Generic HEIGHT SAFETY IN FORMWORK 16/11/2012. Built from basic generic components like planks, beams, and posts of timber, steel etc.

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1 Traditional using scaffold material HEIGHT SAFETY IN FORMWORK By James Tay System formwork TOKA FORMWORK Table form Generic Built from basic generic components like planks, beams, and posts of timber, steel etc. 1

2 Modular Put together from standard components such as tubes/rolled sections of fixed dimensions & shapes. WAH Contraventions Improper Access & Work platform All Rights Reserved 2

3 Improper Formwork Shoring Unsecured Falsework lead to collapse of shoring Lack of Barricade Stairs Formwork with Landing 3

4 Poor knowledge of Fall Prevention WAH System Contraventions Application Improper / no work platform No Proper Work platform provided below the formwork for job on level alignment and sealing of gaps. OR Work platform provided but not secured, and there was no proper access. The luminous level of these areas were usually low when fully covered. Worker could not have a clear vision of their path. 4

5 Unsafe / No Barricades Improper Access Table Form Table designed originally for horizontal slabs, but modified to accommodate T and L beam and slab combinations A single set of forms may be used repeatedly from floor to floor Table Formwork 5

6 Opening between Table Form Most of the time, openings between table form can be cross over easily are seem as safe. But it s also big enough for a person to fall through. Improper Access to Table Form During transferring, worker take risk climbing up to release the slinging. 6

7 Improper placing of Table Form The the table form was not set up in according to design of the Professional Engineer 1. The formwork Subcontractor claimed Space constraint 2. The front props for the table form could not be set up according to PE design 3. PE was not asked to redesign to suit the site situation System A ready-made collection of members and connections of various patented proprietary designs, with capacity tables, and assembly instruction manuals, with which the entire falsework structure can be speedily and efficiently erected. Suitable for repetitive use of standard or fixed complex configurations 7

8 Improper Placing / transferring When a section of the formwork was lifted away, the remaining formwork collapsed and toppled onto a worker. He subsequently died from his injuries. Improper secure 1. Connecting brackets between internal and external formwork panels 2. Deceased was standing around this on the working platform of the formwork panel prior to the incident. 3. The formwork panel had peeled off exposing the concrete wall 4. The deceased fall 6m to the first level. The formwork panel also came down and landed on him. 8

9 Improper access / egress There was no access / egress installed. The deceased climb the scaffold to dismantle the metal formwork and fall to dead Climbing Formwork System Commonly used for multistoreyed structures, particularly for prismatic vertical components such as columns, walls and lift cores. 9

10 A Collective of Fall Prevention System 16/11/2012 What can cause a workmen to fall in a Formwork job scope? 1. Failure of fall prevent planning. a) No proper access or egress b) No proper work platform c) Substandard lifeline d) Improper installation of lifelines e) Improper use of PPE f) Improper guarding 2. Failure to follow SWPs a) Improper position of task b) Unstable of table form structure due to improper placing / installation / transferring. c) Poor maintenance that lead to the collapse of formwork structure d) Improper installation of formwork system not in according to PE design e) Failure to secure Designing a Safe Work Approach Design a safe work Method Can Work Restraint be applied? Is Fall Arrest method the last choice? Where is the anchorage point? Selection of Fall Protection System Hard Barricades Type of Work Platform Method of Access Selection of Fall Prevention Equipment Vertical or Horizontal Lifeline? Who & How the anchorages are installed? Can Safety Net or Air Bag be used? 10

11 Design a safe work Method Work Restraint - anchor away from fall hazard Anchor away from open edge Anchor at Horizontal Lifeline installed between permanent structure Wall Working on Scaffold 11

12 Design a safe work Method Fall Arrest System- anchor high to reduce shocking load Anchor low at feet level Anchor high above head level It :- Require 6m height clearance Experience High fall factor Likely to induce shocking load to max (2.2T) if it did not have shock absorber It :- Experience Low fall factor Likely to induce low shocking load that will not deploy the shock absorber Has a good chance to climb back to platform Selection of Fall Protection System 12

13 Proper Access & Work Platform Scaffold access Horizontal Lifeline 13

14 Horizontal Lifeline Bowline 26% Double figure of eight 23% Sub standard Tied knots - %? Horizontal Lifeline Sub-standard sling strength? Can it arrest a fall? Proper sling setup only retain 75% - 80% design strength 14

15 Horizontal Lifeline Anchorage strength required is 3 x Body Mass (100kg) Anchorage strength required is 1 x person Kg 2 x person kg 3 x person kg Horizontal Lifeline installed as work restraint anchorage. Horizontal Lifeline installed at edge served as fall arrest anchorage. Horizontal Lifeline Anchor at Horizontal Lifeline installed between permanent structure 15

16 Summary Good Planning Risk Assessment & Fall Prevention Plan Installing an Effective Collective Fall Prevention System Training to enhance a competent workforce Thank You! 16