When conducting the assessment of meeting the minimum and general requirements of occupational health and safety (health and safety requirements), in case when the requirement is not confirmed and the answer is in the negative form, it is necessary to apply appropriate Security measures. The use of these agents should lead to compliance with health and safety requirements. This may be required by the machine user, eg repair of machine components and / or safety equipment, modernization or modification of the machine and / or safety equipment (supplemented with additional safety measures, change of technology and manufacturing conditions, etc.), changes in the conditions of use environment (eg improvement of general lighting), and even in the extreme case of an unacceptable possibility of solving the problem, it may lead to the decision to withdraw it from use (eg when the result of the estimation and risk assessment indicates its unacceptable level of risk). For sufficient risk reduction after the application of safety measures and thus fulfillment of a specific requirement, this risk should be reduced to a level corresponding to at least the legal requirements, taking into account the current state of science and technology.
The following hierarchy of activities' importance applies to risk reduction [1].
Safety solutions in themselves lead to avoiding hazards or reducing risks through the appropriate selection of constructional features of the machine and / or the interaction of exposed persons and the machine.
Considering the use of the machine in accordance with its intended purpose and the foreseeable use of incorrect, technical protective measures or supplementary protective measures are used to reduce the risk when it is not possible to eliminate threat or reduce the associated risk to a sufficient degree using construction solutions that are safe in themselves.
Information on the use, in terms of the residual risk identified should take into account first and foremost:
- machinery handling procedures corresponding to the personnel who will operate the machine or other persons potentially exposed to the hazards caused by the machine,
- recommended safe manners of the machine and associated requirements for required training,
- relevant information, including a warning about the residual risk occurring at different phases of life of the machine,
- description of individual recommended personal protection means, with justification for the need for their use and carrying out
Taking the above action should lead to a sufficient risk reduction, i.e. to the state in which:
- all types of work and methods of interference were taken into account,
- all hazards have been eliminated or the risks they pose have been reduced to the lowest level possible to achieve in practice,
- all new threats that have appeared with the protection measures introduced have been correctly demonstrated and appropriate protective measures have been taken,
- users have been thoroughly informed and warned about residual risks,
- compliance of the protective measures used has been achieved,
- the protective measures used do not adversely affect the operator's working conditions or the usefulness of the machine.
May protective measures allow easy use of machines in accordance with their intended use, so that they are not taken by the users to try to prevent or circumvent these measures. Such actions can occur, for example, if the protection measure:
- slows down the production process
- interferes with another activity
- conflicts with the user's preferences;
- it is difficult to use
- engages other people than the operator
- it is not recognized by the user
- it is not accepted as appropriate for the intended function.
In the case of machines and equipment used, their operation is related to ensuring that minimum safety requirements are met, which sometimes entails the need to carry out modernization works. The employer very often has to intervene in the construction of machines and also implements other activities, eg related to maintenance, ie: repair, regeneration, maintenance. However, if the user makes changes related to increasing the efficiency and quality of production, or changing the scope of the use of machines and equipment, he should take into account the binding European law I am lecturing: "a product that, after putting it into operation, has undergone significant modernization changes (modifications) is considered to be new".
In order to assess and maintain the technical condition of operated machines and equipment, first of all pay attention to the following aspects, set out in the Regulation [2]
Table 1.1. Features of control elements
|
Lp. |
Included feature |
Implementation of the required feature |
|
1 |
Way of marking |
· Clear subtitles in Polish · Using understandable symbols |
|
2 |
Location of the marking of control elements |
· On elements · On elements · Under elements |
|
3 |
Colors of control elements |
· Starting (turning on) - green or white (also gray or black allowed) · Stop (turn off) - red or black (also acceptable white or gray) · Emergency stop - red on a yellow background, distinguishing itself with a shape (button in the shape of a mushroom). |
|
4 |
Location of control elements |
· Preventing the operator from encountering dangerous elements of machines and devices: - moving parts of the drive - tools - sharp edges and corners - elements under electric voltage - hot surfaces - aggressive chemical substances |
Features of control elements related to the safety of use are presented in tables 1.1.
