Section 1: General

1.1 Scope

This Published Document provides guidance on the safe use (see 1.3.22) of machinery, including that supplied prior to the implementation of the Supply of Machinery (Safety) Regulations 1992 [1].

It provides guidance on:

a) the basic principles of safeguarding, with reference to current harmonized European machinery safety standards; and
b) the continuing safe use of machinery manufactured in accordance with harmonized European machinery safety standards, in conjunction with the machine supplier’s instructions for use.

This Published Document is intended to promote a high standard of machinery safety. It describes and illustrates a variety of protective measures and explains methods by which it is possible to assess which measure(s) it is reasonable to adopt in particular circumstances. It is necessary, however, to consult speciﬁc legislation in applying the principles set down. Although reference is made to particular types of machine, speciﬁc recommendations are not given for every type of machine.

The guidance can be applied to machinery during its modiﬁcation, refurbishment, upgrading or change of use in order to satisfy the Provision and Use of Work Equipment Regulations 1998 [2].

NOTE 1 See also Approved Code of Practice: Safe use of work equipment [3].

NOTE 2 Signiﬁcant modiﬁcation, refurbishment, upgrading or change of use to existing machinery that results in, for example, changes of the measures used to reduce risk(s) or the introduction of a new hazard(s), can make it necessary to satisfy relevant requirements from the Supply of Machinery (Safety) Regulations 1992 [1], in particular Schedule 3.

NOTE 3 PD 5304 is not intended to be used as an alternative to the current harmonized European machinery safety standards for machinery supplied in accordance with the Supply of Machinery (Safety) Regulations 1992 [1].

1.2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

BS EN 953, Safety of machinery – Guards – General requirements for the design and construction of ﬁxed and movable guards¹⁾
BS EN 1037, Safety of machinery – Prevention of unexpected start-up
BS EN 1837, Safety of machinery – Integral lighting of machines
BS EN 60204‑1:2006+A1:2009, Safety of machinery – Electrical equipment of machines – Part 1: General requirements
BS EN 60947‑4‑1:2010+A1:2012, Low-voltage switchgear and controlgear – Part 4-1: Contactors and motor-starters – Electromechanical contactors and motor-starters
BS EN 60947‑5‑1:2004+A1:2009, Low-voltage switchgear and controlgear – Part 5-1: Control circuit devices and switching elements – Electromechanical control circuit devices
BS EN 61810, Electromechanical elementary relays
BS EN ISO 4413, Hydraulic ﬂuid power – General rules and safety requirements for systems and their components
BS EN ISO 4414, Pneumatic ﬂuid power – General rules and safety requirements for systems and their components
BS EN ISO 12100:2010, Safety of machinery – General principles for design – Risk assessment and risk reduction
BS EN ISO 13850:2008, Safety of machinery – Emergency stop – Principles for design (ISO 13850:2006)
BS EN ISO 13856‑1, Safety of machinery – Pressure-sensitive protective devices – Part 1: General principles for design and testing of pressure-sensitive mats and pressure-sensitive ﬂoors
BS EN ISO 13857:2008, Safety of machinery – Safety distances to prevent hazard zones being reached by upper and lower limbs
PD CLC/TR 50404, Electrostatics – Code of practice for the avoidance of hazards due to static electricity

1.3 Terms and deﬁnitions

For the purposes of this Published Document, the following terms and deﬁnitions apply.

1.3.1

failure to danger

any malfunction in the machinery or its power supply that increases the risk

1.3.2

guard

physical barrier, designed as part of the machine, to provide physical protection to persons from hazards

Note 1 to entry: A guard can either act:

a alone; it is then only effective when it is in the closed position for a movable guard or securely held in place as a ﬁxed guard; or
b in conjunction with an interlocking device with or without guard locking; in this case, protection is ensured whatever the position of the guard.

Note 2 to entry: Depending on its design, a guard might be called, for example, “casing”, “shield”, “cover”, “screen”, “door” or “enclosing guard”.

Note 3 to entry: Further information on types of guards and their requirements are given in BS EN ISO 12100:2010,6.3.3, and BS EN 953.

1.3.3

harm

physical injury or damage to the health of persons

1.3.4

hazard

potential source of harm to a person

Note 1 to entry: The term “hazard” may be qualiﬁed in order to deﬁne its origin (e.g. mechanical hazard, electrical hazard) or the nature of the potential harm (e.g. electric shock hazard, cutting hazard, ﬁre hazard).

