Metal Scaffolding Safety. Henry Tho LAM and Alexander C.S. CHAN. Industrial Centre The Hong Kong Polytechnic University Hong Kong

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1 Metal Scaffolding Safety Henry Tho LAM and Alexander C.S. CHAN Industrial Centre The Hong Kong Polytechnic University Hong Kong 1.0 ABSTRACT Safety is a basic human need. To achieve zero accidents is a common goal that every body would like to see. However it is not easy to attain it and we still have much to work towards it. In fact, construction safety can be further developed and continually improved by providing adequate and practical training to the relevant workers of the contractors. This paper is aimed at not only introducing the relevant regulations and the code of practice for scaffolding safety, but also describing how the metal scaffolding training program was developed by the Industrial Centre of The Hong Kong Polytechnic University to meet such requirements and industry needs. A Typical Example of Metal Scaffolding Work in Hong Kong 289

2 2.0 INTRODUCTION In view of the current trend of Hong Kong construction industry, not only the safety regulations and codes of practice but also the practical training programs are necessary to enhance the degree of safety awareness. The statistics made by Labour Department on the occupational injuries in all workplaces in 1998 (analyzed by major economic activity) indicate that construction industry has the highest injury accident figure (31%) and fatal accident (29%) as shown in Table 1. Major Economic Activity No. of Injuries % of Total of Injuries No. of Deaths Agriculture and Fishing % 2 0.8% Mining and Quarrying % 1 0.4% % of Total of Deaths Manufacturing % % Electricity and Gas % 1 0.4% Construction % % Wholesale & Retail Trades, Restaurants and Hotels Transport & Related Services, Storage and Communication Financing, Insurance, real Estate and Business Services % % % % % % Community, Social & Personal Services % % Activities not adequately defined % 0 0% TOTAL % % Table 1 - Occupational Injuries in All Workplaces, 1998 As far as the type of accident in construction industry is concerned, it can be seen that most of the fatal accidents mainly came from fall of person from height (55%) and struck by falling object (16%) as shown in Fig. 1. Further analysis does show that fall of person is mainly caused by metal scaffolding work. The main reason for this is because there were lots of the contractors who did not provide proper training and safe working procedures to their employees. To prevent the said accidents, a practical training together with a safe system of work with written procedures and guidelines for the metal scaffolding operation, should be devised and implemented along side with the regulations. 290

3 Industrial Fatal Accidents in Construction Industry Analyzed by Type of Accident, 1998 ( ) = the figure in bracket denotes the number of deaths Trapped by collapsing or overturning object 7% Striking against or struck by moving object 2% (1) (4) Struck by Struck by falling object moving vehicle 16% 5% (9) (3) Trapped in or between objects 4% (2) Striking against fixed or stationaey object 2% (1) Contact with electricity or electric discharge 9% (5) Fall of person from height 55% (31) Fig. 1 - Fatal Accidents in Construction Industry 1998 This paper aims to take a closer look at the safety of metal scaffolding with respect to the existing regulations, code of practice and the relevant training programs. Moreover, the curriculum of the metal scaffolding training course developed by the Industrial Centre of The Hong Kong Polytechnic University will also be discussed. 3.0 METAL SCAFFOLDING REGULATIONS Part VA of Construction Site (Safety) Regulations (Chapter 59I) of the Factories and Industrial Undertakings Ordinance in Scaffolds, Working Platforms and Ladders has been amended and enacted on 1st October The amended regulations identify the following issues: (i) (ii) (iii) (iv) safety scaffolding inspection, boatswain's chairs (not power operated), interstice of metal platforms, and intermediate guard-rail Appendix 1 and Appendix 2 show the details of the amended regulations. 291

4 To have a quick glance between the old and the amended regulations, a summary of their differences is shown in Table 2. Old Regulation 38K (1)(a)(i) Inspection of scaffolds The scaffold shall not be used on a construction site unless it has been inspected by a competent person within the immediately preceding month. 38I (1)(a) Boatswain's chairs (not power operated) The boatswain s chair or similar plant or equipment shall not be used unless it is of good construction, sound material, adequate strength and free from patent defect. 38L (a) Construction of working platforms, gangways, runs, etc, Every working platform, gangway or run from which a person is liable to fall a distance of more than 2 metres shall be a platform consisting of open metal work having interstices none of which exceeds 3800 square mm in area. Code of Practice for Scaffolding Safety (d)(vii) Toe-boards and end toe-boards should be of such a height that the gap between the top of the toe-board and the guardrail does not exceed 700 mm. Amended Regulation 38F 1(a)(iv) Inspection of scaffolds The scaffold has been inspected by a competent person at regular intervals not exceeding 14 days immediately preceding each use of the scaffold. 38G Boatswain's chairs (not power operated) The contractor responsible for a construction site shall ensure that no boatswain s chair or similar plant or equipment is used on the site. Third schedule - Requirements with which certain safety equipment must comply 2(2)(a) Working platforms, consisting of open metal work having interstices none of which exceeds 4000 square mm in area. Third schedule - Requirements with which certain safety equipment must comply 6(b) The height of a guard-rail above any place of work on a working platform, gangway, run or stairway shall be in case of an intermediate guard-rail, not less than 450 mm and not more than 600 mm. (not for bamboo scaffold) Table 2 - Comparison between the old and amended regulations of Construction Site (Safety) Regulations. 4.0 METAL SCAFFOLDING TRAINING COURSE At present, there is no institution offering the specific metal scaffolding training course except the Industrial Centre, which developed the first course for construction companies in Since then, a total of twelve courses of about 300 participants (Site Agent, Engineer, Safety Officer, Safety Supervisor, General Foreman, Foreman and worker) has been conducted. The Course contents have been recently revised to meet the amended regulations. 292

