3 MS Scaffolding

June 9, 2018 | Author: paansaeng | Category: Scaffolding, Mechanical Engineering, Nature
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METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKSMETHOD STATEMENT BS STANDARD PROJECT: WORK CLIENT : : SCAFFOLDING WORK Page 1 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS INDEX 3 INTRODUCTION 4 SCOPE OF WORK 5 MANAGEMENT GUIDANCES 6 APPLICABLE REGULATIONS AND STANDARDS 7 SCAFFOLDING DESIGN 8 SCAFFOLDING MATERIAL 9 GENERAL ERECTION PROCEDURES 10 SCAFFOLDING TYPES 11 INSPECTION 12 SCAFFOLDTAG SYSTEM 13 MODIFICATION 14 HAZARDS DURING ERECTION , USE AND DISMANTLE OF SCAFFOLD 15 SAFETY SIGNS AND BARRIERS 16 PRECAUTIONS DURING ERECTION AND DISMANTLE 17 REQUEST TO ERECT AND DISMANTLE BY USER / CLIENTLEVEL OF URGENCY 16 COMPETENCE AND TRAINING Page 2 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 1 INTRODUCTION This METHOD STATEMENT is specially prepared for the Provision of Specialist Scaffolding Services for the PROJECT to be undertaken by SCAFFOLDING CONSTRUCTION (SC) 2 SCOPE OF WORK SCAFFOLDING CONSTRUCTION (SC) has been invited to bid and upon successful award if the Contract will be engaged to provide Site Wide Scaffolding Services for the above-mentioned Project. The Scope of work shall be summarized below:iii) Provision of sufficient scaffolding materials, accessories, labor, hand tools, PPE and Supervision to meet the project site scaffolding requirements. iii) Responsible for the planning, design, erection, alteration, inspection and dismantle of any scaffolding work to British Standard as required to provide safe access and 100% fall protection in connection to all construction works and other related works of the project. 3 MANAGEMENT GUIDANCES SCAFFOLDING CONSTRUCTION (SC) shall - mandatory iii) Ensure that all its employees adhere to the recognized standard or code of practice with respect to the selection, erection and possible modifications of scaffolds. Appoint fully trained Scaffold Supervisors. Provide proper training for its scaffolders and ensure that the Scaffolding Supervisor properly monitors the performance of scaffolders. Provide adequate personnel protective equipment (PPE) such as gloves, coveralls, head protection, safety foot-wear, harnesses, lifelines, safety nets, and when working above water, life jackets. Ensure the proper use of all personal protective equipment (PPE) provided. Carry out regular quality control and safety checks on scaffolding materials and on erected scaffolds. Adhere to the written hand-over procedures and maintain good communication with the scaffolding Supervisor at all times. iii) iii) iii) iii) iii) Page 3 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS iii) Ensure safe dismantling of scaffolding and site clearance upon completion of the job. CLIENT shall: iii) Ensure at all times that scaffolding is safely used by users and not modified without authorization. Ensure that users report defects and unauthorized modifications of the scaffolding to the scaffolding supervisor. Ensure that users inform the scaffolding supervisor when scaffolding is no longer required and is available for dismantling. iii) iii) 4 APPLICABLE REGULATIONS AND STANDARDS i) BS EN 12811-1: 2003 ‘Temporary works equipment – Part 1: Scaffolds – Performance requirements and general design’. BS EN 39: 2001 ‘Loose steel tubes for tube and coupler scaffolds – technical delivery conditions’. BS EN 131-1:1993 ‘Ladders Part 1 Specification for terms, types, functional sizes’. BS EN 131-2:1993 ‘Ladders- requirements, testing, marking’. BS2482: Specification for Timber Scaffold Boards. BS5974: Code of Practice for temporarily installed suspended scaffolds and access equipment. iii) iii) iii) iii) iii) Page 4 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 5 SCAFFOLDING DESIGN The access and workings scaffolds listed in Table -1, with their construction criteria, shall be designed by SCAFFOLDING CONSTRUCTION (SC) in accordance with appropriate BS Standards. All other scaffolds, and all scaffolds which are the subject of a specific user request outside the prespecified format of Table 1, shall be designed by SCAFFOLDING CONSTRUCTION (SC) to the requirements and approval of client. Table 1 – Loads and Dimensions for Tubes and Fittings Scaffold Type of scaffold Use of scaffold Scaffold loading per m2 75 kg. Maximum number of working platforms 1 working platform 2 working platform Maximum spacing between standards 2.7 m. Typical load examples per bay 1 man+ tool. No materials 2 men+ tool. No materials Very light duty independent Very light duty independent General purpose independent Heavy duty independent Inspection access and painting Power cleaning, painting, light engineering Light engineering, e.g. welding or electrical Heavy engineering, e.g. large pipe work of structual 150 kg. 2.4 m. 200 kg. 250 kg. 2 working platforms+ 1at very light duty 2 working platforms+ 1at very light duty 2.1 m. 2 men+175kg.of materials 2 men+250kg.of materials 2.0 m. Special purpose To be stated on design drawings Page 5 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 3 SCAFFOLDING MATERIAL Scaffold Materials Standards Materials Steel Tube Standard BS 1139 Part 1 and 2 Additional Requirements. Only Galvanized tube to be used. Used tubes to be regularly inspected and cleaned. All tubes to be checked before used for corrosion and general condition, Defective tubes to be discarded. Butt welded tubes may be used on condition that the welding has been carried out to an approved procedure All fittings to be examined before use for damage and wear. Damaged or worn fittings to be discarded. No heat to be applied to fittings. Moving parts to be lubricated. To be clean and free of nails, free of warping and significant cracks. Not to be painted. Fitting BS 1139 Part 1 and 2 Boards BS 2482 When scaffolding is erected in areas where high levels of radiated heat are unavoidable encountered, e.g. where high temperature pipe work is in close proximity, timber scaffold boards may be exposed to the risk of burning or charring. In these circumstances, the use of pressed steel staging boards is an acceptable alternative. Note: Aluminium tubes, fittings, components and proprietary system frames are vulnerable in the case of fire and are potentially spark producing, If they are to be used where flammable atmospheres could be present during normal operations, their use shall be controlled the work permit system and precautions specified to ensure a safe atmosphere is provided. If a safe atmosphere cannot be reliably provided, equipment manufactured from steel shall be used. 7 GENERAL ERECTION PROCEDURES. There are many types of scaffolding that may be erected on a construction site, some of which are documented in this Code of Practice: The physical environment of the work area will determine the type of scaffold to be erected, however, there are safety precautions and recommended work practices common to all scaffolding. Page 6 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS a) Planning