What is ISO 3691-4?
ISO 3691-4 is an international standard that specifies safety guidelines for "driverless industrial trucks".
Most mobile robots, including Automated Guided Vehicles (AGVs), Autonomous Mobile Robots (AMRs), Automated Guided Carts (AGCs) and others fall under this standard.
Key Components of ISO 3691-4
ISO 3691-4:2023 has six major sections, five annexes and spans 82 pages. The first three sections are introductory (Scope, Normative references, and Terms and definitions). The real "meat and potatoes" are in sections 4, 5, and 6:
4. Safety Requirements and/or protective/risk reduction measures
This section describes how to design a robot for safe operation. The description includes both hardware design and operational (software) design requirements.
For example, this section contains stipulations against sharp edges and ground clearance that could result in someone's foot becoming trapped under the robot. This same section also covers obstacle detection and avoidance, safety bumper design, E-Stop placement, and more. There's a lot going on here.
This is probably the single most important section to ISO 3691-4 for someone to read since it contains all the actual safety guidelines.
5. Verification of the safety requirements and/or protective/risk reduction measures
This section describes how to test the design requirements outlined in the previous section. I presume this section is mostly written for OEMS and their third-party ISO 3691-4 auditors, but if you doubt the safety of one of your robots, this section will tell you how to set up a test to test your concerns.
The tests described in this section are very specific. For example, here's the diagram showing how to validate obstacle detection, or as they call it, the "Test for the Detection of Persons".
6. Information for use
This section describes the contents of the instruction manual that must come with the robot. Highlights include:
- PPE required for operation of the robot (if any)
- Basic robot information - make, model, description, etc.
- Max speed/slope/capacity/etc.
- Intended operation, safety guidelines, and risk mitigation for same
- Required environmental conditions
- And much, much more
This section is quite thorough so if you've received a thin/light manual from your robot OEM, definitely use this to hold them accountable.
What's NOT in ISO 3691-4?
There's A LOT covered in this document, but ISO has published over 25,000 standards, and many of those are adjacent or even overlap with 3691-4.
For example, ISO 13850 is all about the Emergency stop - how buttons should be designed and actuated, where they should be placed, and more.
There is also list of hazards you might face with mobile robots depending on your specific application that are NOT covered in ISO 3691-4:
- Noise
- Vibration
- Various types of radiation
- Operation in explosive environments
- Operation on public roads
- Operation in military environments
- Operation while carrying hazardous loads (molten metals, acids/bases, etc)
- Trailers being towed behind the truck
- And the list goes on.
In other words, ISO 3691-4 is quite comprehensive, but does not account for every possible use case of a "driverless industrial truck". If you're responsible for robot deployment, you should read the whole standard at least once so you at least know where to go for more information to ensure a safe deployment.
Who Should Learn ISO 3691-4?
Honestly, everyone who works with mobile robots should be familiar with industry safety standards.
Having a 'single source of truth' for robot safety - like an international standard - allows all parties in a robot deployment to use common terminology and deployment standards, which increases deployment speed.
ISO 3691-4 for Operators
Operators - companies buying mobile robots - are at the top of the list. Since these companies are buying the equipment and deploying alongside their workers, it's critical for companies to have staff read, understand, and follow this standard or one like it.
This will greatly improve the deployment safely, even if you hire an outside party to do most of the heavy lifting. By having your own staff trained safe robot design, implementation, and operation you'll keep your workplace safe and greatly mitigate robotic accidents.
ISO 3691-4 is not exactly "fun" reading material, but at 82 pages, it can easily be read in a day. It's also very well-organized so you can keep it around to use as reference/reminder material for your team whenever robots projects are being considered.
ISO 3691-4 for System Integrators
Even a robot with an excellent safety-centric design can be deployed in an unsafe manner. For that reason, it's very important for robotic distributors, system integrators, and other third party installers to have a firm understanding of robot safety standards - what they are and how to remain compliant with them.