The control elements should also be protected against accidental change of position. The methods of implementing this requirement are presented in Table 1.2.
Table 1.2. Method of protecting control elements against accidental position change
|
Lp. |
Protection against accidental operation |
Way of security |
|
1 |
Construction and deployment |
· Piercing buttons in the housing or in the flanges · Keeping a proper distance between the control elements (preventing the unintentional start of several of them) · Cover the pedals |
|
2 |
The use of solutions forcing the operators to operate on control elements |
· Ensuring adequate minimum starting force (5 N) · Application of a double operating control lever (two different movements for attachment) · Use of a confirmation button (manual or foot control) · Mechanical protection in the off position (eg locks, key locks). |
The control panel should be located in such a way as to ensure that the operator can observe all workplaces. The operator must be able to check if there are other people in danger zones.
If this is not possible, then the safety system should automatically send an acoustic or optical warning signal before starting the machine, which can be picked up from all machine servicing stations. The time between sending the signal should be long enough for the exposed person to avoid danger (leave the danger zone or prevent the machine from starting (emergency cut-outs at workstation).
Provide an appropriate control system to exclude dangerous machine operation and maintain safety functions in the entire range of work and conditions of use (temperature, humidity, vibrations, impacts, electromagnetic fields, etc.) . Control system components that perform safety functions should have adequate resistance to defects (eg power loss or fluctuation, short-circuit between wires, failure of a contactor, relay or distributor, disconnection of Å, Safety connector, compression spring, erroneous operation of the software).
The construction of the control system is to prevent the machine from starting up in an unpredictable and automatic manner in hazardous conditions (movement of tools, workpieces, etc.). Conditions under which an unexpected start-up occurs in the following circumstances:
- after removing the defect of the control system
- after resuming the power supply
- after emergency stop
- after protective devices have operated in hazardous conditions (blockade, non-contact protective devices)
- after closure of moving blocking devices in hazardous conditions
- Immediately after connecting the machine to the power source (without triggering a start signal via the control element).
Machines should be equipped with a control system designed for complete and safe stopping them. Depending on the type of hazard at the workplace, there should be control elements designed to stop the whole machine or some of its parts, so that the machine is safe. On the other hand, the power supply of the corresponding machine drives is disconnected if the machine or its dangerous parts are stopped.
The controls should be positioned so that the operator can see the elements being stopped. The STOP function should have priority over the start function (START). This means that with the simultaneous actuation of the control element to start and stop, the machine can not be started and should stop when moving.
Activation of the machine stopping system should not cause hazards, eg in the form of sudden effects of inertia, as well as the presence of residual other energy (loosening, skidding of tools and objects in handles, tearing tools, collision of materials and workpieces, loss of stability due to workpieces, etc.).
Due to the dangers posed by moving parts of the machine, its drives or moving tools or workpieces, and depending on the time they are stopped, the machine is equipped with a device for emergency stop. The emergency stop controls shall:
- be easily accessible
- be in all places and positions occupied by operators (eg control panel, place of receiving and receiving materials),
- Be invisible from service stations.
The emergency stop device should effectively and irrespective of the type of machine operation, disable all dangerous movements.
Due to the possibility of the machine being emitted or the substance and material being thrown out by the machine, the employee should be protected against mechanical injuries and thermal effects. The sources of danger in this case may be, for example: tanks with liquids or gases and pipes under pressure (stiff, flexible and connection of meat between tanks and equipment).
Protection against threats can be provided by:
- changing the position of workplaces in relation to sources of danger
- use of covers, insulation, etc.
- proper fixing of the wires with the media under pressure (eg with the use of handles, hooks, supports, etc.).
- use of housings, screens, covers in places of anticipated steam, water, liquid metal, plastic and other pressure under pressure.
To provide protection against falling or thrown objects:
- fix tools and workpieces in properly selected holders, devices or tables with assembly holes.
