CE CERTIFICATION. 1. Elimination - do we have to carry out this task? 2. Substitution - can we use a less hazardous substance?

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1 MACHINES PART II

2 CE CERTIFICATION As presented in Part I of this module, the traditional approach to the man-machine interface lies with guarding, interlocks etc., however as we adopt the new approach to machine safety, we cannot forget the basic principles, i.e. what we have identified as controls to be applied from our risk assessments. 1. Elimination - do we have to carry out this task? 2. Substitution - can we use a less hazardous substance? 3. Enclosure - is it possible to enclose the operation? 4. Segregation - so all these people have to enter this area? 5. Guarding - do we sue fixed, moveable or interlocks? 6. Information - is there sufficient information supplied to the operator? 7. Training - has the operator received sufficient training on the equipment to allow him to operate the machine safely? 8. Supervision - can the operator work alone or is there a need for some form of supervision? 9. Communication do we require audible or visual warning decals along with generic decals? 10. P.P.E - What type of PPE is required and to what standard do we require?

3 CE MARK The CE mark, in itself does not mean anything; it is merely a signal from the manufacturer or authorised representative of a machine, that it meets the essential health and safety requirements of the Machinery Directive (98/37/EC). It could be described as a passport for each machine to travel, unhindered throughout the European Union. Where a machine carried the CE mark AND is accompanied by Declaration of Conformity there is a presumption of compliance with the essential health and safety requirements. The Declaration of Conformity should clearly identify the special provisions that the machine is compliant with AND the harmonised standards used to make equipment compliant (EN s) A sample of a Declaration of Conformity is attached in Annex B. In some cases a manufacturer may apply the CE mark and issue a Declaration of Incorporation, which essentially, is the same as a Declaration of Conformity with the exception that there is a statement at the bottom of the certification stating that the equipment must be installed in lie with the essential health and safety requirements of the Directive if the CE mark is to be valid. This Declaration of Incorporation occurs when the manufacturer is supplying his equipment that he has no control over it s final installation, e.g. An electrical control panel Agitator

4 HARMONISED STANDARDS European Union harmonised standards are those set down by a select committee in relation to specific machines or components of machines. There are three basic types of Standards, namely: - A Standards: B Standards: C Standards: These are the fundamental safety standards, which give the basic concepts for design and general principles. (EN 292-1: 1995, EN 1050: 1993) Deal with specific aspects of safety related devices (EN 294, EN 954-1/1A, EN ) Clearly lay down specific requirements of machinery and has priority over A and B type standards, however, A and B standards are already incorporated into the C type. (EN 692, EN 415, EN 201). EN standards are available for purchase through the National Standards Authority of Ireland (NSAI) [

5 EN STANDARDS - COMMON There are a few EN s that all people involved in the design of machinery, its purchase or as a safety practitioner should have available to them and it is these standards (non exhaustive) that underpin the traditional approach to safety, namely: - EN 292-2: EN 1050: EN 294: EN 1037: Safety of Machinery Basic Concepts and General Principles for Design Risk Assessment Safety Distances to Prevent Danger Zones from being reached by the Upper Limbs Safety of Machinery Prevention of Machinery from Unexpected Start Up EN 1088: Safety of Machinery Safety of Control Systems Interlocking Devices EN 954-1/1A: EN : Safety of Machinery Safety of Control Systems Safety of Machinery Safety of Electrical Equipment of Machines All of the above should be contained in any library used by designers, supervisors, engineers, safety practitioners or manufacturers of machinery.

6 EN 292-2: 1995 This particular standard is essentially the bible for all machinery and is compulsory reading for all people involved in machine safety, since it lays down specific requirements for all types of machines. The standard is a mirror image of Annex I of the Machinery Directive (98/37/EC) and is broken down into specific areas, namely: - Principles of Safety Integration Materials and products Lighting Design of Machinery to Facilitate its Handling Safety and reliability of Controls Control Devices Starting Stopping Emergency Stop Mode Selection Failure of the Power supply Failure of the Control Circuit Software Stability Risk of Break-Up Risks due to Falling or Ejected Objects Risks due to Surfaces, Edges or Angles Combined Machinery Variations in Rotational Speeds Prevention of Risks due to Moving Parts Characteristics of Guards and Protection Devices Special Requirements for Guards Fixed Guards Moveable Guards Adjustable Guards Protection Devices Electricity Supply Static Electricity Energy other Than Electricity Errors in Fitting Extreme Temperatures Fire Explosion Noise Vibration Radiation

7 External Radiation Laser Equipment Emissions of dust, gases etc. Risks of being trapped in the Machine Risks of Slips, Trips or Falls Maintenance of Machinery Access to Operating Position and Servicing Points Isolation of Energy Sources Operator intervention Cleaning of Internal Parts Indicators Information Devices Warning Devices Warning of Residual Risks Marking Instructions

8 PRINCIPLES OF SAFETY INTEGRATION The General principle of safety integration is that amongst other things, machinery must: - Be so constructed that it is fitted for its function and can be adjusted and maintained without putting persons at risk, when these operations are carried out under the conditions foreseen by the manufacturer. The aim of the measures taken must be to eliminate any risk of accident throughout the foreseeable lifetime of the machinery even when there are foreseeable ABNORMAL situations Have all risks eliminate or at least reduced to an acceptable level Appropriate control measures must be commensurate with the risk Supply users with sufficient information so as to operate the machinery safely Be accompanied by sufficient information and instructions so as to provide the user with sufficient information and know how to operate the equipment safely. Provide an ergonomically acceptable workstation Et al

