Many new CNC machines offer state-of-the-art safety features, but unfortunate accidents occur when operators deviate from the equipment manufacturer’s guidelines. These incidents can happen when workers become distracted, try to speed up a process, or inappropriately modify a tool. Even the most experienced CNC machine operators can become seriously injured in an accident when not following the proper protocols.

Preventing injuries and maintaining a safe workplace includes understanding potential CNC machine hazards, providing your employees with the necessary equipment training, and establishing a mandatory company-wide safety program.

Hazards Associated With CNC Machines

The most common types of CNC machine hazards involve the dangers of coming in contact with a moving part of the equipment. Any moving part on a CNC machine can cause injury if operators do not follow the appropriate machine protocols.

Single rotating parts — such as couplings or shafts — can pose snagging or entanglement risks. Two or more parts turning together — like pulleys, rollers, or gears — can cause point or pinch hazards. Other components like robotic arms or sliding mills can cause dangers involving shearing or crushing. Grinders and parts that can fragment or rupture can potentially result in an impact injury.

Although not classified as mechanical dangers, multiple health hazards correlate with CNC machinery, including using chemicals or solvents that damage the skin or eyes. Workers also face risks from other harmful elements around a shop, like metal particles, dust, fumes, heat, and excessive noise. Dealing with these hazards requires thorough employee training and implementing procedures that enforce the proper use of personal protective equipment (PPE).

Safety managers must implement strict guidelines surrounding minimum distances between machines and the required footwear to prevent slips and falls that could lead to severe injuries. In addition, maintenance personnel should perform regular checks on a shop’s electrical system to help avoid shock-related accidents.

Health and Safety Regulations for CNC Machines

The Occupational Safety and Health Administration (OSHA) requires that workplaces and equipment have the necessary safeguards to protect workers from preventable harm like burns to the skin, crushed fingers or hands, and eye injuries. Any equipment part, process, or function that can potentially cause an injury must have these protective features. The regulations also state that employers must eliminate or control the hazards when an operator or other worker becomes injured.

OSHA Standard 1910.212(a)(1) defines the types of acceptable guarding methods for CNC equipment.

Common Safety Devices Included With CNC Machines

Most new CNC machines come with various safety features to ensure accident-free operation. Machine operators must make sure these devices are in place and activated when using the equipment. Examples of these devices include:

• Emergency stop buttons: Emergency stop switches typically link to the machine’s control system or circuit breaker. They enable workers to shut down the equipment instantly during operation. This feature is usually present in several locations, including the control panel and the handheld unit.
• Soundproof casings: These noise enclosures lessen the noise a machine produces during operation. They consist of sound-absorbing materials and high-density noise barriers that block, dampen, and absorb sound waves. These casings can also help protect the operator from flying objects or part fragments.
• Guard fences: A guard fence establishes the maximum work area of the machine and protects the operator from moving equipment parts and flying objects. These fences also prevent unauthorized access during operation.
• Curtain guards: Many curtain guard designs allow for flow-through ventilation and visibility when a CNC machine is running. The guards can also capture debris while blocking fingers and hands from entering the guarded area.
• Contact mats: Operators place contact mats around CNC machines to prevent unauthorized or unsafe access to specific points inside the work area. These devices are pressure-sensitive, immediately stopping the machine when activated.

5 Recommended Precautions for CNC Machine Safety

Here are five essential machine shop safety tips when operating CNC equipment.

1. Use the Proper PPE

Personal protective equipment is one of the foundations of establishing a proactive safety program for any machine shop. Even though a machine may have functioning guards or fences, PPE offers a secondary level of protection and is especially effective after a part finishes machining.

Examples of PPE include:

• Eye protection
• Hearing protection
• Face shields
• Hand protection
• Approved footwear

Operators should also contain long hair and avoid loose-fitting clothing. Some workplaces may require other types of specialized protection, like respirators or aprons.

2. Follow Machine Instructions for Safe Operation

Many new CNC machine models include safety interlocks that prevent doors from opening while tools are moving. However, some older units may not offer these features. Operators should always ensure the safety fences and guards are in place while operating the machinery, specifically ensuring that the doors remain closed. Under no circumstances should an operator place a body part inside the machine or near the spindle when it’s running or during power-up mode.

In addition, safety managers should consider posting signs that warn about potential equipment hazards. Most machine manuals offer specific guidelines promoting operator safety.

3. Do Not Modify Tools or Machines

Altering CNC machines to perform in ways outside of their intended functions can be extremely dangerous. All operation manuals for CNC equipment warn against modifying tooling or operating outside the programmatic functions. If hardened steel tooling collides with other equipment components, it can release enormous amounts of energy, causing tools to break through enclosures and presenting a safety risk.

Never attempt to avoid purchasing a new tool by modifying an existing one to do a job. In addition, only qualified technicians or maintenance personnel should perform necessary repairs.

4. Keep Workspaces, Machines, and Tools Clean and Well-Maintained

Improperly maintained equipment can pose potential health risks to workers. Operators should clean the machines and tools between tasks to prevent dirt, debris, and other substances from building up and causing damage. Maintaining a clean and uncluttered work environment around your workstation and machine shop can prevent non-mechanical injuries, such as slips, trips, and falls.

In addition to protecting and extending the life of your equipment and tools, routine cleaning and maintenance can produce higher-quality parts.

5. Establish an Emergency Action Plan

Ensuring trained employees are available to handle emergencies at your shop can save lives. An employee who knows first aid and CPR should be part of every department in your facility. Safety managers should also establish protocols to handle chemical spills, fires, and other emergencies.

Contact KAAST Machine Tools to Learn More

At KAAST Machine Tools, we understand the importance of machine safety and implementing the most effective practices across your facility. Since 2010, we have supplied easy-to-use CNC machines and chip-making equipment to customers across the United States and around the world. If you’re interested in learning more about the safety guidelines we recommend for our machinery, our knowledgeable and experienced team can assist you.

Connect with us online or call 610-441-7317 to request a quote on any of our machine models.