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Erection and use of scaffolds At-guide B.3.2 January 2006 Replaces At-guide nr. 2.14.1 of September 1998 og nr. 2.14.2 of July 1998 This guide informs on rules in connection with erection, change of erection and dismantling of all types of scaffolds in all branches as well as the use of scaffolds. This guide does not comprise hoists, work platforms on one or two pylons, person lifters or work baskets hanging from crane hooks or mounted on fork-lifts A scaffold is a technical device used for temporary work in the height. Scaffolds are marketed in many different brands and can be produced in many different materials. A scaffold can be erected, changed and dismantled by the firm, whose employees and others will work on it later, or by a erection firm, whose task it is only to erect the scaffold. There are a lot of riscs combined with erecting and working on a scaffold, as the work is often done in the height, in akward working positions and often comprises handling of heavy burdens. Apart from this the weather impact plays a role in relation to the safety and health matters, both in connection with the erection of the scaffold and in connection with working on it. It is therefore necessary to comply with a number of safety precautions adressing the safety and health riscs of the work both in connection with the erection of the scaffold, in connection with working on it and in connection with the dismantling of the scaffold. Planning It is necessary to choose the technical device best suited for temporary work in the height. The device must be ergonomical suited in connection with the work task. It may therefore be necessary to chose another solution than a scaffold, f. ex. a lift, in connection with a concrete task of work. The developer If the scaffold is erected and used in connection with developing, where more than one firm are involved and where the firms together employ more than 10 persons at the building site at the same time, the developer must demarcate the common safety precautions, that is decide wether the scaffold is a safety precaution in the common areas, decide which entrepeneur shall erect the scaffold and which entrepeneur will be responsible for the scaffold in the period of building. In connection with the demarcation of the common security precautions and the making of the plan, the informations from the developer must ensure that the best suited technical device according to the concrete work tasks is chosen. If scaffolding is one of the common safety precautions it must be described in the plan for security and health. The plan must among other things include what kind of scaffold and scaffold construction is being erected, which enterprise is responsible for the scaffold, including the responsibility for inspection, maintenance and any changes, f. ex. moving of consoles while the scaffold is used, and who will dismantle and remove the scaffold after use. The projectmaker The projectmaker is obliged to ensure that the directions of his project are in accordance with rules of the work environment law, if a project has been created as a basis of the work. This entails that the projectmaker must indicate the precautions to be taken, f. ex which technical devices to be used, for work to be done temporarily above ground in the safest way possible. If the projectmaker states that scaffolding is to be used as a safety precaution, he must either describe the kind of scaffolding and scaffold construction to be used in regard to the tasks to be done from the scaffolding, or carefully describe the tasks to be done in such a way that whoever is going to choose the type of scaffolding may make a suitable choice. The choice of scaffolding type The choice of scaffolding type and construction must be done with regard to among other things: that the type can resist the expected workloads and any storing of material that the type can resist the strains from special equipment such as hoists, debris tube and covering that the type can resist the influence of the weather in the form of wind and snow that the type must be erected to give the optimal ergonomic work conditions, f. ex. more than 1.2 meters from sand blasting and [filtse] work that the width of the scaffold is safe regarding the use of technical equipment for horizontal transportation, such as wheelbarrow and window mounting cart that the working decks are placed at the right level regarding the work task that a separate staircase can be mounted at the scaffold to ensure safe traffic that the construction of the scaffold and the scaffolds shielding and covering safeguards the environment against being hit by falling tools, materials or debris. If work is to be done at more levels of the scaffold at the same time, f. ex. by façade restoration, only one level of decks may carry the load shown in the table above. (100%). The next level of decks, number 2, must only be loaded with 50%. Level number 3 and following levels must not be loaded. If the loading of the scaffold varies from this main rule, the necessary documentation showing