NR-12 for robot cells: Brazil's machinery safety rules

NR-12, Brazil's regulation on safety at work in machinery and equipment, devotes a single item to robot systems: 12.1.12. Elsewhere, robots appear only in passing, in the glossary and as a feeding method for presses in Annex VIII. The item is short, and it answers the question every project asks: which technical standards a robot cell must follow to be compliant. The rest of the regulation still applies in full, from safety systems to manuals and training.

This article goes through the items that weigh most in a cell with an industrial robot, using the numbering of the official text published by the Brazilian Ministry of Labour and Employment. It is informative: it does not replace reading the regulation or the risk assessment of your cell.

What NR-12 says about robots

Item 12.1.12 reads as follows (unofficial translation; the official text is in Portuguese):

Robot systems that comply with the provisions of standards ABNT ISO 10218-1, ABNT ISO 10218-2, ISO/TS 15066 and other official technical standards or, in their absence or omission, applicable international standards, are in conformity with the safety requirements set out in this regulation.

Each standard cited has an addressee:

ISO 10218-1 covers the robot itself and is addressed to the manufacturer.
ISO 10218-2 covers the application and the cell, and is addressed to whoever integrates.
ISO/TS 15066 covers collaborative applications.

ISO published new editions of both parts in 2025, replacing those of 2011. Part 2 is now titled "Industrial robot applications and robot cells", incorporates most of the requirements for collaborative applications that were in ISO/TS 15066, and adds cybersecurity requirements related to robot safety.

For machines already installed, item 12.1.9.2 waives compliance with requirements from standards published after manufacture, import or retrofit, provided the machine meets NR-12 and the standards in force at that time. For a new project, the path is to work with the edition in force. It is worth checking in the ABNT catalogue which Brazilian edition is valid at the date of the project.

The basis of everything: risk assessment

Item 12.1.9 states that, in applying the regulation, the characteristics of the machine and the process, the risk assessment and the state of the art must be considered. The glossary defines risk assessment as the complete process comprising risk analysis and risk evaluation, with reference to ABNT NBR ISO 12100.

In a robot cell, this means examining each task, not only automatic production: loading and unloading, tool change, program adjustment, cleaning, clearing jams and maintenance. The safeguards come out of that analysis, not from a ready-made template.

The order of priority of the measures is in item 12.1.8: collective protection, then administrative or work organization measures, then personal protection.

The items that weigh most in a robot cell

Item	What the regulation requires	How it appears in the cell
12.5.1	Hazard zones with fixed guards, movable guards and interlocked safety devices	Perimeter enclosure, doors, light curtains, scanners
12.5.2	Safety category according to the risk assessment, technical responsibility of a legally qualified professional, installation that makes defeating difficult	Safety design stating the category or performance level of each function
12.5.6	Movable guard when access is required more than once per shift, with guard locking when opening allows access before the hazard has ceased	Loading door that only unlocks with the robot stopped
12.5.3 and 12.5.13.1	Manual reset when indicated by the risk assessment, with the actuator placed for a full view of the protected zone	Reset button outside the cell, from where the whole interior is visible
12.5.13.3	Emergency stop inside the protected zone and means of releasing trapped persons	Internal button and opening from the inside
12.6	Accessible emergency stop that overrides all other commands	Buttons on the cabinet, on the teach pendant and at the stations
Annex I	Minimum distance for light curtains: S = (K x T) + C	Curtain positioned by calculation, not by leftover space
12.11.3	Interventions with the machine stopped, with isolation and lockout of energy sources	Lockout and tagout procedure
12.13	Manual in Brazilian Portuguese, supplied by the manufacturer or importer	Robot and cell documentation in Portuguese
12.16	Training before the worker takes up the role	Operation, programming and maintenance training

Three of these points deserve detail.

Safety category and qualified professional

The NR-12 glossary defines category as the classification of the safety-related parts of a control system with respect to their resistance to faults, in five levels (B, 1, 2, 3 and 4), according to ABNT NBR 14153. Item 12.1.11 also recognizes machines built in accordance with NBR ISO 13849, parts 1 and 2, which works with performance levels.

Item 12.5.2 requires safety systems to be under the technical responsibility of a legally qualified professional. In engineering, that responsibility is registered through the Technical Responsibility Annotation (ART), established by Law No. 6,496/1977. And, depending on the risk, item 12.5.17 states that a design, diagram or schematic representation of the safety systems, with specifications in Portuguese, may be required.

Light curtain distance

In the Annex I formula, S is the minimum distance between the hazard zone and the detection plane, K is the approach speed of the body, T is the overall stopping time of the system and C is an additional distance linked to the detection capability of the curtain. For vertical curtains, the annex adopts 2,000 mm/s when the distance results in up to 500 mm, and allows 1,600 mm/s above that.