In order to satisfy the requirement of personnel intending to work from the working platform, the scaffolder will need to liaise with those personnel, the maximum load likely to be placed on the working platform, the area of working platform necessary to carry out the work, positioning of access ladders and a comfortable working height for the working platform will all need to be discussed. Any hazards involved with the erection shall be identified at the planning stage and appropriate precautions taken. Proximity to live electrical equipment or interface problems may need to be given consideration. b) Bracing & Ties. All scaffolds shall be braced and tied to form a rigid stable structure. There are minimum requirements for bracing and tying scaffold but these is a guide only to the scaffolder. A priority concern of the scaffolder is to provide a safe working platform free from movement. If this priority is not satisfied on completion of the minimum requirements for bracing and tying, the scaffolder is bound to include such extra ties and braces as in needed. i) Braces. With the exception of tower and single bay scaffolds, face braces shall be provided that are attached to the external row of standards of the scaffold as close to the junction of the ledger and standard as is practicable and extend to the full length and height of the scaffolding. Transverse braces shall be provided that are attached diagonally in every lift joining the internal and external standards at both ends of the scaffold and at intervals not exceeding 25 metres. Tower and single bay scaffolding shall be provided with braces diagonally in every face in every lift of the scaffold. ii) Ties. Ties shall be provided that are attached by 90 couplers to the outside and inside standards or ledgers as close as possible to the junction of ledgers and standards. They shall be located horizontally no further than one bay from the ends and at intervals not exceeding 3 bays. They shall be located vertically in the first lift and at intervals not exceeding 4 metres. c) Guard Rails All working platform above a height of 2 metres or at any height less than 2 metres where a hazard such as starter bars exists, shall be provided with double guard rails and kickboards to all open edges. The guard rails shall consist of a top rail erected 1 metre above the working platform and a midrail erected midway between the top rail and the working platform. Page 7 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS Kickboards shall extend a minimum of 200mm above the working platform and shall be secured firmly to the standards. Puncheons may be fixed to the guard rails to facilitate the securing of kickboards if necessary. d) Scafftags Upon completion of the scaffolding the scaffolder shall affix a scaffold complete Scafftag to the base of the scaffold at the point of access. The Scafftag shall display the following information; Location Ref. No. Date erected Requested by Built by Foreman Signature Safe Working Load During erection, alteration or dismantling of the scaffolding a scaffold incomplete sign of scafftag shall be displayed. Personal other than scaffolders are not permitted to access a scaffold while the incomplete sign or scafftag is displayed. e) Dismantling Prior to any dismantling of scaffolding taking place and during the dismantling procedure, the following safety precautions shall be observed: The scafftag is to be changed from “Complete” status to “Incomplete” status. The area at ground level is to be barricaded with general purpose bunting and a sign displayed stating “Danger – Men Working Above” All planks are to be turned to remove dust and dirt that may cause eye injuries. Care shall be taken to ensure personnel are not working below when plank cleaning is taking place. All horizontal tubes, once removed, shall be turned to the vertical to remove grit and metal flakes from inside the tubes to avoid eye injuries during lowering operation. 8 TYPES OF SCAFFOLD In all cases, the following scaffold types are to be subject to specific design by SCAFFOLDING CONSTRUCTION (SC) when the client may require to approve in detail prior to erection: Independent Tube & Fitting Scaffolding. Independent Modular Scaffolding. Tower Scaffolding-Tube & Fitting. Drop Scaffolding. Mobile Scaffolding-Tube & fitting. Birdcage Scaffolding. Cantilever Scaffolding. Light Duty Suspended Stages Page 8 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 8.1 a) INDEPENDENT TUBE & FITTING SCAFFOLDING. Definition An independent scaffold consists of two rows of standards, joined longitudinally by ledgers and transversely by transoms and / or putlogs and is braced and tied to form a rigid stable structure. b) Bay Sizes Heavy duty Medium duty Light duty 1.8m x 1.5m 2.4m x 1.5m 3.0m x 1.5m c) Loadings One working platform in a bay of independent tube and fitting scaffolding shall not be loaded in excess of following; Heavy duty Medium duty Light duty 625 kg 430 kg 180 kg The load to be placed on the working platform is to be distributed evenly over the area of the working platform but any concentrated loading is to be borne by the standards. No more than two working platforms are to be fully loaded per bay but this number may be increased provided the total loading per bay does not exceed the total of two fully loaded bays. d) Erection All gear to be used in the erection of an independent scaffold will be laid out nearly and sorted into sizes for easy access. It will be necessary to erect general purpose bunting around the gear so as not to create a trip hazard for other personnel. The area to be scaffolded will have general purpose bunting erected at ground level and a sign strating “caution – men working above“ displayed prominently to protect personnel from hazards involved in the erection of the scaffold. The surface to support the scaffold should be checked to ensure it is even and free from obstructions. If required, level the ground surface at the ground surface at the point’s standards are to be located. For ground surfaces other than concrete slabs, timber sole plates are to be placed at the required spacing for the scaffold to be erected, i.e. heavy duty, medium duty or light duty. Base plates of mild steel with an area no less than 0.0225m2 x 6mm thick are to be positioned on the sole plate. If the scaffold is to be erected on a concrete slab, the base Page 9 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS plates may be placed directly on that surface without the use of timber sole plate. The standards may then be placed on the base plates as required. Temporary raked tubes should be used to plumb the first two standards and may be removed at such time as the scaffold is self supporting through the fixing of addition member. Caution must be observed at this base lift of the scaffold to ensure joins do not occur in adjacent standards in the same lift and in adjacent ledgers in the same bay. Appropriate tube sizes are selected at the planning stage to satisfy these criteria. All horizontal members are to be made level and all standards made plumb with the use of an accurate spirit level. On completion of the base lift a two board wide platform is to be provided to enable scaffolders to erect the next lift. The minimum working platform width for use by scaffolders to erect all additional lifts is two boards. The working platform to be provided for other personnel at the required heights must conform to the standards set down in Section 4. During the erection of the scaffold, and while any alterations to the scaffold are being carried out, a “scaffold incomplete” sign is to be displayed prominently at the base of the scaffold. On completion of the scaffold, a “scaffold complete” sign is to be displayed prominently at the base of the access to the scaffold, and in a manner so as not to cause in to be dislodged by any inadvertent action. 