9 GENERAL REQUIREMENTS OF GUARDS An interesting definition can be found in the Oxford Dictionary, namely a guard is, amongst other things: - Protect from Harm Watch over and Defend Control Entry or Exit Provide with a Protective Device Provide with Safeguards Take precautions Vigilance and Watchfulness The Machinery Directive (98/37/EC) has a general requirement for guards, in they must: 1. Be of robust construction 2. Not give rise to any additional risk 3. Not be easy to by-pass or render non-operational 4. Be located at an adequate distance from the danger zone 5. Cause minimum obstruction to the view of the production process 6. Enable essential work to be carried out on installations and/or replacement of tools and also only to be the area where the work has to be done, if possible without the guard or protection device having to be dismantled. SPECIAL REQUIREMENTS OF GUARDS FIXED GUARDS Fixed guards must be securely held in place. They must be fixed by systems that can be opened only with tools. Where possible, guards must be unable to remain in place without their fixings. MOVEABLE GUARDS Moveable guards must: - As far as possible remain fixed to the machinery when open Be associated with a locking device to prevent moving parts starting up as long as these parts can be accessed and to give a stop command whenever they are no longer closed. Type B moveable guards must be designed and incorporated into the control system so that: -

10 - moving parts cannot start up while they are within the operator s reach - The exposed person cannot reach moving parts once they have started up - They can be adjusted only be means of an intentional action such as a tool, key etc. - The absence or failure of one of their components prevents starting or stops the moving parts - Protection against any risk or ejection is proved by means of an appropriate barrier ADJUSTABLE GUARDS Adjustable guards restricting access to those areas of the moving parts strictly for the work must: - Be adjustable manually or automatically according to the type of work involved Be readily adjustable without the use of tools Reduce as far as possible the risk of ejection REQUIREMENTS FOR PROTECTION DEVICES Protection devices must be designed and incorporated into the control system so that: - Moving parts cannot start up while they are within the operator s reach (EN 1037 and EN 1088) The exposed person cannot reach moving parts once they have started up (EN 294 and EN 953) They can be adjusted only be means of an intentional action, such as the sue of a tool, key etc. The absence or failure of one of their components prevents starting or stops the moving parts

11 WHAT ARE PROTECTION DEVICES? Protection devices are also known as safety components and must themselves be CE compliant and consist of: - 1. Interlock switch 2. Light Curtain 3. Pressure Sensitive Pad 4. Two Handed Control 1. INTERLOCK SWITCH An interlock switch is a device, normally, but solely connected to a moveable guard, that when opened, will stop the machine in a safe manner. Some interlocks can be captive in nature, i.e. where for example there is a run down time for the machine, the interlock will not allow the guard door to be opened until the machinery has come to a safe stop. Harmonised Standard EN 1088 is a B class standard dealing with interlocks and their related functions. 2. LIGHT CURTAINS Light curtains or opto-electronic guards are generally used when the operator requires frequent access and in doing so is exposed to a risk (crushing, entanglement etc.). Opto-electronic devices, such as light curtains, reduces access time, i.e. the operator does not have to wait for the guard to open. Important Note Opto-electronic devices can only be used if the operator is not exposed to any risk of being hit by splashes or flying materials, likewise, the access time must be greater than the time needed to stop the machine. When considering the use of opto-electronic safety devices, the following parameters must be formulated, namely: - Define the zone to be guarded (EN 1050) Define the safety function to be performed (EN 294) Assess which Category of Safety is required (EN 954-1/1A) Calculate the Safety Distance (EN 999)

12 3. PRESSURE SENSITIVE PAD These are an alternative to mechanical guarding and will sense the presence of an operator or third party by contact, the two most common type being contact sensing bumpers as would be found on a moving trolley or a pressure mat. Both types are covered under EN (Safety of Machinery Pressure Sensitive Protective Devices). 4. TWO HANDED CONTROLS Two-Handed controls are used when it is necessary for the operator to keep their hands clear of the danger zone (e.g. punch press). These safety components are only of use to the operator and do not safe guard third parties who may enter the danger zone, therefore other safety controls must be used, e.g. three sided enclosure, the open side being directly in fornt of the operator. EN 574 governs two-handed controls (Safety of Machinery Two Handed Controls_, which defines three types of two-handed controls, namely: - Type 1 Type 2 Type 3A Type 3B Type 3C The minimum requirements for two-handed controls are: - Operators shall use both hands during the same time period; this is a simultaneous action and is independent of any time lag between the two input signals The two activating signals shall initiate and maintain the output as long as both signals are present. The release of one or both activating signals will stop the output The risk of accidental operation shall be minimised Prevention of accidental operation or prevention of defect shall be mainly achieved via mechanics and ergonomics The output signal may only appear when both inputs are activated within 0.5 seconds of each other (synchronous activation)

13 5. INSTRUCTIONS All machinery must be accompanied by instructions including the following: - Manufacturer name and address Safety precautions Weight/Mass of machinery Adjustments Maintenance How it is not to be used Drawings and Diagrams Lifting Points Vibration Noise Levels The above list is non exhaustive and the instructions should include all information, in a legible format that will allow safe use of the machinery for its foreseeable life cycle.