that the stability and carrying capacity of the scaffold is in order must be at hand. Erection The enterprise The enterprise erecting scaffolds is responsible for the correct erection of the scaffold, regardless of it being a scaffold enterprise whose employees are not going to work on the finished scaffold or it being f. ex. a bricklayer enterprise, whose employees will work on the finished scaffold. The scaffold must have a width and be erected in such a way that work can be done in a proper way both with regard to safety and health. The work must be done under the supervision of a specially skilled person. He may be a skilled person, who on top of the special scaffold training also have knowledge of: The ground conditions of the place, where the scaffold is to be erected Building materials for fastening the scaffold, and where the scaffold is erected on top of a building construction, f. ex. a roof Types and constructions of scaffolds Computation af constructions Special knowledge of the work environment rules, f. ex. when to make a computation of construction for a scaffold construction. The specially skilled person must, beside the skilled direction of the work, check the erected scaffold after the erection. The enterprise must ensure that employees who erect, make changes to the erected scaffold or dismantle scaffolds have had the special training or have been instructed duly. The erection of the scaffold must be done in such a way and in such an order that the optimal safety of the erectors during work is ensured. Handling of scaffold materials, both horizontal and vertical, must be done with suitable tecnical means. The choice of transportation equipment, both horizontal and vertical, must be done under consideration of the task and concrete circumstances of the work place, f. ex. the surface and place for the storing of the scaffold materials and the transport on the erection site. The scaffold must be safely erected according to the sort of work, the conditions of the support, conditions of fastening, expectable strains such as weather conditions and other conditions influencing the stability and carrying capacity of the scaffold, such as shielding and debris shute. Only parts belonging to the same system of scaffold or parts which evidently are suited for joining must be used for erecting a scaffold. The joints and fastenings of the parts of the scaffold must be done in a sound way. Scaffold clamps must be suited for the purpose and may only be used, if the corresponding parts of the scaffold system are unusable. All used parts of the scaffold must be in a sound state free of damaging knarls, rot, cracks or corrosion damages. Training and instruction Only persons who have had a special training, deviced by the parties of the labour market and approved by the Danish Work Environment Authority or persons, who by their professional education and training are qualified to erect the type of scaffold in question, must partake in the erection, changes of the erected scaffold and dismantling of scaffolds higher than 3 meters. The following courses are offered in the building and construction trade: A one-day course in erecting wheeled and trestle scaffolds A three week course in system scaffolds, giving the right to erect wheeled and trestle scaffolds as well as frame and pylon scaffolds constructed as the manual of the type of scaffold in question states. After two years of practical experience ERFA I (two weeks) may be undertaken. This gives you a right to erect complicated constructions of scaffolds, f. ex. those which entails computation of the constructions. After one year more of practical experience ERFA II may be undertaken. This gives you a right to erect the total coverings that can be co-constructed with the construction of the scaffold. Furthermore there is a three week course in tube and coupling scaffolds, and a two year scaffold worker education. The vocational education and training for bricklayers and structurers comprises the systemscaffold education, which qualifies those educated after 2002 to erect wheeled, trestle and system scaffolds according to the manual of the type of scaffold in question (the erection manual). Employees, who before Juli 15. 2006 have gone through and passed the course of competence clarification for experienced scaffold erectors (the stoptest), may erect, make changes in an erected scaffold and dismantle scaffolds higher than three meters as well. Employees with great experience in erecting, making changes in an erected scaffold and dismantling scaffolds, f. ex. bricklayer's labourers with more than 10 years of experience before September 1. 1997 and scaffold erectors with more than eight years of employment before September 1. 