8.2 a) INDEPENDENT MODULAR SCAFFOLDING. Definition Modular scaffolding consists of pre-fabricates members that lock together using a variety of patented fixing points located at approximately 0.5 m intervals on the standards. b) Bay Sizes Standard spacing for modular scaffolding may vary from those set down for tube and fitting scaffolding provided approval has been granted but the Department of Occupational Health Safety and Welfare / An example of this variation is the 2.4m transoms available in the wedge lock system that enable the scaffolder to erect 2.4m x 2.4m medium duty bays. The standard spacing is limited to the following:Heavy duty Medium duty Light duty 1.8m x 1.5m 2.4m x 1.5m 3.0m x 1.5m Page 10 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS c) Loadings One working platform in a bay of independent modular scaffold shall not be loaded in excess of the following; Heavy duty 625 kg Medium duty 430 kg Light duty 180 kg The load to be placed on the working platform is to be distributed evenly over the area of the working platform but any concentrated loadings is to be borne by the standards. No more than two working platforms are to be fully loaded per bay but this number may be increased provided the total loading per bay does not exceed the total of two fully loaded platforms. d) Erection All gear to be used in the erectin of independent modular scaffolding will be laid out neatly and standards sorted into sizes for easy access. General purpose bunting will be erected around the gear so as not to create a trip hazard for other personnel. The area to be scaffolded will have general purpose bunting erected at ground level and a sign stating “caution – men working above” displayed prominently to protect personnel from hazards involved in the erection of the scaffold. The surface to support the scaffold should be checked to ensure it is even and free from obstructions. If required, level the ground surface at the point’s standards arte to be located. For ground surfaces other than concrete slabs, timber sole plates are to be placed at the required spacing for the scaffold to be erected, i.e. heavy duty, medium duty and light duty. Adjustable base plates or “screw jacks” are to be positioned on the sole plates to accommodate the standards. If the scaffold is to be erected on a concrete slab the adjustable base plates may be placed directly on that surface without the use of timber sole plates. Caution must be observed at this base lift of the scaffold to ensure joins do not occur in adjacent standards in the same lift. Appropriate standard sizes are selected at the planning stage to satisfy these criteria. Legers, transoms and braces are fixed to the standards using the patented fixing methods and each member will be made level using the adjustable base plate and an accurate spirit level. Bracing is to be installed “progressively” at the required locations, not as an afterthought at the completion of the scaffold. Ties securing the scaffold to the building pr structure as set down in Schedule 6 of Occupational Health, Safety and Welfare Regulation 1988 are to be installed as an integral part of each lift. Page 11 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS On completion of the base lift, a tow board wide platform is to be provided to enable scaffolders to erect the next lift. The minimum working platform width for use by scaffolders to erect all additional lifts is two boards. The working platform to be provided for other personnel at the required height or heights must conform to the standards set down in Section 4. Where hop-up brackets are used as an extension of the working platform width, they must be restrained from rotation by approved tie bars. A two board hop-up bracket will not be used to accommodate one board. During the erection of the scaffold and while any alterations to the scaffold are being carried out, a “scaffold incomplete” sign is to be displayed prominently at the base of the scaffold. 8.3 a) TOWER SCAFFOLDING – TUBE & FITTING. Definition A tower scaffolding consists of four joined together longitudinally by ledgers and transversely by transoms and/or putlogs and is braced and tied to form a rigid stable structure. A tower is basically four parallel trusses on end and joined in the form of a box to support a working platform. b) Bay Sizes The minimum base dimension of a tower is 1.2m x 1.2m. The maximum base dimension of a tower is 3.0m x 2.4m. c) Height The maximum height of a free standing tower is three times the least base dimension measured centre to centre of the standards. The maximum height of a tied tower is 45 meters. The maximum height of a guyed tower is 15 meters. d) Loadings Not more than one working platform shall be erected on a tower scaffold although intermediary landing platforms may be erected for access to the working platform. The working platform on a tower scaffold shall not exceed the following loadings; Heavy duty Medium duty Light duty 625 kg. 430 kg. 180 kg. Page 12 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS e) Erection All gear to be used in the erection of a tower scaffold will be laid out neatly and sorted into sizes for easy access. It will be necessary to erect general purpose bunting around the gear so as not to create a trip hazard for other personnel. The area to be scaffolded will have general purpose bunting erected at ground level and a sign stating “caution – men working above” displayed prominently to protect personnel from hazards involved in the erection of the scaffold. The surface to support the scaffold should be checked to ensure it is even and free from obstructions. If required, level the ground surface at the points standards are to be located. For ground surfaces other than concrete slabs, timber sole plates are to be placed at the required spacing for the scaffold to be erected, i.e. heavy duty, medium duty or light duty. Base plates of mild steel with an area no less than 0.225m2 x 6mm thick are to be positioned on the sole plates. If the scaffold is to be erected on a concrete slab, the base plates may be placed directly on that surface without the use of timber sole plates. Temporary raked tubes should be used to plumb the first two