5 The metal scaffolding training course consists of two different sessions: Lecture and Practice. Each session is a half-day duration and can be conducted in the Centre's workshop or at the construction site. The practical session aims to back up the lecture part. In the lecture session, the participants will be taught with the concept of metal scaffolding as well as the relevant regulations, code of practice, design principles and safety measures. In the practical session, the participants will practice the job skill by erecting the metal scaffold including how and where to tie in the scaffold throughout the whole process. Figures 2 and 3 show the course participants attending the lecture session and undertaking the skill training in the practical session respectively. A certificate in Metal Scaffolding Training will be issued to the trainees upon satisfactory completion of the course. Fig. 2 - Lecture Session Fig. 3 - Practical Training Session Moreover, the Job Safety Model developed by the authors will be introduced to the participants as well, so that they can realize the importance of risk assessment before carrying out any work 4.1 Job Safety Model The Job Safety Model aims to prevent the job-related accidents is emphasized in this training course. Figure 4 shows the general principles of the model as explained below: 293

6 Risk assessment is a key factor for accident prevention. For any job to be done, risk assessment should be made with respect to: the person assigned to do the job, whether competent or not; the equipment necessary for the job, whether adequate and in good condition or not; the job environment (i.e. work place/site environment), whether safe or not; and the job steps (more specific analysis), what particular hazards associated with each job step. After such analysis, the risk control measures for the job can be developed. Then, the control measures should be integrated into the job steps to form the safe working procedures. Integration is important! It is through integration that people will not miss the safety steps. As stated by Petersen (1978), We do not want production and a safety program, or production and safety, or production with safety - but, we want safe production." This concept of 'integrated' safety should be recognized and implemented. Safe working procedures are the standard operation procedures for the job and must be implemented. Before implementation, it is essential that the person assigned to do the job must fully understand the procedures. In other words, job instruction including safety aspects must be given to the operator to ensure the know-how. Control cannot be exercised over any system unless its performance is monitored. Therefore, to ensure job safety, monitoring should be done through work supervision, and this should be the responsibility of the front-line supervisor. Safety is a line function, as said by Anton (1979) and Petersen (1978). As top management directs the effort by objective setting, planning, organizing and controlling, it assigns responsibility to line management people and grants them authority to accomplish results. The most important person for monitoring and ensuring safety at work is the front line supervisor. It is important in the sense that he/she deals most directly with the employees and thus bears the greatest responsibility for enforcing the company rules and procedures. To be successful, front line supervisors must be given the appropriate authority as well as adequate training in safety. If the supervisor when monitoring discovers some unsatisfactory condition such as unsafe performance/environment, or deviation from the laid down standards/procedures, it is essential for him/her to identify the causes of the problems by going through again the previous steps of the Model where appropriate, so that suitable actions can be taken. If necessary, the supervisor may seek advice from the safety experts. Also, if there is a change in the job elements such as change of the operator, equipment, environment or job steps, risk assessment should be made accordingly. 294

7 JOB TO BE DONE RISK ASSESSMENT - Operator - Equipment - Environment - Job steps STANDARD OPERATION Integrate PROCEDURES Integrate Risk control measures Job steps JOB INSTRUCTION to ensure the operator fully understands Unsatisfactory MONITORING Satisfactory SAFETY AT WORK Operator Equipment Environment 5.0 CONCLUSION Fig. 4 - Chan & Lam's Job Safety Model The accident rate concerning the scaffolding work in construction industry is very high. In this respect, the Labour Department has recently amended Part VA of the Construction Site (Safety) Regulations for the purpose of reducing accident occurrence and improving safety record. The authors believe the amended regulations can achieve the said purpose. To support the legislation, the Industrial Centre developed a metal scaffolding training course for construction industry in 1995, and since then a total of 12 training courses for 300 participants has been successfully completed. Job Safety Model developed by the authors is emphasized in the training course. The Model stresses on the importance of risk assessment, safe working procedures, job 295