Note 2 to entry: The hazard envisaged is either:

a) permanently present during the intended use of the machine (e.g. motion of hazardous moving elements, electric arc during a welding phase, unhealthy posture, noise emission, high temperature); or
b) might appear unexpectedly (e.g. explosion, crushing hazard as a consequence of an unintended/unexpected start-up, ejection as a consequence of a breakage, fall as a consequence of acceleration/deceleration).

1.3.5

hazardous area

space within and/or around machinery in which a person can be exposed to a hazard

Note 1 to entry: Also knows as “danger zone”.

1.3.6

integrity

measure of the ability of a machine, components, devices, systems and procedures to perform a required function under speciﬁed conditions

1.3.7

intended use (of a machine)

use of a machine in accordance with the information provided in the instructions for use

1.3.8

intensiﬁcation

increase in pressure above the relief valve setting

1.3.9

interlocking device

interlock

mechanical, electrical or other type of device, the purpose of which is to prevent the operation of hazardous machine functions under speciﬁed conditions (generally as long as a guard is not closed)

1.3.10

interlocking guard

guard associated with an interlocking device so that, together with the control system of the machine, the following functions are performed:

• the hazardous machine functions “covered” by the guard cannot operate until the guard is closed;
• if the guard is opened while hazardous machine functions are operating, a stop command is given; and
• when the guard is closed, the hazardous machine functions “covered” by the guard can operate (the closure of the guard does not by itself start the hazardous machine functions)

Note 1 to entry: BS EN ISO 14119 gives detailed provisions.

[SOURCE: BS EN ISO 12100:2010 ]

1.3.11

machinery

machine

assembly of linked parts or components, at least one of which moves, with the appropriate machine actuators, control and power circuits, etc., joined together for a speciﬁc application, in particular for the processing, treatment, moving or packaging of a material

Note 1 to entry: The terms “machinery” and “machine” also cover an assembly of machines which, in order to achieve the same end, are arranged and controlled so that they function as an integral whole.

1.3.12

protective device

safeguard other than a guard to provide physical protection to persons from hazards

Note 1 to entry: Examples of protective devices are given in Section 8.

1.3.13

protective measure

measure intended to achieve risk reduction, implemented by:

a) the designer (inherently safe design, safeguarding and complementary protective measures, information for use); and
b) the user (organization: safe working procedures, supervision, permit to work systems; provision and use of additional safeguards; use of personal protective equipment; training)

1.3.14

reasonably foreseeable misuse

use of a machine in a way not intended by the designer, but which could result from readily predictable human behaviour

1.3.15

risk

combination of the probability of occurrence of harm and the severity of that harm

[SOURCE: BS EN ISO 12100:2010 ]

1.3.16

safeguard

guard or protective device to provide physical protection to persons from hazards

1.3.17

safeguarding

protective measure using safeguards to protect persons from the hazards which cannot reasonably be eliminated or from the risks which cannot be reduced by inherently safe design measures

Note 1 to entry: BS EN ISO 12100 gives more information on safeguarding.

1.3.18

safety function

function of a machine whose failure can result in the immediate increase of risk(s)

1.3.19

safe working practice

safe system of work, i.e. a method of working that eliminates or reduces the risk of harm

1.3.20

scotch

mechanical restraint device placed manually or automatically between two parts of machinery and capable of preventing them closing under gravity or power

1.3.21

unexpected start-up

unintended start-up

start-up of a machine which, because of its unexpected nature, generates a hazard

Note 1 to entry: Unexpected or unintended start-up can be caused by, for example:

a) a start command which is the result of a failure in, or an external inﬂuence on, the control system;
b) a start command generated by inopportune action on a start control or other parts of the machine, e.g. a sensor or a power control element;
c) restoration of the power supply after an interruption;
d) external/internal inﬂuences (e.g. gravity, wind, self-ignition in internal combustion engines) on parts of the machine.

Note 2 to entry: Machine start-up during normal sequence of an automatic cycle is not intended, but could be considered to be unexpected from the point of view of the operator. Prevention of accidents in this case involves the use of safeguarding measures (see BS EN ISO 12100:2010,6.3).

1.3.22

use

activity involving machinery, including starting, stopping, programming, setting, transporting, repairing, modifying, maintaining, servicing and cleaning

PD 5304:2014

Guidance on safe use of machinery

Published:

31 Dec 2014

Withdrawn:

17 Dec 2019