1997 have the opportunity of sitting for the stoptest in system scaffolds. Only persons, who have received a special, comprehensive instruction may erect, make changes in an erected scaffold and dismantle scaffolds up to a height of three meters. The instruction must comprise the following: understanding of the erection manual for the scaffold in question safety during erecting, making changes in and dismantling the scaffolds in question preventive precautions for the risc of persons or things fall down safety precautions by changes in weather conditions, which might endanger the safety of the scaffolds in question allowed conditions of loading other conditions in connection with the erecting, making changes in an erected scaffold and dismantling scaffolds, f. ex. by erections in areas with traffick or in the vicinity of live wires Manual (manual for erection) The person supervising the erection work and the persons erecting the scaffold must be in possesion of a manual for the type of scaffold in question. The maual may be a manual from the manufacturer made by a special, skilled person, supplemented with informations on special details concerning the scaffold in question, if the erection and the use differs from the informations in the manual. If the scaffold is not erected in a standard erection, according to the informations in the erection manual, there must be a construction computation for the chosen scaffold construction which comprises a specification of the erection in question. The construction computation must comprise a strength and stability computation and be done by a person with a knowledge of computation of scaffolds, f. ex. a building engineer. If the work on the erected scaffold involves special precautions, f. ex. limitations or allocation of material stocking for the users, the manual must inform on this. Transport of scaffold material Suitable technical means, like trucks, cranes or lifts, must be used by unloading and loading trucks, both at the homesite of the enterprise and at the site of erection. If stocking of the scaffold material close to the erection site is not possible, f. ex. by erection in a back yard, a garden or where the road authorities or the police do not allow a truck to park, the transport of the material must be done with a suitable technical device, like a truck or a electrical cart. If the distance is short a handcart or a wheelbarrow may be used. Only in very special cases, where the use of a suitable technical devices is impossible and only when the scaffold is small, the material may be transported by hand. By vertical transport, when erecting and dismantling a scaffold, a material hoist must be used, either a bottom mounted electrical fitting hoist or a top mounted mini electrical fitting hoist. A rope hoist may be used when fitting and dismantling a debris tube, plastic and net shielding and the electrical hoist to be used by the employees who later will work on the scaffold. A rope hoist may be used ad well for hoisting a few light burdens in connection with work on the scaffold. Foundation/support The scaffold must be erected plumb and level on a stable, level and sustainable foundation. The foundation bases must rest on whole of their supporting face. Differences in levels of the ground may be evened out with half frames, adjustable base spindles or blocking-ups. If blocking-ups are used, they must not be higher than 0.2 meters and they must be made of suitable material, f. ex. wood. Porous materials, f. ex. porous concrete and bricks, must not be used as they might break. If the blocking-up consists of several layers, they must be soundly bound together. Pylons higher than 0.6 meters must be supported in two perpenicular directions. The wheels on transportable scaffolds or wheeled scaffolds must be brakeable and must be braked during use of the scaffold. Distance to a wall or some other stable part of the building The distance between the deck of the scaffold and a stable part of the builiding must under normal circumstances not excede 0.3 meters. If the distance excedes 0.3 meters you must mount an inner rail consisting of a hand and a knee railing. If the stable part of the building has openings, f. ex. big window openings, constituting a danger of falling into the building, you must mount a railing in the opening or mount an inner railing on the scaffold. If the scaffold solely has been erected for work on the roof and the lower decks of the scaffold are to be used only in connection with erecting and dismantling the scaffold, you must take special precautions in connectiong with the fastening of the scaffold where the distance between scaffold and the wall or other stable part of the building is more than 0.5 meters. The special safety precautions may be an inner handrailing, inner mounting decks on consoles or use of equipment protecting against falls. Anchoring Scaffolds, which are not constructed to stand by them selves, must be anchored according to the demands of the manual. The scaffold is anchored by fastening it to a sufficiently rigid construction, f. ex. a brick façade or another stable part of the building. The anchoring must be able to withstand the pull and push forces created by the use of the scaffold. If there is doubt about the stability of the construction to which the scaffold is anchored, f. ex. old brickwork og tree or sheet walls, the anchors must be tested with a pulling test apparatus. Choose the number and type of anchors