standards and may be removed at such time as the scaffold is self supporting through the fixing of addition members. Caution must be observed at the base lift of the scaffold to ensure joins do not occur in adjacent standards in the same lift. Appropriate tube sizes are selected at the planning stage to satisfy these criteria. All horizontal members are to be made level and all standards are to be made plumb using an accurate spirit level. A spreader may be used to accurately guage the diagonals of the tower to ensure the standards remain plumb and prevent “corkscrewing” On completion of the base lift a two board wide platform is to be provided to enable scaffolders erect the next lift. The minimum working platform width for use by scaffolders to erect all additional lifts is two boards. The working platform to be provided for other personnel at the required height must conform to the standards set down in Section 5. When the span of the putlogs supporting working platform exceed 1.5 metres, they will be supported by a puncheon to a lower member, or strutted to lower members. During the erection of the scaffold, and while any alterations to the scaffold are being carried out, a “scaffold incomplete” sign is to be displayed prominently at the base of the scaffold. On completion of the scaffold, a “scaffold complete” sign is to be displayed prominently at the base of the access to the scaffold, and in a manner so as not to cause it to be dislodged by any inadvertent action. Page 13 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS f) Bracing Diagonal face bracing will be installed “progressively” on all faces of a tower scaffold. Where it is not possible to install such bracing due to protrusions from the building, that face will be tied in the manner outlined in AS1576 – 1974. Diagonal plan bracing shall be installed at every third lift of the tower scaffolding to the full height of the tower scaffolding. h) Access Towers Where the tower scaffolding is erected to provide access to a work area above 6 metres in height, the landing places for the ladders must be fully decked (except when access is provided). The maximum spacing between landing places shall be 6 metres. The platform shall have a safe means of access which shall always be on the narrowest side of the tower. Access may be achieved in the following ways: • By vertical ladders attached internally to the narrow side clear hand and foot holds shall be provided, by blocking pieces if necessary. Where vertical ladders rise more than 9 m, an intermediate landing shall be provided. By internal stairways or inclined ladders. By ladder sections integral with the frame members. These are to be climbed from inside the tower. Rungs shall be no more than 300 mm apart and the stiles no more than 500 mm apart. • • Climbing the tower by using the horizontal members is not permitted. With a prefabricated tower, access to a platform made of scaffold boards is difficult when the tower is climbed from the inside. Platform boards incorporating a trapdoor or hatch are therefore preferred. With tube and fitting tower, scaffold boards may be used and the platform constructed so that there is a permanent access opening adjacent to the ladder. This opening shall be as possible to allow safe access and provided there is adequate support, a loose cover may be used to protect the opening while people are on the platform. With a tube and fittings steel tower, the ladder shall, where possible, be lashed to the inside. If it has to be lashed to the outside, the access opening in the guard rail shall be protected by a hinged section or some other equally effective means. With all other towers, the ladder shall be fixed on the inside. Ladders shall never be placed on the platform to extend the height of the tower, nor shall be leaned against the side of a tower. Tools and heavy loads shall not be carried but hauled up or lowered down by a person on the platform within the confines of the tower. Page 14 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 8.4 a) DROP SCAFFOLDING. Definition A drop or hanging scaffold consists of two or more rows of standards, joined longitudinally by ledgers and transversely by transoms and putlogs and braced to form a rigid stable structure that is secured to overhead supports of sufficient capacity to withstand any load likely to be imposed on such overhead supports. b) Application A drop scaffold is erected where it is not possible or it is not practicable to erect a scaffold from the ground. c) Drop Tube Spacing The maximum spacing of drop tubes supporting the working platform of hanging scaffolding shall be as for medium duty and light duty independent tube and fitting scaffold. Medium duty Light duty 2.4m x 1.5m 3.0m x 1.5m Any work to be performed from the working platform of a drop scaffold requiring the drop scaffold to be erected to heavy duty specifications and shall only be erected with prior approval. d) Maximum Drop The maximum distance that a working platform may be erected from overhead supports is three lifts or six metres. Single lengths of tube only, are to be used as drop tubes, there are to be no joins or “dropping again” from ledgers or transoms. e) Loadings One only working platform per bay of drop scaffolding shall be loaded at any one time and such working platform shall not be loaded in excess of the following: Medium duty Light duty f) Erection All gear to be used in the erection of a hanging scaffold will be laid out nearly and sorted into sizes for easy access. The physical environment of the area to be scaffolded will determine whether the gear to be used in the erection of the scaffold will be passes up or 430 kg. 180 kg. Page 15 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS passed down. This decision will be made during the job safety analysis discussion between the work supervisor and the licensed scaffolders. Prior to commencement of work, the area at ground level beneath the proposed scaffold will be barricaded with general purpose bunting and a sign displayed prominently stating – “Danger – Men Working Above”. All gear to be used in the erection of the scaffold will have general purpose bunting erected around the storage area to prevent trip hazards to other personnel. i) Grid Mesh used as Overhead Supports Grid mesh may be used as an overhead support for drop tubes. An approved closed eye bracket welded to the end of the scaffold tube shall be retained in the grid mesh by a mild steel pin 20mm in diameter and 400mm in length. The pin shall be prevented from movement or dislodgement through inadvertent action by being lashed securely to the grid mesh with a suitable fire retardant lashing. Prior to raising or lowering the drop tubes into position a short tube approximately 300mm shall be fixed with a 90 coupler to the lower end of the drop tubes. This short tube affords the scaffolder a degree of comfort when erecting the initial ledgers and transoms and shall not be substituted by a 90 coupler. Scaffolders are permitted to access the lower end of the