Essentials of Machine Safety

1. Essentials of Machine Safety Introduction Standards in Perspective

2. Introduction Why Safety? • Studies indicate 51% of workplace fatalities resulted from injuries from fixed plant and machinery. • Failure to adequately guard the machine was a factor in 37% of these cases. 69% of cases studies occurred in the manufacturing industry. • WorkSafe Australia processes 47,000 workplace claims per year for injury from machinery involving 5 or more days off work.

6. Research commissioned by the National Occupational Health & Safety Commission,(which was replaced by the Australian Safety and Compensation Council in 2005), examined the contribution that the design of machinery and equipment has on the incidence of fatalities and injuries in Australia. The study indicated that: of the 210 identified workplace fatalities, 77 (37%) definitely or probably had design-related issues involved. In another 29 (14%) who identified workplace fatalities, the circumstances were suggestive that design issues were involved. Design contributes to at least 30% of work-related serious non-fatal injuries. Design-related issues were most prominent in the ‘machinery and fixed plant’ group, and mobile plant and transport’ group. Similar design problems are involved in many fatal incidents. Design-related issues were definitely or probably involved in at least 50% of the incidents in the agriculture, trade and mining industries with between 40-50% of the incidents in construction, manufacturing and transport/storage industries. Solutions already exist for most of the identified design problems (such as seat belts, rollover protection and guarding)

7. Introduction Legal Framework

8. Introduction Legal Framework Occupation Safety and Health Act • The General Duties • Resolution of Issues • Safety and Health Representatives • Safety and Health Committees • Enforcement of Act and Regulations supported by Occupation Safety and Health Regulations • Set minimum requirements for specific hazards and work practices • Reference to National Standards developed by NOSH • Australian Standards developed by Standards Australia • National Standard of Plant and Guidance Material • Codes of Practice • Advisory Standards • National Codes of Practice and National Standards developed by the NOHSC • Australian Standards developed by Standards Australia

9. A Type AS 4360 Risk Management B Type EN954-1 EN418 EN294 IEC 61508 AS 61508 Functional Safety AS 4024 Safety of Machinery C Type AS1755 Conveyors AS1219 Power Presses AS2939 Robot Cells AS60621 Safety of Machinery AS61511 Process Safety AS61513 Nuclear Introduction Australian Standards

10. National Standard of Plant • Registrable Plant • Duties of Designers, Importers, Manufacturers, Employers etc

11. Safety is…. Lifecycle Management

12. Safety is…. Safety - Acceptable Risk Level • Risk 0 does not exist but it must be reduced up to an acceptable level • Safety is the absence of risks which could cause injury or damage the health of persons. • It’s one of the machine designer job to reduce all risks to a value lower than the acceptable risk.

13. Risk Assessment

16. Safety is…. Risk Assessment Principles • Machines are sources of potential risk and the Machinery Directive requires a risk assessment to ensure that any potential risk is reduced to less than the acceptable risk • Risk assessment consists of a series of logic steps which make it possible to systematically analyse and evaluate machinery-related risks • Risk assessment steps: • Identification of the potential hazard • Risk estimation • Risk evaluation • EN/ISO 13849-1 => Performance Level (PL) • EN/IEC 62061 => Safety Integrity Level (SIL) • Risk reduction

18. Severity Severity of injury S1 and S2 In estimating the risk arising from a failure of a safety function only slight injuries (normally reversible) and serious injuries (normally irreversible) and death are considered. To make a decision the usual consequences of accidents and normal healing processes should be taken into account in determining S1 and S2. For example, bruising and/or lacerations without complications would be classified as S1, whereas amputation or death would be S2.

19. Frequency Frequency and/or exposure times to hazard, F2 and F2 A generally valid time period to be selected for parameter F1 or F2 cannot be specified. However, the following explanation could facilitate making the right decision where doubt exists. F2 should be selected if a person is frequently or continuously exposed to the hazard. It is irrelevant whether the same or different persons are exposed to the hazard on successive exposures, e.g. for the use of lifts. The frequency parameter should be chosen according to the frequency and duration of access to the hazard. Where the demand on the safety function is known by the designer, the frequency and duration of this demand can be chosen instead of the frequency and duration of access to the hazard. The period of exposure to the hazard should be evaluated on the basis of an average value which can be seen in relation to the total period of time over which the equipment is used. For example, if it is necessary to reach regularly between the tools of the machine during cyclic operation in order to feed and move work pieces, then F2 should be selected. If access is only required from time to time, then F1 should be selected. NOTE: In case of no other justification F2 should be chosen, if the frequency is higher than once per hour.

20. Avoidance Possibility of avoiding the hazard P1 and P2 It is important to know whether a hazardous situation can be recognized and avoided before leading to an accident. For example, an important consideration is whether the hazard can be directly identified by its physical characteristics, or recognized only by technical means, e.g. indicators. Other important aspects which influence the selection of parameter P include, for example: ⎯ operation with or without supervision; ⎯ operation by experts or non-professionals; ⎯ speed with which the hazard arises (e.g. quickly or slowly); ⎯ possibilities for hazard avoidance (e.g. by escaping); ⎯ practical safety experiences relating to the process. When a hazardous situation occurs, P1 should only be selected if there is a realistic chance of avoiding an accident or of significantly reducing its effect; P2 should be selected if there is almost no chance of avoiding the hazard.

