone could potentially create an ignition source and therefore pose a serious safety risk.

ATEX-certified PTI/DATI devices are available and have been specifically designed to meet these requirements.

For more information about solutions suitable for explosive environments, see our dedicated article on ATEX smartphones and DATI/PTI devices for explosive environments.