Working At Height

WORKING AT HEIGHT 

Work where there is a risk of a fall liable to cause personal injury unless precautions are taken.  

Hazards: 

1. Slip, trip, fall 
2. Collapse of scaffolding  

3. Improper access and egress 

4. Falling from height 
5. Falling objects 
6. Flying objects 
7. Manual Handling 
8. Overhead Live lines 
9. Vehicle 
10. Ergonomics 
11. Working beneath the scaffolding 
12. Heat stress 
13. Adverse weather  
14. Transportation of material 

Scaffolding Work Control Measures: 

1. Ensure all access/egress routes are kept clean at all times, to maintain work area Clean during  and end of  work.
2. Provide Barricades and Signage. 
3. Maintain good housekeeping to avoid the  slip, trip, and fall. 

4. Use full body harness with double lanyard and maintain 100% tie-off. 
5. Secure all the materials and tools. 
6. Only competent person can doing the scaffolding works (Erection, Modification and Dismantling). Close supervision should be required. Good communication should  be established among the crew. 
7. Follow Manual handling procedure. 
8. Maintain distance from overhead power lines. 
9. Do not allow anybody to work beneath   the scaffolding work. 
10. Do not exceed the maximum load. 

11. Drink plenty of water, take rest in shaded area (resting shelter), take regular intervals, and follow the client procedure.
12. Do not allow any body to work due to adverse weather like heavy wind. Stop the activity and wait for the further client instruction. 

• Overlapping of two adjacent planks in a platform should not less than 12 inches 
• Scaffold platform and access should be at least 18 inches wide.  
• Any gap on scaffolding platform should not be greater than 1 inch.  
• Minimum height of a toe-board is 6 inches. 
• The height of top-rail is 42 inches plus minus 3 inches.
• Mid rail should be 21 inches high.  
• The distance between guardrails and toe boards shall not exceed 765 mm. 
• Standard boards are nominally 225mm wide and 37mm thick, but 50mm and  63mm are available.  
• Boards shall not be painted or treated in any way, which shall conceal defects in them. The end of all scaffold boards shall be bound and protected by metal hoops  
• Ladder must be at correct angle of 75 degrees (1:4)  
• Ladder must be 3 feet above the platform for safe landing.  
• The base width to height ratio of scaffold is 1:4. For example if base width is 2 m, the maximum height would be 8 m.
• Each scaffold and scaffold components must support without failure its own weight and at least  4 times the maximum intended load applied to it. (Suspended scaffold must support its own weight and at least 6 times of intended load). 
• PFAS should be used when working at height at 1.8m. 
• Strength of the scaffolding /Loading Capacity depends upon the vice versa of ledger size. Greater the size of ledger lesser the loading capacity.
• Length of Harness lanyard as per OSHA is 6ft and Maximum Arresting Force of harness is 1,800 lbs. (13 KN) and capacity is: 130 lbs. - 310 lbs. (59 kg - 141 kg). 
• Work at height should be stopped at 17 knots 
• Ladders shall be placed inside a scaffold wherever possible, and landing places shall be provided vertical intervals of no more than 9.0 meter.
• There is no maximum height for using a ladder. However, where a ladder rises 9 meters or more above its base, landing areas or rest platforms should be provided at suitable intervals 
• Chin strap for Helmet is compulsory when High windy times & Working at height. 

Types of Fall Protective System: 

1. Guardrail system (e.g. Edge protection) 
2. Safety net system  
3. Lifeline 
4. Personal Fall arrest system (e.g. full body harness, lifeline)  safety Net system.

Inspection of Safety Harness 

Webbing check 

• Hold the harness up by the shoulder straps and ensure that the webbing hangs evenly 
• Connect buckles and ensure harness is not distorted and hangs correctly 
• Check webbing for signs of UV damage 
• Check webbing for signs of chemical damage (staining is a good indication of chemical damage and can be identified if the harness appears brittle or hardened) 
• Check the condition of the webbing by running through thumb and forefinger 
• In all cases software, must be free from: -

- Cuts

- Fraying 
- Excessive abrasion 

• If you encounter any problems or you are unsure that your harness fits to the standard defined above, replace it.
• It is worth noting that proper care and cleaning of a fall arrest harness is just as important as the inspection it self.
• Cuts, nicks or tears 
• Broken fibers/cracks
• Overall deterioration                  
• Webbing thickness uneven 
• Missing Straps 
• Excessive hardness or brittleness (Indicates  heat or UV damage) 
• Stitching check 
• Pulled stitches 
• Stitching that is missing 
• Hard or shiny spots(Indicates heat damage)
• Hardware Check 
• Distortion (twists, bends) 
• Rough or sharp edges 
• Rust or corrosion 
• Cracks or breaks 
• Broken/distorted grommets 
• Modification by users 
• Discoloration