stated in the manual for fastening a scaffold. If other types of anchors are chosen, you must be able to document that they can withstand the forces to which they are exposed. When judging the amount of extra anchors needed for fastening the scaffold, you must take into account the probable forces the scaffold will be exposed to, f. ex pull and push forces by wind, especially around shielding, mounted equipment like debris shutes, fitting hoists and electrical hoists as well as materials and tools used in connection with the use of the scaffold. Anchors must be placed in such a way that they do not hinder the work and the traffic on the scaffold. Brace anchoring can be used on unshielded scaffolds in normal situations. Tube anchoring can be used on scaffolds, which need extra strength, f. ex. by shielding with net or plastic as well by hoists, debris shutes or screens. Railings Railings must be put up every where a fall of more than 2.0 meters to the surrounding ground is possible. Railings can consist of a handrailing at the height of 1 meter, a knee railing at the height of 0.5 meter and a skirtinglist at least 0.15 meter high. The railing may consist of other forms of screening, if this gives the same amount of safety. You must mount inner railings at scaffold decks where the distance between the stable part of the building and the deck of the scaffold excedes 0.3 meters. Scaffolds fitted with fitting decks only used when erecting and dismantling of the scaffold must be supplied with an inner hand railing, where the distance between the wall or the stable part of the building excedes 0.5 meters. See the paragraph on distance to wall or other stable part of the building. Railings must be mounted when the height of fall is less than 2 meters if the sort of the work, the weather conditions or other conditions constitute a special danger. This f. ex. may be falling into stacked materials, reinforcement iron jutting out, light wells, stairs or basement steps. A hand railing must be fitted between head and console decks if the vertical distance between these excedes 0.5 meters. If the distance excedes 2 meters a full railing must be fitted. The railing must have the necessary strength and be soundly made. It must be able to withstand a horizontal load of at least 0.3 kN (30 kg) in the most unfavourable position and 1.25 kN (125 kg) in vertical pressure, cf. DS/EN 12811-1. The distance between deck and skirtinglist may at no point excede 30 mm, not even in a stressed position. If the railing has been removed temporarily, f. ex. to make it possible to hoist up tools or materials, other suitable precautions have to be taken to secure the employees, f. ex the use of equipment protecting against falls. When the task has ended, and always before the place of work is left, the railing must be refittet. The railing may be removed in connection with permanent access routes, f. ex. stair wells, but only at the point of entrance. If a material hoist or a building hoist for persons is mounted the railing must be exchanged with a barrier of the loading point made in accordance with current Danish standards: DS/EN 12158-1 for treadable material hoists, DS/EN12158-2 for non treadable material hoists or DS/EN 12159 for building hoists for persons. If work is done f. ex. at a building hoist (where the railing normally only consists of a handrailing) a railing or some other sort of screen must be established in full, as long as work is done at the site of the building hoist Scaffold decks Scaffold decks must always be soundly fastened to avoid shifting, tilting and the like. The fastening devices, f. ex. ball catch or pawl, must be checked regularly to see if they are in order and keep the deck locked to the frame. By atypical conditions of mounting, f. ex. if the type of scaffold in use is not directly compatible with the dimensions and layout of the building, it may be necessary to connect the decks of the scaffold with each other or to the construction of the scaffold with scaffold clamps or wire ties. Clamps with sliding parts must not be used. The use of console decks makes it possible to place the deck in a level giving ergonomical sound working positions, or the possibility of making the width of the scaffold greater. A console deck which is not placed in the centres of the scaffold must have a width of at least 0.6 meters. The special bracing or anchoring of the console decks must be done according to the manual of the type of scaffold in question. The drawing above shows an example of a scaffold with close covering for work on the roof. Access routes Appropriate placed and sound access routes in the scaffolding must be established. The access routes can be stairs, ladders, steep ladders or elevators for persons. The access routes of the scaffold must be without holes and openings or the like constituting a risc of falling through or stumbling. Scaffolds higher than 5 meters and longer than 10 meters and which are used by more than two persons at the same time, must have seperate stairwells with stairs. Separate stairwells must be places on the outside