Laser Scanning in ATEX Areas: What You Need to Consider

Laser scanning of ATEX areas is one of the most demanding measurement tasks in the process industry. Hazardous explosive environments set boundary conditions for a project that must be understood before a single scanner is brought onto a site. When these boundary conditions are properly managed, laser scanning in Ex zones produces accurate and usable documentation safely and efficiently.

This article walks through, at a practical level, what needs to be considered when laser scanning ATEX areas: the impact of classification on equipment selection, work planning requirements, the benefits of measurement, and the most common mistakes that slow down or jeopardize a project.

What ATEX classification means for laser scanning in practice

The ATEX directive divides explosive atmospheres into zones based on how frequently and for how long an explosive mixture is present. Zones 0, 1, and 2 are used for gaseous substances, and zones 20, 21, and 22 for dusts. The lower the number, the stricter the requirements for equipment brought into that area.

From a laser scanning perspective, the classification determines everything: which device you are permitted to bring in, who needs to be present, and what permit procedures the project requires. A scanner used in Zone 1 or 21 must be Ex-certified for that zone. In Zone 2 or 22, requirements are somewhat less stringent, but still significantly stricter than in a standard industrial environment.

In practice, this means that the starting point for project planning is always the facility’s ATEX zone map. Before measurement work begins, it must be established which areas fall under which zone and whether zone boundaries have changed since the last documentation.

Equipment and certification requirements in Ex zones

A laser scanner brought into an Ex zone must meet the ATEX directive’s equipment category requirements for the zone in which measurements are taken. Certification is not an optional extra but an absolute prerequisite. This applies not only to the scanner but to all other electrical devices brought along: batteries, data transfer devices, and lighting.

Today, Ex-certified mobile laser scanners are available on the market that are suited to demanding industrial environments. The advantage of mobile laser scanning over fixed-station scanning methods is measurement speed: it covers significantly more square meters per day, which is especially valuable at facilities where access to Ex areas is time-limited or requires a constant escort.

In addition to equipment certification, measurement personnel must hold appropriate safety training related to Ex zones. Many facilities also require site-specific inductions before access to the measurement area is granted. These requirements should be clarified already at the tender stage so they can be factored into the project schedule.

Work planning and safety practices before scanning

Thorough work planning is more important in laser scanning of ATEX areas than in any other measurement project. Permit and risk assessment processes take time and must be initiated well in advance of the measurement day.

Typical advance preparation includes the following steps:

• Reviewing the ATEX zone map and zone boundaries with the facility’s safety officer
• Initiating the written permit-to-work process in accordance with the facility’s procedures
• Conducting a risk assessment for the measurement area, including any potential process changes during measurement
• Submitting equipment certification documents to the facility in advance
• Clarifying emergency procedures and evacuation routes before work begins

During measurement, it must be clearly agreed who is responsible for monitoring process conditions and under what circumstances measurement work is to be halted. If process conditions change during measurement, it is better to stop and resume later than to continue in an uncertain situation.

Benefits of laser scanning in process industry Ex zones

Documenting a hazardous area by laser scanning significantly reduces the need for repeated site visits. Once an accurate point cloud has been produced, designers, maintenance teams, and equipment suppliers can carry out a large part of their work remotely without needing to access the Ex area themselves.

This is particularly valuable in shutdown planning. When pipework, equipment, and structures have been documented to millimeter accuracy before a shutdown, lifting plans, installation sequences, and clash checks can be carried out in advance. The number of surprises on site is reduced, and shutdown time is shortened.

In Ex zones, laser scanning also improves safety during the planning phase. When the source data reflects reality rather than outdated design documents, errors that would otherwise only be discovered during installation work are avoided. This is especially relevant for older facilities whose original drawings no longer accurately represent the as-built condition.

In process industry sectors such as the energy industry and the mining industry, where Ex areas are often extensive, combining laser scanning data with the Reality Twin service enables information to be accessed on a location basis throughout the facility’s entire lifecycle without repeated site inspections.

Most common mistakes in ATEX area measurement projects

Based on experience, the majority of problems in ATEX area laser scanning projects stem from inadequate advance preparation rather than from the measurement work itself.

The most common mistakes are:

• Failing to verify equipment certification: A missing Ex certification discovered on the day of measurement brings the entire project to a halt. Certificates must be checked and submitted to the facility in advance.
• Assuming the ATEX zone map based on outdated documents: Zones change as processes are modified. The current zone map should always be confirmed with the facility’s own safety organization.
• Underestimating the permit process: The permit-to-work procedure can take several days. If it is initiated too late, the measurement day will be delayed.
• Inadequate personnel induction: Safety training related to Ex zones and site-specific induction must be completed before measurement, not on the morning of it.
• Unclear measurement scope: If it has not been clearly agreed in advance which areas are to be measured and to what level of detail, situations easily arise where part of an important area is left unmeasured.

These mistakes are best avoided when the measurement project has a clearly designated responsible person on both the client’s and the service provider’s side, and when project preparation is started early enough. Laser scanning of ATEX areas is a demanding task, but when properly planned, it produces documentation that serves the facility for decades to come.