In the industrial sector, machine safety standards play a crucial role in safeguarding operators and maintenance personnel. The PN-EN ISO 14119:2014-03 standard, harmonized with the Machinery Directive 2006/42/EC, forms an essential part of this safety framework. This article aims to elucidate how and when to apply interlocking devices with guard locking and the significance of stopping time in the context of safety.
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What is an Interlocking Device?
An interlocking device is a mechanical or electromechanical device integrated with a machine guard, designed to prevent access to hazardous areas of a machine until safety conditions are met. Its primary purpose is to protect operators and maintenance staff from unintentional or dangerous contact with moving machine parts. Interlocking devices are engineered to minimize the possibility of bypassing their function and ensure compliance with safety standards like PN-EN ISO 14119:2014-03.
Interlocking devices play a pivotal role in mitigating risks associated with the automation of production processes.
Understanding the PN-EN ISO 14119:2014-03 Standard
The PN-EN ISO 14119:2014-03 standard outlines the requirements for interlocking devices associated with guards, aimed at preventing access to hazardous machine areas. Its goal is to minimize the risks associated with accessing such areas during machine operation.
- Objective of the standard: Ensure that interlocking devices are designed and installed to guarantee the safety of machine users.
- Scope of the standard: The standard covers all interlocking devices associated with guards used in industrial machines.
Key Aspects of the PN-EN ISO 14119:2014-03 Standard
This standard defines key terms and requirements for the design and installation of interlocking devices. These include:
- Types of interlocking devices:
- Type 1: Mechanical interlocking devices that do not require external power to operate. Examples include mechanical locks.
- Type 2: Electromechanical interlocking devices that operate with external power. Examples include electromagnetic locks.
- Design requirements: Interlocking devices must be designed to minimize the possibility of being bypassed. They should be placed in hard-to-reach locations or secured against tampering.
- Installation: Interlocking devices must be installed to ensure reliability and effectiveness. They should be regularly checked and maintained.
Selecting and Designing Interlocking Devices
When selecting interlocking devices, consider:
- Type of machine and its hazardous areas: Selection should be tailored to the machine’s specifics and potential hazards. Collaborating with a design office and engineering outsourcing can aid in choosing appropriate solutions.
- Type of interlocking devices: Type 1 for simple applications with low bypass risk, and Type 2 for advanced systems requiring higher security.
- Minimizing bypassing: Interlocking devices should be designed and installed to prevent easy circumvention. This may involve special security screws or concealed mechanisms.
When to Use Interlocking Devices with Guard Locking
Guard locking is necessary when:
- The machine has a long stopping time: In situations where the machine cannot stop immediately upon guard opening, guard locking ensures the guard remains closed until the machine fully stops.
- Risk of entering the hazardous area: If there is a possibility that an operator might enter the hazardous area before the machine fully stops, guard locking is essential to prevent accidents.
Guard locking is not required when:
- The machine stops immediately: For machines that stop immediately upon guard opening, guard locking is unnecessary.
- No risk of entering the hazardous area: If there is no risk of entering the hazardous area before the machine fully stops, guard locking is not required.
Interlocking Devices: Safe Speed and Stopping Time
The significance of stopping time in safety lies in determining how long it takes for a machine to stop after an interlocking device is activated.
- Measuring stopping time: Determining the time from the activation of an interlocking device to the complete stop of the machine. This measurement is crucial for risk assessment and selecting appropriate interlocking devices.
- Risk assessment: Considering possible emergency scenarios and appropriately selecting interlocking devices. Depending on the stopping time, different types of interlocking devices may be required.
PN-EN ISO 14119:2014-03 and the Machinery Directive
The PN-EN ISO 14119:2014-03 standard is harmonized with the Machinery Directive 2006/42/EC, meaning that compliance with its requirements equates to ensuring conformity with the Directive.
- Compliance documentation: Companies must document compliance with the standard as part of the conformity assessment process with the Machinery Directive. Technical documentation should include all necessary information regarding the selection, installation, and maintenance of interlocking devices.