drop tube by sliding sown the tube to the “T” piece or by walking the steel beams if the former is not practicable. It is paramount for the scaffolder to secure his lanyard to the drop tube prior to descending to the “T” piece. The lanyard will be given two full turns on the drop tube and secured back to the second belt ring, and shall only be removed to relocate to another member. As there will be two scaffolders involved in fixing the first lift, it will not be necessary for either to traverse the longitudinal spacing between the drop tubes. This negates the practice of moving about during the initial erection stage without anti-fall protection. As early as is practicable the working platform planks and guard rails shall be installed and only when this is complete may anti-fall protection be removed. The nature of the overhead supports will cause the scaffold to sway considerably and must be eliminated as early as possible by bracing all faces of the scaffold and where possible, by the installation of ties. Subsequent lifts may be installed in the scaffolding at maximum spacing of 2 metres and are erected as for independent tube and fitting scaffolding. Where the scaffolder is in a stationary position during the erection of subsequent lifts, and guard rails are not provided, he will secure his lanyard to a member of the scaffold. Access shall be provided to the working platform via a ladder or ladders placed inside the drop scaffold. When more than one ladder is providing access to the working platform the landing place shall be fully decked except where access is provided through the decking. Page 16 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS The gap in the decking shall be fitted with guard rails and a swing rail to define the open edge or an approved trapdoor. Where it is not practicable to provide access to the working platform via ladders through the drop scaffold, alternative access will be provided. Personnel required to work from the working platform are not to placed in a hazardous situation to access the working platform. ii) Beams used as Overhead Supports Structural beams provide excellent opportunities for overhead supports for drop scaffolding. Purpose made beam clams only are to be used to lock tubes onto or into “I” beams. Tubes may be placed above or positioned inside the web of two parallel beams. In all cases they will be locked in position using beam clamps. Drop tubes are fixed to the horizontal tubes that are fixed to the beams using inverted 90 couplers and a check fitting positioned immediately adjacent to and above that fitting. In some cases it may be necessary to build temporary platforms to reach the next beam to be used as an overhead support. Temporary platforms can be spurred back to existing members to provide access to previously inaccessible beams. The scaffolder should always be prepared to erect temporary accesses to eliminate dangerous work practices. Scaffolders are not assessed on their ability to take risks but their ability to perform their duties in a safe and efficient manner. iii) Purpose Made Scaffold Tube Overhead Supports for Drop Scaffolding. Where structural members are of insufficient capacity to withstand the forces imposed on them by a drop scaffold or where there is no structure suitable as an overhead support, a structure may be erected using scaffold tube. This inboard restraint must be designed and erected to withstand three times the load likely to be imposed on the outboard projection of the needles. The outboard moments are to be calculated as being imposed at the fixing point of the outside standard to the needle. The inboard structure is erected with the needles projecting the required distance from the fulcrum point and the purpose made counterweights positioned the required distance inboard from the fulcrum as per the calculations. The counterweights will have their mass clearly stamped on them and locked onto the standard so as not to become dislodged. Temporary tension members shall be installed from the fulcrum to the needles to eliminate any bending of the needles under load. A minimum of two boards will now be positioned on the needles to afford the scaffolder a degree of comfort while fixing the drop tubes and under slinging the ledgers. Page 17 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS Prior to any work commencing on the outboard section of the scaffold the scaffolder will secure his lanyard to the fulcrum or other substantial anchorage. Under no circumstance is work to commence outboard, without anti-fall protection. All permanent tension members are to be in place and check fittings fixed appropriately before descending the drop tubes to the “T” pieces. g) Dismantling Drop Scaffolding When dismantling a drop scaffold the scaffolder is to commence at the top lift. This method will facilitate the removal of long tube be fixed to secure anchorages at all times and only removed to relocate to another member. The scaffold should endeavout to remove guard rails progressively on a multiple bay drop scaffold. This practice will enable a section of the lift to remain intact to pass the bulk of the gear up. When all members of the scaffolding have been removed the scaffolders return to the overhead supports by climbing up the drop tubes. Temporary tension members are again fixing to the needles and fulcrum to eliminate nay bending effect and the remainder of the scaffold may be dismantled. h) General Safety Precutions There are some general safety guidelines that must be considered when erecting or dismantling drop scaffolding; Whilst provision of safe access to working platforms is an integral part of erecting a drop scaffold, consideration must also be given to the point of access to and egress from the top of the ladder. A suitable landing platform at the top of the ladder is very important. Such landing platform shall be fully decked and guard railed. This is after the area personnel will set their tools and equipment down in preparation for lowering them to them working platform 11.7.2 Personnel should not be required to scale permanent edge protection or structure members to gain access to the ladder. Consideration must be given to a system of steps to eliminate this type of hazard. The nature of the work to be performed from the working platform may require the scaffold to be fully enclosed with a fire retardant material to protect those personnel working below. Page 18 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 8.5 MOBILE SCAFFOLDING – TUBE & FITTING. a) Definition A mobile scaffold consists of four or more standards joined together longitudinally by ledgers and transversely by transoms and putlogs and are supported by approved castors. The scaffold is braced in all faces to form a stable rigid structure. b) Bay Sizes Heavy duty Medium duty Light duty 1.8m x 1.5m 2.4m x 1.8m 3.0m x 2.1m Page 19 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS c) Loadings Not more than one working platform shall be erected on a mobile scaffold although intermediary landing