- use guides and steady for workpieces.
- equip machines with suitable devices to prevent the recoil of the workpiece
- use position limiters to protect against exceeding the extreme positions and against the fall of parts of machines and devices (from the slats, guides, etc.)
- use limiters for the position of transported materials and products (from conveyors, cranes, etc.)
- ensure adequate mechanical strength - shields, screens, hazardous zone enclosures (allowing absorption of energy of ejected objects and tools).
In order to reduce the emission of harmful factors in the working environment, it is necessary to use housings, hoods, suckers and other devices (which capture harmful factors) located near the emission sources and cooperating with the device local extraction.
Separation or disintegration of parts of machines is prevented by the selection of suitable materials for their construction, characterized by:
- appropriate mechanical properties,
- Corrosion resistance, abrasion resistance, etc.
- adaptation to the existing working conditions (pressure, speed, temperature, humidity, etc.),
and the right choice of the construction of the cover in places of the anticipated zones of detachment or disintegration of parts of the machines.
A machine exposed to overturning or making unintentional movements under the influence of external and internal forces (eg wind pressure, vibrations, shocks, stress) should be fastened to the ground. For this purpose, for example, handles, anchors, bolts can be used.
Use shields (fixed or movable) or other protective devices (so called technical non-glazed protective means) that prevent contact with moving hazard elements, i.e. power transmission elements (shaft , Y, couplings, belt gears, chain, etc.) and components in the working area (tools, workpieces).
Shields should meet the following requirements:
- the use of materials corresponding to the conditions of the work process (resistance to temperature, corrosion, abrasion resistance, adequate strength, impact resistance, etc.)
- no sharp edges and corners
- certainty of connection with the machine during operation (protection against unexpected opening, dropping, position change, etc.)
- location in relation to the danger zone (movable elements) with preservation of the so-called the safety distances specified in the PN
- the possibility of convenient observation of the work process (choosing the right shape and location, applying transparent materials or holes in the cover)
- choosing the type of shield depending on the frequency of access to the danger zone (fixed cover, movable blocking, mobile blocking with locking, mobile automatic, steering)
- adaptation to the number and location of hazardous zones (local cover, entire enclosure).
Local lighting should be provided (when general lighting does not provide proper lighting parameters for work zones and locations for setting, maintenance and repair activities) and the type of sources appropriate for the type and location of the activities , Light (incineration, discharge) and fittings (taking into account the regulations and standards as well as the results of lighting measurements).
It should be impossible to contact human with elements of very high or very low temperature (fire, hot products and waste, tools, installations). For this purpose you can use:
- covers, covers or screens,
- insulating materials (inside or outside of devices).
The machines should be positioned in such a way as to eliminate the need for the operator to stay in the place where the hazard occurs. Areas (surfaces) posing a threat should be appropriately marked.
Excellent and / or acoustic signaling informing about hazardous situations (starting the machine, changing parameters, failure), should be selected so that the signals generated are unambiguous - they were made Easily notice and distinguish from other signals.
To do this, use:
- intermittent (blinking) light signal to inform about a greater risk or a more urgent need for intervention
- a signal to indicate a smaller threat
- variable frequency auditory signal to inform about a greater risk or a more urgent need to intervene
- fixed-frequency audio signal to indicate a lower risk
- a warning signal in order to call for evacuation.
The lighting warning devices should be located in places easy to spot and selected in accordance with the signal being emitted, i.e .:
- red - failure, inaccuracy (threat situation)
- yellow - warning (abnormal condition, imminent danger situation)
- green - state of safety (normal state)
- blue - a condition in which operator action is necessary (informing about the need to take action by the operator).
Machinery and equipment should be used in accordance with the instructions and recommendations specified by the machine manufacturer in the instructions for use. During operation of machinery and equipment, particularly hazardous work may be performed. These are the works referred to in the regulation [3] and other regulations on occupational health and safety or in the operating instructions for equipment and installations. They can also be set by the employer as work of increased risk or performed under difficult conditions.