8 instruction and safety monitoring. By emphasizing the Model to the trainees, their safety concept and safety awareness can be enhanced, and thus safety at work can be achieved. 6.0 REFERENCES Anton, T.J. 1979, Occupational Safety and Health Management, McGraw Hill Book Co., New York. Hong Kong Government 1999 Regulation of Factories and Industrial Undertakings Ordinance (Cap 59I), Construction Sites (Safety) Regulations, Hong Kong Government. Petersen, D. 1978, Techniques of Safety Management, 2 nd edn., McGraw Hill Book Co., New York. 296

9 APPENDIX 1 Chapter 59I, Construction Sites (Safety) Regulations Safety of places of work Part VA Scaffolds, Working Platforms and Ladders, etc. Inspection of scaffolds [Reg. 38F] 1. The contractor responsible for a scaffold on a construction site shall ensure that the scaffold is not used unless a) the scaffold i. has been inspected by a competent person before being taken into use for the first time. ii. has been inspected by a competent person after any substantial addition, partial dismantling or other alteration; iii. has been inspected by a competent person after any exposure to weather conditions likely to have affected its strength or stability or to have displaced any part of it; iv. has been inspected by a competent person at regular interval not exceeding 14 days immediately proceeding each use of the scaffold; and b) a report has been made and signed by the person carrying out the inspection in an approved form containing the prescribed particulars which include a statement to the effect that the scaffold is safe working order. 2. Paragraph (1) shall not apply in relation to a scaffold from no part of which a person is liable to fall from a height of 2 metres or more. 3. A report under paragraph (1) b of an inspection of a scaffold shall be delivered forthwith by at the competent person to the contractor responsible for the scaffold. 4. The contractor to whom a report is delivered under paragraph (3) shall a) at all time keep the report, or a copy thereof, on the construction site on which the scaffold to which the report relates is located; b) at all reasonable times make that report or copy available for inspection by i. any occupational safety officer who requests to see it; ii. any other person who is lawfully on the site (including any person using or proposing to use the scaffold). Boatswain's chairs (not power operated) [Reg. 38G] The contractor responsible for a construction site shall ensure that no boatswain's chairs or similar plant or equipment (not being a boatswain's chair or similar plant or equipment which is raised or lowered by a power-driven lifting appliance) is used on the site. 297

10 APPENDIX 2 Chapter 59I, Construction Sites (Safety) Regulations Schedule 3 Requirements with which certain safety equipment must comply Refer to regulation 38B(4) 1. Width of working platforms, gangways and runs 1. The width of any working platform, gangway or run shall be not less than 400 mm 2. The width of any working platform, gangway or run used for the movement of materials shall be not less than 650 mm. 3. Where it is impracticable by reason of limitations of space to provide a working platform, gangway or run of the width required by subsection (1) or (2), the, in lieu of complying with that subsection, the working platform, gangway or run shall be as wide as is reasonably practicable. 2. Working platforms, etc. to be closely boarded, etc. 1. Subject to subsection (2), every working platform, gangway and run shall be closely boarded or planked 2. Subsection (1) shall not apply to a working platform, gangway or run a) consisting of open metal work having interstices none of which exceeds 4,000 mm2 in area; or b) the boards or planks of which are so secured as to prevent their moving and so placed that the space between adjacent boards or planks does not exceed 25 mm. If there is no risk of persons below the platform, gangway or run being struck by materials or articles falling through the platform, gangway or run. 3. Boards and planks in working platforms, gangways and runs Every board or plank forming part of a working platform, gangway or run shall a) be of sound construction, adequate strength and free from patent defect; b) be of a thickness capable of affording adequate security having regard to the distance between the supports and be not less than 200 mm in width and not less than 25 mm in thickness or not less than 150 mm in width when the board or plank exceeds 50 mm in thickness; c) not protruding beyond its end support to a distance exceeding 150 mm unless it is sufficiently secured to prevent tipping; d) rest securely and evenly on its supports; and e) rest on at least 3 supports unless, taking into account the distance between the supports and the thickness of the board or plank the conditions are such as to prevent undue or unequal sagging. 4. Coverings for opening Every covering provided for an opening shall be a) so constructed as to prevent the fall of persons, materials and articles; and b) clearly and boldly market as to show its purpose or securely fixed in position. 5. Height of toe-boards The height of a toe-board or other similar barrier shall be not less than 200 mm. 6. Height of guard-rails 298

11 Subject to section 7, the height of a guardrail above any place of work on a working platform, gangway, run or stairway shall be a) in the case of a top guard-rail : not less than 900 mm and not more than 1,150 mm b) in the case of an intermediate guardrail: not less than 450 mm and not more than 600 mm. 7. Exception to section 6 Section 6 shall not apply to a working platform on a bamboo scaffold if the platform is protected by not less than 2 horizontal bamboo members of the scaffold spaced at intervals between 750 mm to 900 mm. 8. Temporary removal, etc of guardrails etc. (1) Guard-rails, toe-boards and barriers may be removed or remain unerected for the time and the extent necessary for the access of persons or the movement of materials or other purposes of the work concerned, but shall be replaced or erected as soon as practicable after the expiration of that time. (2) Toe-boards shall not be required for stairs. 299