Working at heights
- When standing on a ladder, do not work for more than 30 minutes at a time or more than a third of the working day.
- When choosing measures to prevent falls from a height, guards and safety nets must be preferred to personal protective equipment.
- Before using the lifting device and at the beginning of each work shift, make sure that the controls and safety devices are working.
Temporary work at height
In all places where there is a risk of falling during operation or movement, safety measures such as guard rails, safety nets and similar protective devices must be applied for fall heights of more than two metres.
These safety precautions must also be applied to lower fall heights, for example in work where manual handling of the weight increases the probability of falling or where there is a risk of falling into a construction metal deposit or into the water. If, due to the nature of the work, it is not possible to use guardrails or safety nets, safety must be ensured by the use of safety ropes or cables attached to a safety belt or harness.
Guardrails and safety nets
When choosing measures to prevent falls from a height, guardrails and safety nets must be preferred to personal protective equipment. Guardrails or safety nets must be in place if the height of a fall is at least two metres, including work on scaffolding, work platforms and walkways with open sides.
The guardrail must have at least foot rails, a handrail at a height of one metre and intermediate barriers at a height of 0.5 metres between them. The partition can also be replaced by appropriate tiles or safety nets. Safety nets must meet safety requirements. Different types of safety nets are used in different situations. For example, a horizontally installed safety net is used to prevent falling from the openings, and a vertical safety net in vertical guards. These safety nets must not be confused with nets installed on scaffolding, preventing material from falling.
The construction of wooden barriers must be based on the principle that their construction and condition ensure the safety of workers. If wooden posts are installed with a maximum distance of 2.25 metres between them, they will be fitted with partitions with a cross-section of at least 31x125 mm.
As a rule, railings and/or safety nets to prevent falls from a height must be installed before starting roof work. Guardrails or safety nets must be installed at the edge of the roof. No safety measures such as safety nets, work platforms or scaffolding with guardrails have to be implemented to prevent falls from a height, and anchored safety harnesses need not be used if the roof pitch is at least 15 degrees and the eaves higher than two metres. An additional guardrail or safety net near the work area must be installed on the roof with an incline of more than 34 degrees. Its distance from the working area must not exceed two metres on roofs with an incline greater than 60 degrees and five metres for a lesser incline. Guardrails must be attached to the edge of the roof with an incline of less than 15 degrees to prevent falls if the height of the eaves exceeds 3.5 metres. As an exception, in case of good weather conditions and non-slip roof surfaces, guardrails must be installed on the edge of the eaves more than 5 metres high. Installation and removal work must be safe, planned in detail and performed by trained professionals. For some work, the guards need to be temporarily removed – for example, near the roof edge when installing the roof covering. In such cases, the risk of falling must be avoided by the use of personal protective equipment (e.g. safety belts or harnesses with an anchorage system). If the roofing work is short term, such as repairing a leaking roof covering or removing snow, and the worker is secured with anchored seat belts or harnesses, the installation of guardrails and safety nets is not mandatory but still recommended. In the case of roofing works, failure of the roof covering material or falling from between the rafters must be avoided. Due to the combined effect of snow and human load, this is even more likely. The condition of the roof covering and its substructure can often be deceptive, and the condition of the roof covering, trusses and construction must be thoroughly examined before carrying out any work on the roof. Safety nets shall be installed between the rafters or beams throughout the working area. Walkways made of boarding or ladders are installed on the roof covering to distribute the load. Locations of roof guards or safety nets in accordance with the roof pitch in order to prevent falls. If the hazard cannot be avoided, an anchor harness is used.
Scaffolding is often used for facade work. The roof-mounted guardrail is also successfully replaced by scaffold-mounted guardrails, which are safer to install and allow safer and more convenient roofing work.