The employer is obliged to establish and update a list of particularly dangerous works occurring in the workplace. He should define the specific requirements of occupational health and safety while performing particularly dangerous work, and in particular ensure:
- direct supervision over these works by designated persons
- suitable protective measures
- instruction for employees, including in particular: the personal division of work, the order of performing tasks, the requirements of safety and occupational hygiene at individual activities.
The employer also ensures that only particularly authorized and adequately instructed persons have access to places where work is carried out.
The appropriate risk assessment for all activities performed by employees is essential for the safety of the operation of machinery and equipment. Conducting a risk assessment in the scope of all work performed by employees allows identification of all threats and raising awareness of their occurrence among employees, supervisors and the employer, and therefore the application of appropriate measures technical and organizational.
It is also necessary to properly organize the work taking into account:
- ensure adequate access to workstations, i.e. the appropriate dimensions of transitions between machines, as well as between machines and fixed elements of the premises
- ensure access and access to areas requiring service, adequate to the anthropometric dimensions of the operator, the type of activities performed and the tools used to obtain an acceptable level of risk.
An employer may also not allow an employee to work, for which he / she does not have sufficient knowledge of the rules and principles of occupational health and safety. The employer should inform employees about the hazards associated with machines located in the workplace or its surroundings and any changes introduced in them to the extent that these changes can affect safety, even when employees do not use these machines directly. The employee is obliged to confirm in writing to read the regulations and rules of occupational health and safety.
The employer should provide employees with the permanent use of current OSH instructions.
In addition to the technical condition of machinery and equipment essential for the safety of employees is their right choice and adaptation to the type of work performed. When choosing a user (employer) should take into account the specific conditions and type of work performed by him. It is also important to identify hazards that exist in the plant or workplace. When selecting machines and devices, the range of applications specified in the operating instructions (DTR), potential hazards due to operation in a given environment, spatial conditions and power supply at the place of machine installation are of particular importance. safe delivery and / or discharge of energy and raw materials and products, proper space (for carrying out maintenance, cleaning, repair and maintenance),
Appropriate qualifications should be provided to employees for the operation of certain groups of machines and equipment if service, repair, renovation or maintenance pose a safety or health risk to employees. The required qualifications are specified in the relevant industry regulations and depend on the type of work equipment and its parameters, eg servicing and driving motor-driven trucks, and exchanging gas cylinders in drive trucks with power transmission motor powered with gas, in accordance with the regulation of the Minister of Economy on occupational health and safety in the use of carts [4].
It is the employer's obligation to ensure that the employee is trained in the field of occupational safety and hygiene [5] before being allowed to work (initial training) and conducting periodic training in this area. Initial training consists of: initial general training , so-called general instruction and initial job training, so-called workstation instruction.During general instruction, an employee should be familiarized with the basic provisions of occupational safety and health contained in the Labor Code, collective labor agreements or work regulations, with the provisions and rules of safety and occupational hygiene in force in work site, as well as the rules for first aid in the event of an accident. The workplace instruction should provide the employee with familiarity with the methods of safe work using machines, including the occupational environment factors in his position, occupational risk related to the work performed and methods of protection against hazards . The station instruction ends with a test of knowledge and skills in the field of performing work in accordance with the provisions and principles of occupational health and safety. General instruction and workplace training shall be confirmed in writing in the initial training card, which is stored in the employee's personal files. Periodic training of employees servicing machines and equipment (employed in workstations) is carried out at least once every 3 years years, and at sites where particularly dangerous works are carried out, at least once a year [5]. This training aims to update and consolidate knowledge and skills in the field of occupational health and safety and familiarize employees with new technical and organizational solutions in this area. Periodic training ends with an exam checking the acquisition of knowledge covered by the training program. The organizer of this training confirms his completion with an appropriate certificate, which is stored in the employee's personal files.