Additionally, if a customer wants to manage their own robot fleet after the initial deployment, it's exceedingly important for system integrators to be able to provide knowledge transfer to that company that includes both safety guidelines and where to go if the customer has more questions about how to run the fleet safely.
ISO 3691-4 for OEMs
Objective third-party safety standards take most of the guesswork out of determining whether a solution is safe or not. An objective body like ISO sets the standards, and OEMs serious about safety hire third parties to audit their compliance with those standards.
If you are considering a new robot purchase, ask about their safety compliance!
By following recognized standards like ISO 3691-4:2023, robot manufacturers can design safe operation into the very heart of their robots before they even leave the drawing board.
Additionally, building standards-based compliance into their robot design will ensure their customers receive a solution that remains safe while meeting their production and financial goals.
Is ISO 3691-4 Compliance Legally Required?
Yes and no. ISO is an international standards body and has no enforcement arm. They won't drag you to court if you fail to meet their standards.
That said, your local government might prosecute you for failing to meet ISO 3691-4 or a standard like it. This happens one of two ways in North America.
In the United States, OSHA is mostly reactive, meaning they typlically only investigate serious injuries or anonymous tips. If they are called because someone was hurt by a robot, they will look to assign fault for the accident. Buying, deploying, and operating robots in compliance with a known standard like ISO 3691-4 is a good start towards demonstrate your company's commitment to safe operating standards and risk mitigation.
The Canadian province of Ontario, however, is proactive in its approach to safety. Companies must perform a pre-start health and safety review before implementing new equipment or processes. During this review, employers have an outside firm review proposed solutions and make recommendations about how to deploy it safetly, including any modifications that might need to be made for safe operation. If you can't make the solution safe, you can't even deploy it.
Where do I get ISO 3691-4?
Right now there are only two official sources for ISO standards:
- The ANSI Webstore (PDF Format)
- Amazon (Paperback)
You might be able to find the document online somewhere, but we don't endorse copyright violations!
Thouzer AGV: A Model of Safety and Compliance
If you're looking for a simple way to improve or automate your material handling efficiency, while staying safe at the same time, take a look at the Thouzer AGV. Thouzer was designed against ISO 3691-4 with safety in mind.
Thouzer's engineers meticulously followed the ISO recommendations to ensure that every aspect of the Thouzer AGV, from its structural design to its control systems, meets the highest safety standards.
Key safety features of Thouzer AGV include robust obstacle detection systems, reliable emergency stop functions, and user-friendly interfaces that facilitate safe interaction with human operators. Regular maintenance protocols and comprehensive training programs further ensure that the AGVs operate safely throughout their lifecycle.
By prioritizing compliance with ISO 3691-4, Thouzer AGV not only guarantees a safe working environment but also exemplifies our commitment to innovation, thoughtfulness, and support for our customers.
Learn More About Thouzer
Want to learn how Thouzer AGV can safely automate your material handling processes while providing a killer ROI?
You can easily download ISO 3691-4 from the ANSI web store. At this article's publication, the standard was $200 for ANSI members and $250 for non-members.
It depends. ISO 3691-4 is a set of industry best practices published by an international non-profit organization. ISO has no enforcement arm to chase you down and prosecute you if you fail to comply with their standards; however, consider these points:
- The United States often review safety incidents retroactively. For example,
At the time of this article's publication, ISO 3691-4 was roughly four years old. It's worth mentioning that the standard was also just updated just last year (ISO 3691-4:2023).
ISO, The International Organization for Standardization, is a worldwide federation of national standards bodies. ISO strives to gather industry best practices from around the world and publish these best practices as guidelines for voluntary compliance. They do not have an enforcement arm. Currently there are 172 member nations in ISO.
According to the 3691-4 foreword, the new version includes:
- A list of significant hazards not covered by this standard's Scope
- Updated references to current versions of other relevant documents/standards
- Additional requirements for vehicles with drivers/riders
- Definition of "active detection field" and "operational stop"
- Multiple other updates across several sections