What Is a Hazard? Identifying Sources of Harm in Robotics.

What Is a Hazard?

A hazard is a source, situation, or condition with the potential to cause harm.

In robotics and industrial automation, hazards can arise from moving machinery, electricity, heat, sharp tools, heavy loads, pressure, and other sources.

For example, a robotic arm carrying a heavy metal component may create a crushing hazard if a person can become trapped between the moving arm and nearby equipment.

Identifying hazards is an essential step in designing and operating machinery safely.

Key Takeaways

• A hazard is something capable of causing harm, even if no injury has occurred.
• Robots can present mechanical, electrical, thermal, and other hazards.
• Identifying a hazard is different from evaluating the likelihood and severity of harm associated with it.

What Are Common Hazards in Robotics?

Several categories are particularly important.

Mechanical hazards: Crushing, shearing, entanglement, impacts, and unexpected movement.

Electrical hazards: Electric shock, short circuits, and other electrical failures.

Thermal hazards: Burns or other harm from hot components and processes.

Stored-energy hazards: Movement caused by pressurized systems, springs, gravity, or other stored energy.

Tooling hazards: Sharp tools, welding equipment, cutting devices, or hazardous materials.

A robot may present several hazards simultaneously.

Hazard vs. Risk

The terms are related but not interchangeable.

A hazard is the potential source of harm.

Risk concerns the likelihood and severity of harm under particular conditions.

Consider a robot carrying a heavy payload.

The payload presents a potential crushing hazard.

The level of risk depends on factors such as whether people can enter the area, how the robot moves, what safeguards are installed, and how the equipment is used.

The same hazard can therefore present different levels of risk in different operating situations.

Why Does Hazard Identification Matter?

Hazards must be identified before suitable protective measures can be selected.

For example, a factory may install a collaborative robot intended to work near employees.

Even if the robot has built-in force-limiting features, the tool attached to it could present a sharp-edge hazard.

A complete evaluation considers the robot, tool, workpiece, surrounding machinery, and expected human activities.

The collaborative designation does not eliminate the need for hazard identification.

Can Hazards Be Eliminated?

Some hazards can be eliminated through design changes.

Others can be reduced through engineering controls, protective devices, and operating procedures.

For example, removing an unnecessary sharp edge can eliminate a particular cutting hazard.

A protective enclosure can reduce exposure to a moving mechanism.

The appropriate measures depend on the application and relevant safety requirements.

Frequently Asked Questions

Is a hazard the same as an accident?

No. A hazard has the potential to cause harm. An accident is an event that may result in injury or damage.

Can a robot be hazardous while powered off?

Yes. Suspended loads, stored energy, sharp tools, and other conditions can remain hazardous without electrical power.

The Bottom Line

Hazards are potential sources of harm that must be considered throughout a robot's design and operation. Recognizing them is the starting point for assessing and reducing risk.