BS EN ISO 13851:2019

What is ISO 13851- Two-hand control devices (THCD)design and selection principles about?

ISO 13851 discusses safety regarding two-hand control devices (THCD). ISO 13851 is an international safety standard that provides for the safety requirements and design and selection of two-hand control devices.

ISO 13851 is a generic safety standard (type-B2) that specifies the safety requirements of a THCD and the dependency of the output signal from the actuation by the hand of the control actuating devices.

ISO 13851 details the main characteristics of THCDs for the achievement of safety and sets out combinations of functional characteristics for all three types of standards (type A, B, C).

ISO 13851 provides requirements for design and guidance on the selection (based on a risk assessment) of THCDs including the prevention of defeat, the avoidance of faults, and verification of compliance.

ISO 13851 applies to all THCDs, independent of the energy used including:

• THCDs which are fully assembled for installation
• THCDs which are assembled by the machine manufacturer or integrator

Note 1: ISO 13851 does not apply to devices intended to be used as enabling devices, as hold-to-run devices, or as special control devices.

Note 2: ISO 13851 does not specify which types of the two-hand-control device shall be used for a specific application and while guidance is given, it does not specify the required distance between the THCD and the danger zone.

Note 3: Under ISO 13851 a THCD only offers protection for the person using it.

Note 4: For specific machines, the suitability of a two-hand control as a suitable protective device can be defined in a type-C standard. If such a standard does not exist or is not appropriate, the risk assessment and determination of suitable protective measures is the responsibility of the manufacturer of the machine.

Who is ISO 13851- THCD design and selection principles for?

ISO 13851 on principles and design of two-hand control device is applicable to:

Stakeholder groups representing the market players about machinery safety

• Machine manufacturers (small, medium, and large enterprises)
• Health and safety bodies (regulators, market surveillance, etc.)

Others can be affected by the level of machinery safety

• Machine employers (small, medium, and large enterprises)
• Machine employees (e.g., trade unions)
• Service providers like for maintenance (small, medium, and large enterprises)

Why should you use ISO 13851- THCD design and selection principles?

A two-hand control device (THCD) is a protective device that protects against reaching danger zones during hazardous situations by locating the control actuating devices in a specific position and distance from the danger zone.

ISO 13851 assists in selecting an appropriate THCD based on risk assessment and provides for prevention of defeat, the avoidance of faults, and verification of compliance of THCD.

ISO 13851 provides an appropriate design for THCD to build an effective product that is sustainable for the long-term business needs of the product.

ISO 13851 assists in enhancing the safety of THCDs by providing recommendations and safety requirements for THCD.

By adopting ISO 13851 you can enhance the safety of THCD and build a product that is fine-tuned to do consistently well in the marketplace.

What’s changed since the last update?

BS EN ISO 13851:2019 supersedes EN 574:1996+A1:2008, which is withdrawn.