ANSI B11.0

Safety of Machinery: General Requirements & Risk Assessment

This standard applies to new, modified, or rebuilt power-driven machines that are not portable by hand, used to shape and/or form metal or other materials by cutting, impact, pressure, electrical or other processing techniques, or a combination of these processes. This can be a single machine, a machine tool or a machine tool system(s).

Other industry sectors may benefit from applying this standard.  Where a machine-specific standard exists and the requirements of that standard conflict with the requirements in this standard, the requirements of the machine-specific standard shall apply.

ANSI B11.0 presents an excellent discussion of the elements and various techniques of risk assessment. It also does the following:

  • Presents a simple means of conducting risk assessment
  • Offers a good review and discussion of the Hierarchy of Control
  • Provides a reintroduction of the ISO 14121 list of Hazards that should be used by anyone conducting risk assessment

What is Considered Tolerable Risk?

In the discussion of risk reduction, the topic of tolerable risk is addressed. Any organization seriously considering risk assessment and trying to determine how to define tolerable risk should look at this document in detail. Tolerable risk gets a lot of discussion and many users don’t know where to start. Consider using this document to get good grounding in Risk Assessment.

Following are the B11.0 considerations for tolerable risk:

  • Risk-reduction benefit;
  • Technological feasibility;
  • Economic impact;
  • Ergonomic impact;
  • Productivity;
  • Durability and maintainability;
  • Usability.



ANSI B11.0-2020 specifies basic terminology, principles, and a methodology for achieving acceptable risk in machinery design and use. To help designers, integrators, and users of machinery achieve this objective, it specifies principles of risk assessment and risk reduction—these principles are supported by knowledge and experience in the design, use, incidents, accidents, and risks associated with machinery.

If you have further questions regarding ANSI B11.0, contact us today for help.