SAFETY IN SCAFFOLDING

Introduction

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Every year nearly 100 fatalities and 10,000 injuries occur world over on scaffolds despite numerous safety regulations aimed to prevent such incidents.  If you work on scaffolding, you must be able to recognize the hazards associated with the type of scaffold you are using, and know what to do when you recognize something that just isn’t safe.  There are a number of different scaffold types, having different rules and regulations surrounding their assembly, fall protection requirements, and inspection procedures

TYPES OF SCAFFOLDS

There are 30 different types of scaffolds being used in Construction Industries all over the world. But the most commonly used scaffolds used all over the world are given in diagrams attached to this portion of the material. In India, the use is limited to few numbers, like welded frame scaffold, bamboo/wooden scaffold, pole scaffold and Mobile scaffold.

SAFE WORKING--- MAKING YOUR WAY

Working with scaffolding requires your employees to be attentive to their actions and the task at hand. To work safely, there are numerous safety rules and regulations they should follow. The following rules are generally accepted practices. When reviewing with employees, add any rules that are specific to your operations as well as common sense rules you have learned through your experiences.

1.     Design

Footings: Scaffolding footing or anchorage must be sound and capable of carrying the maximum load without settling. Do not use unstable objects such as barrels, boxes, loose brick or concrete blocks to support scaffolds or planks. Do not erect, move, alter or dismantle

Guardrails: Guardrails made of lumber must not be less than 50x100 mm (or other material providing equivalent protection). They must also be between 900 mm and 1200 mm high, with a midriff of 25x150 mm lumber (or other material providing equivalent protection), and have a minimum 150 mm high toe boards on all open sides and ends on scaffolds more than 3000 mm above the ground or floor. Supports must be at intervals that do not exceed 2000 mm. Ramps and walkways 1500 mm above lower levels must have guardrail systems.

 Where persons are exposed to falling objects and are required to work or pass under the scaffold, there must be a screen between the platform and the guardrail. It must extend along the entire opening, and support a downward or horizontal force of a minimum 70 Kgf (35 Kgf on a single point and two-point adjustable suspension scaffolds). The screen's openings should be small enough (not to exceed 150 mm) to prevent passage of potential falling objects.

Planking: All planking of platforms must be overlapped (minimum of 300 mm), or be secured from movement. Scaffold planks must extend over their end supports not less than 150 mm or more than 300 mm unless secured or blocked by a guardrail. Planks must be laid with their edges close together so the platform will be tight with no spaces greater than 25 mm through which tools or fragments of material can fall. Platforms more than 350 mm from the work surface must have a guardrail system and/or employees must use personal fall arrest system (for plastering and lathing = 450 mm). 

Work areas must be fully planked from the front uprights to the guardrail supports. All planking must conform to the minimum requirements of IS: 3696—1987 (pt-I)

Access: An access ladder or equivalent conforming to the requirement of IS 3696—1987 (Pt-II) to obtain a safe access must be provided. Rungs must be a minimum 200 mm wide (integral prefabricated frames) and uniform distance between rungs not greater than 300 mm. Cross braces are not acceptable for scaffold access.

Support & Stability: Scaffolds and their components must be capable of supporting without failure at least four times the maximum intended load. Wire, synthetic or fiber rope used for scaffold suspension must be capable of supporting at least six times the rated load. The poles, legs, or uprights of scaffolds must be plumb and securely braced to prevent swaying and displacement. Scaffolds must be tied back vertically at a height beginning at four times the scaffold width and then at a maximum every 8 meters. (Scaffolds 1 meter. and wider). The horizontal distance of the ties is not to exceed 10 meters.

Plumb : When the first tier of scaffold has been erected it should be checked for plumb, alignment, and level. Where necessary, adjustments can be made using the screw jacks.  Settlement or slight variations in the fit of the components may require additional adjustments as tiers are added to the scaffold tower. Braces should fit easily if the scaffold tower is level. If braces do not fit easily it is an indication that the scaffold is out of plumb or out of alignment.

Safe Clearance from Electrical Power Lines: The setting of the scaffold near an unprotected current-carrying wires or equipment, or insulated wires and equipment shall be started only when the lines are disconnected. After the erection of the scaffold, the wires may be made to carry current only when sufficient safety measures are taken. Please see Table-2 for maintaining safe clearance.

General : Employees must not work on scaffolds during storms or high winds. Slippery conditions on scaffolds must be eliminated as soon as possible after they occur. Any scaffold, including accessories such as braces, brackets, trusses, screw legs, ladders, etc., damaged or weakened from any cause must be immediately repaired or replaced. Overhead protection must be provided for employees on a scaffold exposed to overhead hazards. The use of shore or lean-to scaffolds is prohibited. Materials being hoisted onto a scaffold must have a tagline. Tools, materials, and debris must not be allowed to accumulate in quantities to cause a hazard.

2.     Inspection

Scaffold materials should be inspected before use for

• Damage to structural components
• Damage to hooks on manufactured platforms
• Splits, knots, and dry rot in planks
• Delaminating in laminated veneer lumber planks
• Presence of all necessary components for the job
• Compatibility of components.

Structural components, which are bent, damaged, or severely rusted, should not be used. Similarly, platforms with damaged hooks should not be used until properly repaired. Planks showing damage should be discarded and removed from the site so that they cannot be used for platform material. Factors. Generally, running sills longitudinally because the sill has more contact with the ground will increase bearing capacity.

3.     Use

Base Plates: Base plates and adjustable screw jacks should be used whether the scaffold is outside on rough ground or indoors on a smooth level surface. Base plates should be centered on the width of the sill and nailed securely after the first tier has been erected. Sills may run either across the width or along the length of the scaffold depending on grade conditions and other

Tie-ins: Scaffolds must be tied into a structure or otherwise stabilized—in accordance with manufacturer’s instructions and the Construction Regulation—as erection progresses. Leaving such items as tie-ins or positive connections until the scaffold is completely erected will not save time if it results in an accident or injury. Moreover, in most jurisdictions, it is prohibited.

Fall Protection in Scaffold Erection: Providing practical fall protection for workers erecting and dismantling scaffold and shoring has been challenging for the construction industry. Workers erecting, using, or dismantling scaffolds must be protected from falling by using guardrails, travel restraint, fall-restricting systems, or fall-arrest systems. For fall protection while workers are using a scaffold as a work platform, the safest solution is guardrails, provided they can be erected safely. Workers involved in erecting or dismantling scaffolds face a different challenge. Erecting guardrails and using fall-arrest equipment requires specialized procedures since normally there is nothing above the erector on which to anchor the fall protection system.

Recognizing that development and innovation continue in this field, we are offering a sampling of fall protection techniques (fall prevention and fall arrest) in the figure below. These generic examples allow individual employers, trade groups, unions, and others to adapt the guidelines to their site-specific needs and to trigger further development.

 Fall Protection while working in scaffold

Training : Training must be provided by a person qualified in the subject matter and hazards associated with the scaffolding being used. A. Training must be given to employees performing the work informing them of:

• Electrical hazards
• Proper scaffold use

·         Load capacities

Training must be given to employees involved in erecting, disassembly and inspection by a competent person informing them of:

• Hazards
• Correct procedures
• Loading capacities

You must retrain employees because of:

• Changes in the worksite
• Changes in the equipment
• Lack of proficiency