Employees should be aware of the risks associated with machines and other technical devices in the area of the workplace or its surroundings, and any changes to them, to the extent that these changes have influence on machines and other technical devices placed directly in the area of the workplace and its surroundings, even if these employees do not use these machines and other technical devices directly. Employees should apply solutions to ensure that employees are trained:
- employees entrusted with the task of using machines have been properly trained, but also with regard to all threats related to this use, taking into account abnormal (abnormal) situations
- employees performing repairs, upgrades, maintenance or technical support have received specialized training in this area.
Maintenance work (lubrication, adjustment, replacement and replenishment of operating fluids) should be performed while the machine is at a standstill. Use (if it is not possible to carry out work while the vehicle is stationary) appropriate control devices (eg a stepper device - allowing to limit the travel distance of the risk element, the device being supported - maintaining the dangerous element movement only for the duration of the control button activation). When performing maintenance work, mechanical devices must be used to prevent unintentional change in the position of a dangerous part of the machine (eg under the influence of force of gravity, resilience), such as wedges, supports, struts, handles, etc. In order to record any repairs, reviews,
Electrodes for disconnection of electricity should be used and appropriately marked (eg insulated disconnectors, circuit breakers, plug-socket sets). For electric machines with a power of less than 1 kW and a current of less than 16 A, it is possible to use the plug-in socket connection in this case. Machines and devices should be used to cut off the inflow of gases, liquids, process steam and other energy carriers, and therefore appropriate markings have been introduced. Items of the power disconnecting elements should be marked to identify the status of "disconnection / disconnection". Devices for disconnecting from sources of energy should be locked in a disconnected position (eg a padlock).
If it is not possible to eliminate the threat by other protective means, use signs and / or security colors and other markings (pictograms, inscriptions). Signs of safety (prohibition, warning, order, evacuation and information) should be in accordance with the formulas specified in Polish standards. The safety marking must be placed in the place of the identified hazard or in its immediate vicinity. Places where there is a risk of collision with obstacles, falling or falling objects should be marked with safety colors - diagonal stripes alternately yellow and black or red and white (stripes drawn at an angle approx. 45 ° and having similar dimensions).
Provide adequate surfaces for walking or standing, reducing the risk of falling and slipping (eg corrugated metal, grille, anti-slip mat). Access to work zones located at different levels should be safe. This can be ensured by the use of stairs, ladders and working platforms equipped with 1.1 m high guard railings. In places where work is carried out at heights, anchor points for personal protection against falling from heights should be installed.
Electrical cables, gas, liquid and other media should be protected against mechanical damage, exposure to fire and other factors (by conducting conductors in floors, in pipes, suspension, etc.). It is necessary to use the installation and electrical equipment in a version adapted to the existing dangers (eg in explosion-proof version). Workplaces should be equipped with devices enabling control and maintenance of proper working parameters (temperature, pressure, voltage and intensity of electric current, etc.). Protection against fire, explosion and electric shock also serves technical solutions that cause that risks related to electricity are eliminated or prevented (e.g. application of anti-shock measures, if direct and indirect touch is possible, or closing of electrical devices to prevent access to them). There should also be solutions eliminating or limiting the possibility of creating dangerous electrostatic charges or means for their discharging (preventing the accumulation of charges or their discharging).
1. PN-EN-ISO 12100: 2011 Safety of machinery - General principles of design - Risk assessment and risk reduction
2. Regulation of the Minister of Economy of 30 October 2002 on minimum requirements for occupational health and safety in the use of machines by employees during work. Journal of Laws No. 191, item 1596 (as amended).
3. Regulation of the Minister of Labor and Social Policy of September 26, 1997 on general health and safety at work regulations (unified text). DzU 2003, No. 169, item 1650 (as amended).
4. Regulation of the Minister of Economy of May 10, 2002 on occupational health and safety in the use of carts . Dzu No. 70, item 650 (from late).
5. Regulation of the Minister of Economy and Labor of July 27, 2004 on training in the field of occupational health and safety. DzU No. 180, item 1860 (with amendments).