of the scaffold or at the ends. The distance between two stairwells should not excede 40 meters. If it is tecnically or practically impossible to establish seperate stairways, stairways may be established inside the scaffold. The same possibility exists from the upper main deck of the scaffold and up into f. ex. a gable. Stairs in access routes must have hand and knee railings. Landings in access routes must have a full railing consisting of hand and knee railings and a skirtingboard. If stairs are used as an access route, they must be slanted at an angle of 20°-45° and be made according to the formula 2 verticals + one step=61-63 cm. Step ladders must me made according to the formula 2 verticals+one step=54-66 cm. See the stair table. Stairs must have a width between the hand railings of more than 0.60 meters and must be secured against accidental unhooking and skidding (dislocation). Burdens carried up stepladders must be light and easy to handle. If ladders, both ladders mounted in the scaffolding and transportable ladders, are used as access route, the must be placed with a slant of 60°-75°, and be secured against overturning and sliding (displacement), f. ex. by fastenings to the mounting place. Transportable ladders must have a handle rising at least 1 meter above the point of access, f. ex. a fixed point on the string of the ladder, on the railing of the scaffold or on the stable part of the building. The access from stair or ladder must be unhindered and must not be established above a railing. The landings of the seperate staircases must be at level with the deck of the scaffold. A scaffold or parts of a scaffold, which must not be used for work, f. ex. because it is under construction, being changed or being dismantled, must be provided with warning signals (see the paragraph on signposting on a scaffold). The access route must be cut of physically, f. ex. with a bar. A plastic line must not be used. Each access opening in the deck of the scaffold must have a suitable size to ensure unhindered passage, and must be provided with hatches or coverings locked to the deck and being able to bear the same load as the deck. The hatchets must be secured in a locked position. Passing height The passing height must ensure that traffic and transport on the scaffold can be done in a sound manner. A height of 1.90 meters will be the starting point. Shielding Close shielding must be established in connection with portal frames and on the uppermost working deck, like in connection with work on roofs where there is a risk of dropping tools or materials. Close shielding means that openings in the deck must not let a ball with a diameter of 30 mm through. Close shielding may be made by fitting plywood sheets. Covering Covering protects employees against influences from the weather harmful to health during the winter period (normally form October 1. to March 31.). Covering also protects employees and people passing by, the environment, against any falling objects, like Tools, materials or debris. Covering protects against dust in connection with sand blasting as well. The protection can be erection of a screen or covering of the whole of the scaffold with net or plastic, a close shielding on decks of the scaffold and passing through frames to hinder drafts through trellis decks. Often a combination of the mentioned measures will be necessary to establish. Covering a scaffold will increase the load with the weight of the chosen covering material; increase the wind stress and the pressure of snow on horizontal surfaces. The increased strain on the scaffold by covering demands more anchoring, cf. the manual. By covering with net an increase of the anchoring forces by a factor of 2.5 may be expected, and by covering with plastic sheet the expected increase will be as much as a factor of 5. Stability and construction computations must be done for the whole system when covering buildings where the covering is coupled to the scaffold. The computation must include both the joining and the weight of covering of the scaffold and influences from weather conditions like wind and snow impact as well. Signposting on scaffolds An anchored and erected scaffold of more than two meters of height must be signposted by the erector before use. The signposts must be placed in sight f. ex by the entrance route. The signpost must clearly state The intended use of the scaffold, like windows exchange or roof work The maximum load stating the scaffold class (point load and load spread per m2) Date of erection Date of any last change Name of the enterprise that did the erection or the change Date of check before first use Signature The signposting must be made in a way and a colour clearly indicating, when the erection of the scaffold will be ended and the scaffold may be used, f. ex. with a red ”No trespassing” sign, when the scaffold is being erected, being changed or dismantled, and a green information posting, when the scaffold is ready for use. Transportation of material during use of the scaffold When working on a scaffold materials and tools are normally used. The