22. Safety is…. Safe Design “It is the control of the design and design-associated activity that leads to a responsibility as an obligation bearer, not their classification as a manufacturer, supplier, etc.”National Occupational Health and Safety Commision - Safe Design Project Report 2000

23. Principles of Safe Design Principles of Safe Design (of equal priority) The key elements that impact on achieving a safedesign are. Principle 1: Persons with Control – persons who make decisions affecting the design of products, facilities or processes are able to promote health and safety at the source. Principle 2: Product Lifecycle – safe design applies to every stage in the lifecycle from conception through to disposal. It involves eliminating hazards or minimising risks as early in the lifecycle as possible. Principle 3: Systematic Risk Management – the application of hazard identification, risk assessment and risk control processes to achieve safe design. Principle 4: Safe Design Knowledge and Capability – should be either demonstrated or acquired by persons with control over design. Principle 5: Information Transfer – effective communication and documentation of design and risk control information between all persons involved in the phases of the lifecycle is essential for the safe design approach. www.safeworkaustralia.gov.au

24. Safety is…. Making it safe Hierarchy of Control

25. Safety is….

26. Safety is…. Basic concepts • According to the requirements of standard EN/ISO 12100-1, the machine designer’s job is to reduce all risks to a value lower than the acceptable risk • It gives guidelines for the selection and installation of devices which can be used to protect persons and identifies those measures that are implemented by the machine designer and those dependent on its user • This standard recognises two sources of hazardous phenomena: • moving parts of machines • moving tools and/or workpieces

27. Safety is…. Reasonably Practicable How WorkSafe applies the law in relation to Reasonably Practicable WORKSAFE POSITION A GUIDELINE MADE UNDER SECTION 12 OF THE OCCUPATIONAL HEALTH AND SAFETY ACT 2004 (November 2007) In applying the concept of reasonably practicable, careful consideration must be given to each of the matters set out in section 20(2) of the Act. No one matter determines ‘what is (or was at a particular time) reasonably practicable in relation to ensuring health and safety’. The test involves a careful weighing up of each of the matters in the context of the circumstances and facts of the particular case with a clear presumption in favour of safety. Weighing up each of the matters in section 20(2) should be done in light of the following: • Likelihood • Degree of Harm • What the person knows about the risk and ways of eliminating that risk • Availability and suitability of ways to eliminate or reduce the risk • Cost of eliminating or reducing the risk

28. Advancements in Technology • Comms • Integrated Functions • Complex architectures 2010 1968

30. Machine Safety is…. Change of Standards • The qualitative approach of the EN 954-1 is no longer sufficient for modern controls based on new technologies (Electronic and Programmable Electronic systems): • insufficient requirements for programmable products, • The reliability of the components is not taken into account, • too deterministic orientation (designated architectures). • Standard EN ISO 13849-1 will totally replace the EN 954-1 on 31 December 2011, and will upgrade the qualitative approach by the new quantitative(probabilistic) approach and is consistent with safety standards in general. • At the moment both standards EN 954-1 and EN/ISO 13849-1 are valid • For complex machines using programmable systems for safety-related control, the sector specific standard EN/IEC 62061 has to be considered • EN/IEC 62061 based on EN/IEC 61508

31. None of these measures are sufficient, however, without implementing a good safety culture. Change the work ethic/philosophy from Profit Motive > Production > Maintenance > etc. > Safety To Profit Motive > Safety > Production > Maintenance > etc. Choose 1 to have safety grafted on the side of other functions Choose 2 to have safety integrated within other functions

32. Functional Safety • Functional safety is part of the overall safety that depends on a system or equipment operating correctly in response to its inputs • Neither safety nor functional safety can be determined without considering the systems as a whole and the environment with which they interact

33. Two types of requirements are necessary to achieve functional safety: • safety function requirements (what the function does) and • safety integrity requirements (the likelihood of a safety function being performed satisfactorily).

34. Categories

35. Safety is…. • Reliability - the ability of a system or component to perform its required functions under stated conditions for a specified period of time.[1] It is often reported as a probability. • Probability is the likelihood or chance that something is the case or will happen.

36. Machine Safety is…. Standard EN/IEC 62061 • Specific to the machine sector within the framework of EN/IEC 61508: • gives rules for the integration of safety-related electrical, electronic and electronic programmable control systems (SRECS) • does not specify the operating requirements of non-electrical control components in machine (ex.: hydraulic, pneumatic) • The probability of failure associated to the required SIL (Safety Integrity Level) depends on the frequency of usage of the safety function to be performed Safety of Machinery application EN/IEC 62061

37. Machine Safety is…. Relationship Between Different Criteria • Relationship between Categories, DCavg, MTTFd and PL *In several application the realisation of performance level c by category 1 may not be sufficient. In this case a higher category e.g. 2 or 3 should be chosen.