platforms may be erected for access to the working platform. The working platform on a mobile scaffold shall not exceed the following loadings; Heavy duty Medium duty Light duty 625 kg. 430 kg. 180 kg. d) Height The maximum height of the working platform on a mobile scaffold is 3 times the minimum base dimension. It will be seen that this requirement will make it necessary to increase the base area of the scaffold I order to erect the working platform to a height greater than world be permitted by the area of one bay. When the base of a mobile scaffold is extended, the centre of the working platform must be located vertically above the centre of the base, providing that; When a wall, or the like, prevents the extension being used on one side, the base on the opposite shall be extended to give the required ratio. e) Castors No castor shall be used on a mobile scaffold unless it meets the following; The SWL is clearly stamped Pneumatic tyres prohibited Safe locking device Minimum diameter 125mm Eccentricity between the centre of the castor and the shank is less than 60mm Shank is not less than 150mm in length and is able to be properly secured in the standard. f) Bracing Diagonal face bracing shall be installed progressively on all faces of a mobile scaffold. Diagonal plan bracing shall be installed in the base lift as close to the castors as practicable and coupled in the centre using a swivel coupler. Plan bracing shall be further located in every third lift. g) Erection A mobile scaffold is effectively a tower scaffold supported on castors. As such the erection procedure applicable to tower scaffold is to be observed. The only exception is to be the substitution of base plates for castors. Page 20 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS h) Safe use of a Mobile Scaffold There are a number of points to be remembered when using a mobile scaffold to ensure the safety of all personnel. Castors are to have the locking device engaged at all times when stationary and only released for the purpose of shifting location. Personnel are not permitted to remain on the working platform when the scaffold is being moved. Planks are to be laid on uneven ground surfaces to allow the scaffold to be moved smoothly from one point to the next. Where possible the mobile scaffold is to be tied to a building or structure when stationary to restrict movement Access to the working platform shall only be gained via the ladder access provided through the centre of the scaffold. Planks shall not span the working platforms of two mobile scaffolds unless the mobile scaffold are tied together with ledgers. The maximum jacking adjustment on the castors shall not exceed 300mm. i) Light Aluminium Alloy Frame There are a number of patented designs of light aluminium alloy frame mobile scaffolds on the market. There is very little difference between brands and therefore a few general safety precautions cover the erection of these scaffolds. i) Loading The maximum load per platform unit shall not exceed 225kg. Not more than two platform units shall be loaded at any one time. ii) Bracing Two diagonal braces shall be provided to each longitudinal face between adjacent frames. Horizontal plan bracing shall be provided as near to the castors as possible, so that each standard supported by a castor is effectively braced. iii) Maximum Height of Working Platform The height of the working platform shall not exceed two times the least base measurement but in any event the height of the working platform shall not exceed 9 meters. Page 21 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 8.6 a) BIRDCAGE SCAFFOLDING. Definition Birdcage scaffolding consists of more than 2 rows of standard joined together by ledgers, and transoms or putlogs, and braced and tied to form a rigid stable structure. Birdcage scaffolding is used to gain access to ceilings and walls. b) Bay Sizes Heavy duty Medium duty Light duty 1.8m x 1.5m 2.4m x 1.8m 3.0m x 2.1m c) Loadings It is unlikely that birdcage scaffolding would ever require more than one working platform to be erected, as the most common application is for ceiling work. However, should there be a need for more than one working platform; it is permissible to erect a maximum of two. One working platform should not be loaded in excess of the following; Heavy duty Medium duty Light duty 625 kg. 430 kg. 180 kg. d) Bracing Diagonal bracing is to be provided on all faces of the scaffold and where necessary, internally to ensure a rigid scaffold. Where a birdcage scaffold is erected within a confined area, butt tubes may be used in addition to, or in substitution of, other bracing or ties, if the wall surface permits. In some cases the ledgers and transoms can butt against the wall to give the scaffold rigidity. Working Platform Except where access is provided, the working platform on a birdcage scaffold is to be closely planked at all times. There is to be no “hit and miss” with platform planks as specified in Occupational Health, Safety and Welfare Regulations. If there are insufficient planks to closely plank the whole area of the working platform then the area not covered shall be guard railed at the open edge. e) Page 22 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS f) Erection Erection procedure for birdcage scaffolding shall follow that of independent tube and fitting scaffolding. All safety aspects outlined are to be observed. It will be necessary in some applications of birdcage scaffolding to provide an inclined working platform. The maximum slope allowable before a stepped or terraced effect is incorporated is 1:6. Care must be taken to ensure the working platform planks are placed to run at right angle to the grade. This will eliminate any tendency for the planks to slide off the putlogs. Page 23 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 8.7 a) CANTILEVER SCAFFOLDING. Definition A cantilever scaffolding is supported by large cantilevered beams projecting from a building or structure with an inboard restraint capable of withstanding a force at least 3 times the outboard load. b) Bay Sizes Heavy duty Medium duty Light duty 1.8m x 1.5m 2.4m x 1.8m 3.0m x 2.1m c) Loadings Not more than two working platforms are to be erected and fully loaded per bay of scaffolding supported by cantilevered beams. One working platform is not to be loaded of the following; Heavy duty Medium duty Light duty 625 kg. 430 kg. 180 kg. d) Erection All gear to be used I the erection of a cantilevered scaffold is to be laid out nearly and sorted into sizes for easy access. It will be necessary to erect general purpose bunting around the work area and at ground level beneath the work area to warn personnel of an overhead hazard. A sign must be displayed prominently at ground level stating “Danger – Men Working Above”. iii) Positioning Beams The basis of all cantilever scaffolds is the needle beams and as such is critical to the safe erection of the scaffold. The job safety analysis discussion between the licensed scaffolder and supervisor should cover the following