Tags or Labels 

• Check tag for date of manufacture and  remove from service if past adopted service life policy 
• If tagging system is missing or not legible remove harness from service. 
• Don’t Use Safety Harness 
• If the D ring, plastic back plate, fasteners, web tidies, adjusters or connectors do not look 
• right (check the 'Hardware inspection' question for details). 
• If the webbing does not look right (check  the 'Webbing inspection'question for details). 
• If you cannot find an inspection date recorded within the last 12 months. 
• If you cannot find a manufacturing date. 
• If you do not have an individual searial number. 
• Vertical lifelines and lanyards must have a minimum breaking strength of 5,000 pounds.
• Self-retracting lifelines and lanyards that automatically limit free fall distance to 2 feet or less must be capable of sustaining a minimum tensile load of 3,000 pounds applied to the device with the lifeline or lanyard in the fully extended position.

Scaffolding:

A temporary structure which is used to provide access, support material or plant or from which person works.     

Components of Scaffolds 

•  Base plate- 150*150*50mm 
•  Sill board 
•  Screw Jack 
•  Standards 
•  Ledgers 
•  Transoms 
•  Bracings 
•  Couplers 
•  Platforms 
•  Toe Boards 
•  Hand rails 
•  Mid rails 
•  Ladder 

Typical Scaffold Components 
Include: 

• Sole plate- first component of scaffold putted on ground to distribute the load. 
• Base plate/jack- in which the standard or vertical tube is fitted. it provides stability to scaffold. 
• Standard- the vertical scaffold poles that bear weight of the scaffolding. 
• Coupler- a fitting used to join components together. 
• Plank/board- they are used to make working platform. 
• Mid rails & guardrails- the scaffolding tubes fixed to the edges of scaffold to prevent fall of persons. 
• Toe boards- they are planks or boards fitted to the edges to prevent material fall. 
• Braces- they are scaffold tubes fitted  diagonally or horizontally to provide strength to the scaffold. 
• Transoms- a horizontal cross-section load-bearing component which holds the boards or decking unit. 
• Ledgers-a horizontal brace attached 90 degree to the transoms. 
• Ladder- used to get access to the scaffold.
• Gin Wheel - a simple form of tackle block,having one wheel, over which a pulley rope runs. The device is used to lift or lower lightweight properly secured materials and/ or object. 
• Kicker Lift / Foot Tie: The vertical distances measured from ground to the center of first ledger, normally this distance is 150 mm from ground and provided when scaffold is more than 6.0M height or scaffold carrying heavy load.
• Lift Height: The vertical distance measured between centers of two ledgers. Normal lift height is 2.2 Mo 
• Base lift or First Lift : is the first lift  above ground level, other than foot tie or kicker lift. 
• Base lift or First Lift : is the first lift above ground level, other than foot tie or kicker lift.

Standards: 

•  Scaffold: BS 5973:1993 
•  Scaffolding Clamps: EN74. 
•  Put log: BS1139. 
•  Scaffolding Plank: BS 2482. 
•  Tube: BS1139, EN39  

Types of Scaffolds: 

•  Independent Scaffold. 
•  Bird-Cage Scaffold.  
•  Mobile Scaffold. 
•  Tube and Coupler scaffolding 
•  Bridge Scaffold 
•  Hanging Scaffolds 

Based on Load Capacity: 

• Very light duty- 75 kg/m2- 2.7m Bay length 
• Light duty- 150 kg/m2- 2.4m 
• Medium duty- 200 kg/m2- 2.1m 
• Heavy duty- 250 kg/m2 - 1.8m 
• Special purpose- 300+ kg/m2 
• Types of Safety Tags: 
• Tag is a paper system that is put on a  scaffolding indicating the present condition of scaffolding.  
• Red Tag: Do not use 
• Yellow Tag: being erected (can use with 100% fall protection)  
• Green Tag : Safe to use 

Details  Scaffold Tag: 

• Location  
• Max Loading Capacity (kg/m²)  
• Date of erection 
• Inspection date 
• Name and signature of certified Scaffolding Supervisor 

Inspection of Scaffolding: 

•  After Erection completed 
•  Before the start of work 
•  Every 7 days 
•  Any Alteration done 
•  Extreme weather conditions 

Types of Lanyard: 

•  Shock-absorbing lanyards 
•  Self-retracting lanyards (or SRLS)  
•  Positioning lanyards.

Types of couplers:

Types of baracing:

Ladder Terminology: 

Beam, Bed section, Heel, Shoes, Fly sections, Pads, Hooks & rungs; 

Types of Ladders 

•  Straight ladder. 
•  Step ladder. 
•  Extension ladder. 
•  Roof/ Hook ladder. 
•  Folding ladder. 

Ladder Hazards: 

• Fall from height- falling of ladders, toppling of ladders to sideways, ladder base slipping out from the wall. 
• Falling of Objects. 
• Over reach
• Contact with overhead lines. 