The practical consequence is direct: the longer the robot takes to stop, with the real load and speed, the farther away the curtain has to be. That is why curtain position is a design result, not a layout convenience.

Programming and maintenance inside the cell

When it is not possible to intervene with the machine stopped and locked out, item 12.11.3.1 requires an operating mode that disables automatic control and allows the work with a hold-to-run control device combined with reduced speed. This is the logic of the manual mode of robots, in which the programmer controls the arm directly with an enabling device in hand. ISO 10218-1 defines the reduced-speed safety function as a limit of no more than 250 mm/s.

Who is responsible for what

Robot manufacturer. Delivers the robot in accordance with ISO 10218-1, with documented safety functions. For the standard, the robot alone is partly completed machinery.
Integrator. Is responsible for the application and the cell, the subject of ISO 10218-2: risk assessment of the application, design of the safety systems, validation and information for use. The role is detailed in the article on the robot integrator.
Employer. Must adopt protective measures for work on machines (12.1.7), keep maintenance records (12.11), prepare work and safety procedures based on the risk assessment (12.14) and train workers (12.16).

Imported robots

Item 12.15.2 prohibits the manufacture, import, sale, rental and transfer of machines that do not meet the regulation. And item 12.13 requires a manual in Brazilian Portuguese, supplied by the manufacturer or the importer, with safety information for all phases of use.

In practice, the robot arrives as partly completed machinery, and the cell is designed and validated in Brazil. Compliance is built locally, by whoever integrates, with the documentation the regulation asks for.

Collaborative applications also go through the regulation

The 2025 edition of ISO 10218 stopped using the term collaborative robot and started referring to collaborative application, because only the actual application can be developed, verified and validated as collaborative. The risk assessment considers robot, tool, part and task. A force-limited robot carrying a part with a sharp edge is still a hazard to be addressed.

The differences between the two approaches are in collaborative robot vs industrial robot.

Points of attention in robot cells

Light curtain installed without the Annex I calculation.
Reset without a full view of the protected zone. For that case, item 12.5.13.2 calls for presence sensing or a system that forces the person to go to the zone that cannot be seen, such as a double reset.
Door with a simple interlock where the stopping time calls for guard locking (12.5.6).
Interlock that is easy to defeat (12.5.2, item d).
Safeguards treated as an optional line of the proposal. Item 12.5.16 states that guards, devices and safety systems are integral parts of the machine.
Training only for those who operate. Items 12.16.1 and 12.16.2 cover operation, maintenance, inspection and other interventions.
Generic risk assessment, without the real tasks of the cell.

What to ask for together with the cell

Risk assessment of the application, with the tasks considered.
Design or diagram of the safety systems, in Portuguese.
Category or performance level of each safety function.
Calculation record of the safety distances.
Robot and cell manuals in Portuguese.
Training plan for operation, programming and maintenance.
Record of technical responsibility.

These items apply to any application, from the robotic welding cell to the cell with a palletizing robot, and they are part of the real project cost, as shown in industrial robot cost.

Frequently asked questions

Does NR-12 apply to industrial robots?

Yes. A robot cell is a machine for the purposes of the regulation. Item 12.1.12 considers compliant the robot systems that follow ISO 10218-1, ISO 10218-2, ISO/TS 15066 and the other applicable official technical standards.

Does every robot cell in Brazil need a fence?

The regulation requires hazard zones to have safety systems, which may be fixed guards, movable guards and interlocked safety devices. The combination of fencing, interlocked doors, light curtains and scanners comes out of the risk assessment of each cell.

Does a collaborative robot have to comply with NR-12?

It does. ISO/TS 15066, cited in item 12.1.12, deals precisely with collaborative applications. The risk assessment considers the whole: robot, tool, part and task. A sharp tool or a heavy part may require safeguards even with a robot designed for collaboration.

Who is responsible for the safety of a robot cell?

The manufacturer is responsible for the robot, the integrator for the application and the cell, and the employer for protective measures, maintenance and training. NR-12 requires safety systems to be under the technical responsibility of a legally qualified professional.

Where should the light curtain be placed in a robot cell?

At the minimum distance calculated with the formula in Annex I of NR-12, S = (K x T) + C, based on ISO 13855. The result depends on the overall stopping time of the system and on the detection capability of the curtain, not on the space available in the layout.

Talk to BR Robotics

BR Robotics integrates QJAR robots in Brazil, from cell design to start-up. Bring these questions to the conversation with BR Robotics, together with the process, the part and the target cycle time. Talk to BR Robotics or see the robot line.