points regarding the beams; The dimension of the beam The ability of the pivot point to support the combined forces of the inboard and outboard The ability of the inboard restraint to withstand three times the force of the load out board The method to be employed to eliminate any lateral movement from the beams The first three points mentioned above require an Engineer’s verification. Page 24 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS The beams are positioned the required distance apart according to the standard spacings of the scaffold and projected the required distance outboard from the building or structure. The outboard distance is calculatd from the desired width of the working platform plus the clearance required from the building or structure to the working platform, plus 200mm. The inboard restraint toms are installed the required distance inboard and tied together and welded or bolted to the beam to prevent any movement. On completion of the inboard restraint of the beams, the scaffold can be erected on the projecting portion of the needle. All work to be preformed on the outboard requires the scaffolder to secure his anti-fall lanyard to a secure anchorage. iv) Erection of the Outboard A minimum of two boards are to be laid on the needles to afford the scaffolder a degree of comfort when erecting the scaffold. The standards are to be located on base plates welded to the beams at the required spacing. Ledgers are to be erected as close to the base of the standards as possible and secured to the top flange of the beam with purpose made beam clamps. The scaffold is erected as for tube and fitting independent scaffolding with attention being paid to ties and bracing. e) Formula to Calculate Unknowns Formula to calculate unknown:As we would always know the outboard specification of a cantilever scaffold and it is recommended that the inboard distance of the beams (pivot point to inboard restraint) is three times the outboard distance, the counterweight or onboard restraint is the only calculation likely. The following formula is used to find the unknowns: CW x D – d x 1 x 3 CW D = = inboard restraint inboard distance d 1 3 = = = outboard distance outboard load safety factor When calculating the outboard load the mass of the components of the scaffold must be considered as they make up part of the load. The outboard distance is calculate as the clearance from the pivot point to the inside standard of the scaffold plus 2/3 the width of the scaffold. f) Access A safe access is to be provided to the working platform. The ladders are to be positioned through the centre and all landings are to be fully decked and guard railed. All manholes to facilitate the positioning of ladder are to be guard railed and a swing gate installed. Page 25 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 8.8 a) LIGHT DUTY SUSPENDED STAGES. Definition A light duty suspended stage means a working platform suspended from overhead supports and ; The means of lowering or raising the stage, whether those means are operated by hand or are power driven The overhead supports, attachments and tracks ; and The means of suspension b) Platforms Although it is quite possible to construct a platform suitable for a light duty suspended stage from scaffold tube it is unlikely that it would be necessary. With the availability of patented prefabricated systems to the market, the task of erecting a suspended stage has Page 26 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS been simplified. This section of the Code of Practice will concentrate on the prefabricated units. Should the scaffolder be required to construct the working platform from tube and fitting, approval by SAS Accident Prevention Superintendent will be necessary. There are a variety of platforms available, some single units and some component assemblies that allow the length of the platform to be varied. However, there are some basic requirements that apply to all platforms; III) IV) V) The platform is to be of rigid construction and neither more than 600mm nor less than 500mm wide. The platform is to have guard rails securely fixed around the outer edges. The platform is to have fender boards of not less than 100mm fitted to all edges. VI) SWL to be clearly displayed. c) Overhead Supports The overhead supports of a light duty suspended stage will vary with individual job applications but can basically be divided into two categories. They are ; IV) V) Purpose made modular or scaffold tube overhead supports Structure members of the building or structure The over-riding requirement of any overhead support of a light duty suspended stage is that it must be able to withstand a force equivalent to three times the maximum load to be suspended from such overhead support a) Purpose Made Modular Overhead Supports Manufacturers of light duty suspended stages market the overhead supports to suit there gear. Many are telescopic which makes for easy transportation and have a locking device to retain them at the required extension. The overhead supports must be prevented from moving laterally by being tied together or in some other way prevented from moving to the satisfaction of the Supervisor. They must be counterbalanced by weight as follows: Have a weight not less than 3 time the weight necessary to balance the weight of the load on the projecting part of the needle when the platform is fully loaded. Are properly secured to the needle Are of purpose made metal or similar approved material Have their weight clearly stamped thereon Page 27 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS c) Purpose Made Scaffold Tube Overhead Supports Scaffold tube needle supports may take the form of a spurred needle arrangement or a double needle arrangement as show in figure 10. They are to be counterbalanced as in figure 10 or tied to the building or structure capable of withstanding three times the force likely to be imposed. d) Structural Members of the Building or Structure Provided an Engineer’s evaluation has approved the use of structural members of the building or structure as overhead supports, it is acceptable to do so. e) Inspection Prior to Use Prior to any light duty suspended stage being put into service for the first time or being put into service after a substantial period of non use, the light duty suspended stage shall be inspected and tested by a SAS Accident Prevention Advisor. f) Load Calculation In order to have the correct counterweight inclusive of the safety factor, it is necessary for the scaffolder to be able to calculate the load outboard. The load shall be calculated in the following manner: SWL of the platform + Mass of the platform + Mass of winches + Mass of wire and cables = Total suspended load + 25% allowance for shock load = Total outboard load the total outboard load is divided by two to determine the outboard load per needle. f) Winches There are numerous climbing winches available, each with their own special features. Prior to any climbing winch being put into service on prior approval must