Scaffolding must be installed in such a way that its stability is maintained and that there are barriers or guardrails to prevent falls in dangerous gaps (handrails at least one metre high, foot rails and partitions between them at a height of 0.5 m). Scaffolding elements must be in perfect condition, durable and approved according to the manufacturer's instructions. As a general rule, the distance between the wall and the scaffolding must not exceed 30 centimetres. If the distance between the scaffolding platform and the facade is more than 30 centimetres, the scaffolding must also be equipped with internal barriers. The bottom surface must have sufficient load-bearing capacity. The soil on which the scaffolding is placed must be levelled and compacted. Rainwater must be drained from it. Load distribution tiles (e.g. plywood) must be used under the scaffolding legs. Scaffolding platforms must be installed in such a way that their parts do not move during normal use. The scaffolding is anchored to a permanent structure, such as masonry, unless it is designed to stand free. Accidental movement of scaffolding fitted with wheels must be prevented by means of wheel locking mechanisms, support posts, wheel chocks and the like. Scaffolding may only be installed, dismantled or modified by appropriately trained personnel. When working on scaffolding, the hatches of the work platforms must be kept closed. When guarding eaves, it is possible to use the guardrails installed on a scaffolding.
The installation of industrially made scaffolding in accordance with the instructions is a prerequisite for safety and generally does not require strength and stability calculations by a civil engineer or designer, as is required for self-made scaffolding, including wooden scaffolding. Wooden scaffolding must be made according to the design of a civil engineer or designer. Scaffolding located on the paths of machinery or at loading points must be protected against shocks, injuries and displacement. The area around the scaffolding is separated by barriers and marked with a warning sign. To prevent objects from falling down the scaffolding, they are covered with appropriate covers or nets. If part of the scaffolding is not ready for use during installation, or if the scaffolding is dismantled and modified, they must be marked with appropriate warning signs to prevent access to the danger zone.
Cage lifts and scissor lifts
A mobile cage lift and scissor lift is a device that is mainly used to lift a person to high places and to work there. When choosing a device, its suitability for the work to be performed must be assessed. The specifics of the lift’s ground surface, working height, mobility requirements, lifting capacity, lifting platform space, special requirements for electrical work, etc. must be taken into account. The lowest permissible air temperature when using the lift is generally –20 °C, as the properties of the hydraulic fluid do not guarantee safety at minus degrees.
The causes of accidents at work involving lifts include:
• using a lift that is not in a good technical condition;
• uneven or non-load-bearing soil;
• non-use of safety belts and harnesses;
• bumping into or getting caught in building structures;
• collision with a vehicle;
• overloading the lifting platform.
The lift must be used in compliance with the safety instructions in the manufacturer's operating instructions. Before using the lifting device and at the beginning of each work shift, make sure that the controls and safety devices are working. Visually inspect the machine for leaks or defects in the hydraulic and fuel systems on lines, hoses, tires, markings, safety barriers, etc. If the inspection reveals safety deficiencies, they must be rectified before use. If the emergency lowering of the lifting device works on batteries, make sure that they are charged first. When working with the lifting device, another person must be present nearby to safely lower the person in the cage in the event of danger.
Risk of falling
The work platform must not be slippery: ice, snow, oil, etc. must be removed. On a lifting device to be supported, all four support legs must be in full contact with the ground and locked, bearing the entire weight of the lifting (wheels off the ground). The lifting device must be level (this can be seen from the attached spirit level) and the ground sufficiently flat and load-bearing. Support tiles are used under the support legs. The support legs of the cage lift must be adjusted so that they are not damaged by the lifting device when the joint is rotated. The lifting capacity of the device must not be exceeded!
Workers must always stand on the base of the lifting platform and in no case sit or climb on barriers, stand on boxes, boarding, railings, ladders, etc. Cage lifts and scissor lifts use safety harnesses attached to the anchorage point. The maximum permissible wind speed when using the lifting device is specified in the operating instructions and on the device, and generally does not exceed 12.5 metres per second. It is also necessary to take into account objects on the lifting platform (posters, construction materials, etc.) that could increase the risk. When stopping at an incline after transport, the truck must be secured with brakes and wheel chocks.
Risk of collision and entrapment
A worker in the cage may be caught between the lifting cage and the structures, for example when manoeuvring near metal structures above their head. Therefore, care must be taken to ensure that each driving manoeuvre is correct. Avoid working while tired. In the case of a cage lift, the user must ensure that no unauthorised persons are present in the working area of the machine, especially near the base frame where there is a risk of being caught between the lifting apparatus. The boundaries of the danger zone must be marked, warning signs added and, if necessary, access restricted. When working in public places and near roads, traffic management must be organised by means of traffic control devices.