Residual Risk; Machine Safety In The Usa; Minimum Requirements Of The Osha - Siemens SINUMERIK 840D sl Function Manual

1050). Annex A of the standard describes a method for determining the required Safety
Integrity Level (SIL).
Regardless of which standard is applied, steps must be taken to ensure that all the machine
controller components required for executing the safety-related functions fulfill these
requirements.
2.2.11

Residual risk

In today's technologically advanced world, the concept of safety is relative. The ability to ensure
safety to the extent that risk is ruled out in all circumstances – "zero-risk guarantee" – is
practically impossible. The residual risk is the risk that remains once all the relevant protective
measures have been implemented in accordance with the latest state of the art.
Residual risks must be clearly referred to in the machine/plant documentation (user information
according to EN ISO 12100).
2.3

Machine safety in the USA

A key difference in the legal requirements regarding safety at work between the USA and
Europe is that, in the USA, no legislation exists regarding machinery safety that is applicable
in all of the states and that defines the responsibility of the manufacturers/supplier. Rather,
there is a general requirement that employers must ensure safety at work.
2.3.1

Minimum requirements of the OSHA

The Occupational Safety and Health Act (OSHA) from 1970 regulates the requirement that
employers must offer a safe place of work. The core requirements of OSHA are specified in
Section 5 "Duties".
The requirements of the OSH Act are managed by the "Occupational Safety and Health
Administration" (also known as OSHA). OSHA employs regional inspectors who check whether
or not workplaces comply with the applicable regulations.
The OSHA regulations are described in OSHA 29 CFR 1910.xxx ("OSHA Regulations (29
CFR) PART 1910 Occupational Safety and Health"). (CFR: Code of Federal Regulations.)
OSHA
The application of standards is regulated in 29 CFR 1910.5 "Applicability of standards". The
concept is similar to that used in Europe. Product-specific standards have priority over general
standards insofar as they cover the relevant aspects. Once the standards are fulfilled,
employers can assume that they have fulfilled the core requirements of the OSH Act with
respect to the aspects covered by the standards.
In conjunction with certain applications, OSHA requires that all electrical equipment and
devices that are used to protect workers be authorized by an OSHA-certified, "Nationally
Recognized Testing Laboratory" (NRTL) for the specific application.
In addition to the OSHA regulations, the current standards defined by organizations such as
NFPA and ANSI must be carefully observed and the extensive product liability legislation that
Safety Integrated
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Regulations and standards
2.3 Machine safety in the USA
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