be obtained. Features common to all climbing winches approved for use on site are: Drive up, drive down SWL clearly displayed Dead man button operation Manual operation in the event of power failure Automatic fall stop rope Page 28 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS g) Winch Ropes Winch ropes are supplied with winches by the manufacturer and under no circumstances should be substituted for any other rope. The ropes are generally 8mm diameter, 6/24 or 6/31 steel core construction galvanized steel. All the safety features of the climbing winch are to no avail should the rope break so the correct handling and inspection of the rope are critical. The following procedures shall be observed to ensure the correct handling, storage and inspection; I) Store in a coil of approximately 400mm diameter tied at quarter points with twine. II) Store in an area free from moisture. III) A rope register shall be kept in which regular rope inspections shall be logged. IV) The operator of the light duty suspended stage should observe the rope when ascending or descending and report to his supervisor, any signs of wear, broken wires, kinks or bird caging. V) When suspended from overhead supports, the rope shall be anchored to remain taut and any excess coiled up. VI) Ropes stores in coils shall be rolled out rather than pulled from the middle as this will cause the rope to kink and ultimately birdcage. h) General Safety All personnel required to work from the platform of a light duty suspended stage shall wear at all times, approved anti-fall protection secured to the guard rail. The area shall be barricaded with general purpose bunting and a sign displayed prominently stating “Danger – Men Working Above”. 9 INSPECTION SCAFFOLDING CONSTRUCTION (SC) shall ensure that, at all time of handing over, the scaffold iii) iii) iii) iii) iii) iii) Complies with any design drawing and /or specification for that particular scaffold Complies with the requirements of statutory regulations and British Standard Is adequate for the purpose of which it is intended Is stable and in safe condition Is marked to indicate its Safe Working Load mentioned in SCAFFTAG Has been thoroughly inspected by competent person Page 29 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS iv) The Hand-over Certificate has been signed and dated on behalf of SCAFFOLDING CONSTRUCTION (SC) v) The scaffold must be inspected prior to dismantling. If the scaffold is defective, it must be made good before dismantling commences. Where alterations have been made to the scaffold during its working life. It is not safe to assume that dismantling can be carried out in sequence the reverse of that used during erection. 10 SCAFFTAG System SCAFFTAG’s allow an immediate visual indication of the condition of a scaffold structure. The system comprises: • A holder which fits over a scaffold tube and displays “DO NOT USE SCAFFOLD” in red on a white background. Insert for the holder, one side white on green to indicate, when showing, that the scaffold is certified for use and giving details, the other side black on yellow to indicate, when showing, that the scaffold is under inspection and must not be used. An exact duplicate of the insert is retained in a SCAFFTAG rack in an appropriate location, e.g. Authorities Office, Control Room, etc. • NOTE: The only person authorized to fix or change a SCAFFTAG is a Scaffold Inspector appointed by SCAFFOLDING CONSTRUCTION (SC). Removal of a SCAFFTAG may be carried out by the Performing Authority where he is of the opinion that a scaffold is unsuitable for its intended application, in which case he shall remove the insert to display the “ DO NOT USE SCAFFOLD “ message and request VIC and/or Inspector to rectify/recertify the scaffold. A SCAFFTAG may also be removed by any person inform his supervisor for remedial to be taken. The client may remove any SCAFFTAG if he deems that area unsafe to work any other reason not attributed to the scaffold its self i. e. Gas Leeks area, Steam cleaning etc. 11 MODIFICATIONS Modifications to SCAFFTAG- certified scaffolds shall be undertaken only by SCAFFOLDING CONSTRUCTION (SC) with the authority of the worksite supervisor. After a modification has been made, inspection and recertification shall be carried out. If unauthorized modifications are observed, they shall be reported to be worksite supervisor and the insert removed from the SCAFFTAG holder to reveal the “DO NOT USE SCAFFOLD” warning. Page 30 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS 12 HAZARDS DURING SCAFFOLDS CONSTRUCTION, USE AND DISMANTLING OF All procedures and safety guidelines followed shall take into consideration the following hazards. iii) iii) iii) iii) iii) iii) iii) iii) Faulty structural design or inadequate bracing Faulty materials of construction Overloading Deterioration of fixing or the materials of construction due to damage or the weather Unauthorized alteration Impact from passing vehicles Failure of the scaffold structure when incomplete Scaffolding materials being dropped during handling 13 SAFETY SIGNS AND BARRIERS Whenever a scaffold is incomplete, during construction, alteration or dismantling all access points must be barrier and marked by warning signs and notices to indicate that scaffold is not safe for general use. The access area around a scaffold may need to be roped-off, to reduce the risk of debris or equipment falling on passer-by. 14 PRECAUTIONS DURING CONSTRUCTION AND DISMANTLING All materials must be raised or lowered in an orderly manner, by hand or by hoist. Small items should be handled in secured bags or baskets. No items may be thrown or allowed to fall. No scaffolder shall work without a secure foothold and a secure handhold. iii) iii) Properly secured ladders shall be used for access to heights. No scaffolder shall work from a scaffold platform of less than three scaffold boards all properly supported. Page 31 of 32 METHOD STATEMENT GENERAL PROJECT SCAFFOLDING WORKS iii) iii) The method of work employed shall avoid unnecessary exposure of scaffloders at heights. For exposed work at heights, scaffolders shall wear safety harnesses and whenever practicable, attach safety lanyards to a secure anchor point on an adjacent structure. 15 REQUEST TO ERECT AND DISMANTLE BY USERS / CLIENT – LEVEL OF URGENCY i) iii) v) Level 1: Level 2: Level 3: Level 4: Level 5: Required in one week’s time of later ii) Required in three days time Required within one to two days iv) Required in a half a day Required immediately 16 COMPETENCE AND TRAINING iii) Persons employed to erect, inspect, alter or dismantle scaffolds must be competent and experienced scaffolders. Scaffolding Supervisors and Foremen must be qualified from a suitable scaffolding qualification courses and must be experienced in work with scaffolds. Training shall be provided by SCAFFOLDING CONSTRUCTION (SC) Training Center that provides training for scaffolders (tubes and fittings) based on British Standards. iii) iii) Page 32 of 32


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