transportation of these, both vertical and horizontal in the scaffold, must be planned and the best suited equipment for this must be chosen, cf. the paragraph on planning. For the vertical transportation this might be a building elevator for persons, a building hoist, an electrical hoist or the like. For the horizontal transportation the best suited equipment for the things to be transported must be chosen, like a brick cart for bricks. If a wheelbarrow, a brick cart, a window fitting cart or the like is to be used for the horizontal transportation on the scaffold, the free transportation width of the scaffold must be of a suitable size. Thus a wheelbarrow must not be used on a common frame scaffold because the width of the frames is too narrow. The anchoring and bracing of the scaffold must allow for the chosen way of transportation i. e. extra anchoring and bracing must be expected. Any up jutting ends of scaffold tubes must be marked and covered with a polystyrene block. To ensure the optimal use of the scaffold it is a good idea to mount an extra section of scaffolding at the place of the hoist. This will contribute to a better use of the scaffold as a work place. Storing, maintenance, check and scrapping Scaffolding material must be stored to keep it away from harmful influence. Scaffolding materials must be made of material with the needed strength, be sound and be free of harmful corrosion damages, rot and other faults that reduce the strength. Scaffolding materials must be handled in a way that hides faults and deficiencies. Before scaffolding materials are used in a construction it must be checked for being in a sound state. To document this systematic control procedure plywood decks must be marked every other year. Defective materials must immediately be removed from use. The directions of the manufacturer must state when scaffolding materials must be discarded or may be repaired. Any repair must be done in a sound and skilled way. Securing scaffolding against collisions Scaffolding erected in a site with a danger of collision must be secured against this danger and marked. Marking and mounting of traffic protection and the like must be approved by the local road authority. Securing scaffolding erected near aerial electrical wires if the scaffolding is erected near aerial electrical wires, precautions dealing with the danger of accidents must be taken before work is started, like That no work is done inside the distance of respect That the local utility company is contacted if working inside the distance of respect becomes necessary That electrical wires are insulated against touch That electricity is cut. The work of securing live electrical wires must only be done by qualified persons. Use Scaffolding used for work, stay and traffic must be erected to allow a fully safe and health wise sound use in relation to the work task in question. The enterprise, whose employees use a scaffold, is responsible for the scaffold being suitable for the task to be done from the scaffold, that the scaffold is in the prescribed state during use, even if the enterprise itself have not erected the scaffold. Employees who are to do work from a scaffold must be informed about and instructed in the special circumstances there may be in connection with the use of and the work from the scaffold, like That the scaffold is not used for work function for which it is not suited or aimed at That work must not be done at the scaffold when the weather constitutes a special danger, like heavy winds or snow That traffic only must be in the established entrance routes That hatches in entrance openings must be kept closed, when work is done at the scaffold That tools and materials must be placed not to constitute a danger to the employees themselves or the environment That materials and debris are placed and secured not to blow down That only light and easy handled burdens, that can be carried in one hand, are transported on the ladders placed as entrance routes That it is not allowed to jump down on the deck of a scaffold That the users are informed about the maximum load, both per m 2 and by point loads That only one level of the scaffold must be loaded with 100%, one with 50% and that the rest must not carry any load. If the load norm of the standard cannot be kept a documentation of the planned load must be made That the users are informed that changes in the scaffolding only may be done by the erectors of the scaffold or that something else has been agreed on. The work height of a scaffold must not be increased by ladders, trestle scaffold, stools or the like. If it is necessary in very special cases to increase the working height this must only be done by using suitable materials, which are soundly fastened to the construction. The entrance route to the extra working height must be sound and special precaution against fall must be taken by erecting extra railings or other kinds of screening or the like. Jens Jensen Read the instructions of the Trade Work Environment Councils as well The instructions of the Trade Work Environment Councils are found at www.bar-web.dk