- Audit and control: Regular reviews and audits can help maintain compliance. A safety audit conducted at the project stage can minimize the risk of non-compliance.
Practical Tips for Companies Applying the Standard
To effectively apply the PN-EN ISO 14119:2014-03 standard, companies should:
- Assess risk: Conduct a risk assessment related to accessing hazardous machine areas. Risk analysis according to PN-EN ISO 12100:2012 is essential for proper evaluation.
- Select appropriate devices: Choose interlocking devices according to the standard’s requirements. Devices should be tailored to the specifics of machines and types of hazards.
- Regular inspections: Perform regular inspections and maintenance of interlocking devices. These inspections should be documented and conducted according to the manufacturer’s recommendations.
- Collaborate with a design office: A design office can assist in decisions regarding the type of guards and locks best suited for specific applications.
- Strength calculations (FEM): The design office can also perform strength calculations to ensure that guards and locks meet the standard’s requirements.
- Project management: Smart project management should include a safety audit conducted by an external company to minimize the risk of non-compliance with the Machinery Directive.
- Engineering outsourcing: Utilize experienced engineers to ensure that interlocking devices are properly designed and installed.
Automation and Interlocking Devices
Production automation significantly enhances the efficiency and productivity of industrial processes, but it also introduces new risks associated with machine operation. A high degree of automation can lead to situations where operators and technicians are exposed to contact with moving machine parts. Interlocking devices play a crucial role in minimizing these risks. They ensure that access to hazardous areas is only possible when the machine is stopped and safe. In the context of production automation, it is particularly important that interlocking devices are integrated with machine control systems, such as SCADA and PLC programming, to ensure full compliance and operational safety. Utilizing the services of an industrial automation integrator and conducting safety audits at the project stage can significantly reduce risk and ensure compliance with standards and directives, such as the Machinery Directive 2006/42/EC.
Regular inspections and maintenance of interlocking devices are essential to ensure their reliability and compliance with standards.
Interlocking Devices and ATEX Standards
In the context of using interlocking devices in explosive environments, it is crucial that these devices also meet ATEX standards. The ATEX directive and standards pertain to equipment and protective systems intended for use in potentially explosive atmospheres. Interlocking devices used in such areas must be appropriately certified and meet stringent requirements to prevent sparking and other ignition sources.
- Selection of interlocking devices: In ATEX zones, use interlocking devices that have the appropriate ATEX certification.
- Installation requirements: Interlocking devices must be installed in a manner that minimizes explosion risk, considering the specific requirements of explosive zones.
- Maintenance and inspections: Regular inspections and maintenance of interlocking devices in ATEX zones are crucial for ensuring their reliability and safety.
The PN-EN ISO 14119:2014-03 standard is a cornerstone of machine safety, helping companies ensure the protection of operators and technicians. Adhering to its requirements and practically implementing interlocking devices significantly enhances safety levels in the industry.
FAQ: Interlocking Devices
An interlocking device is a mechanical or electromechanical device that prevents access to a machine’s hazardous area until safety conditions are met.
There are two main types: Type 1 (mechanical) and Type 2 (electromechanical) devices.
Interlocking devices with guard locking are necessary when a machine has a long stopping time and there is a risk of entering the hazardous area before the machine fully stops.
No, but interlocking devices are recommended for machines with hazardous areas that cannot stop immediately upon guard opening.
Interlocking devices must be installed to ensure their reliability and effectiveness, minimizing the possibility of being bypassed.
Yes, interlocking devices installed according to the PN-EN ISO 14119:2014-03 standard meet the requirements of the Machinery Directive 2006/42/EC.
Industrial automation can lead to risks associated with unintended contact with moving machine parts, making the use of interlocking devices crucial.
Yes, regular inspections and maintenance of interlocking devices are essential to ensure their proper functioning and compliance with standards.
Collaborating with a design office provides expert assistance in selecting suitable interlocking devices and guards, enhancing machine safety.
Yes, interlocking devices can also be installed in existing machines as part of adapting machines to minimum safety requirements.