Ladder Control Measures: 

• Do not handle the ladder near overhead lines. 
• Site on a solid, flat base, weight should only be supported on the styles, never on the rungs. 
• Angle of the ladder should be 75 degree to the horizontal or at a ratio 1:4 distance away from the wall to height.
• Do not over reach from the ladder. 
• Top of the ladder must be 1 meter (am3  rungs) from the landing and secured properly. 
• The base should also be secured or be footed by someone standing on the bottom rungs. 
• Face the ladder when ascending or descending. 
• Maintain 3 point contact on the ladder 

Rescue Procedure for Working at Heights 

Emergency Planning 

The three main parts of emergency planing are: 

1. Creating a training and testing plan 

2. Creating an emergency plan 

3. Outlining rescue procedures. 

Emergency Response Plan 

worker falls and is suspended by a safety harness, implement the emergency response plan by following the steps below Note: It’s important for everyone to know their role. 

1. The site supervisor (or alternate foreperson) takes control of the situation. 

2. The site supervisor sounds the emergency alarm—two long blasts from a horn. All workers in the immediate vicinity of the incident stop working.  

3. The site supervisor or their designate  goes to get help if workers are close by. If no one is close enough, the site supervisor calls for help.  

4. The site supervisor calls to notify local police fire,and ambulance if required. 

5. The crane operator remains on standby.  

6. The site supervisor (or a worker assigned to the task) isolates the accident zone and its perimeter to limit further exposure.

7. The site supervisor(or a worker assigned to the task) moves all non-affected personal to a safe zone or directs them to remain where they are.  

8. The site supervisor enables radio silence on the jobsite, except for crisis communications from emergency responders. These communications are  conducted on a pre-selected "emergency  only" radio channel. 

9. The site supervisor sends a designated worker to the site gate to meet the response team (police, medical, fire, etc.) and ensure that they have a safe access path to the accident scene. 

10. The site supervisor assembles the emergency rescue team at the accident site as quickly as possible to determine the best rescue procedure for the situation. 

Rescue Procedures 

The following rescue procedures are  ordered (A) through (D), with (A) being the preferred method and (D) being the method used when there is no other means of rescue. 

A. Elevating Work Platform Rescue—If an elevating work platform (EWP) is available on site and the suspended worker can be reached by the platform, follow the procedure below. 

1. Bring the EWP to the accident site and use it to reach the suspended worker.   

2. Ensure that rescue workers are wearing full-body harnesses attached to appropriate anchors in the EWP.  

3. Ensure that the EWP has sufficient load capacity for both the rescuer(s) and the victim. 

4. If the victim is not conscious, two rescuers will be needed to safely handle the weight of the victim. 

5.When the worker is safely on the EWP, reattach the lanyard to an appropriate anchor point on the EWP, if possible.

6. Lower the worker and arrange for treatment of the victim for suspension  trauma and any other injuries. 

7. Arrange for transport to nearest hospital.

B. Ladder Rescue—if an elevating work platform is not available, use ladders to rescue the fallen worker with the procedure outlined below. 

• Where possible, use ladder(s) to reach the victim. 
• Rig separate lifelines and fall arrest equipment for rescuers to use while assessing the victim from the ladder(s). 
• If victim is not conscious or cannot reliably help with their own rescue, at least two rescuers will be needed. 
• If victim is suspended from a lifeline, move them to an area that can be safely reached by the ladder(s), 

where possible. 

• If victim is suspended directly from their lanyard or from a lifeline, securely attach a separate lowering line to the victim’s harness. Other rescuers will lower the victim while being guided by the rescuer on the ladder. 
• In no case should ladders be used to support the weight of more than one worker. 
• Once the victim has been brought to a safe location, administer First Aid and treat the person for suspension trauma and any other injuries. 
• Arrange for transport to nearest hospital. 

C.  Rescue from Work Area or Floor Below—If the fallen worker is suspended near a work area and can be safely reached from the area from which they fell or the floor below, use the following procedure: 

• Ensure that rescuers are protected against falling. 
• If possible, securely attach a second line to the workers’ harnesses to assist in pulling them to a safe area. 
• (Note: more than two strong workers will be needed to pull a victim upwards for rescue.) 
• Ensure that any slack in the retrieving lines is taken up to avoid slippage. 
• Once the victim has been brought to a safe location, administer First Aid and treat the person for suspension trauma and any other injuries.  
• Arrange for transport to the nearest hospital. 

D.  Basket Rescue—if a worker has fallen and is suspended in an inaccessible area, you may need to perform a basket rescue.  

For basket rescues, the basket must be designed by a professional engineer and constructed in accordance with good manufacturing processes to withstand all loads to which it may be subjected. It must be kept on site at all times in an accessible location where it is clear of material or other equipment. Fit the rescue basket with a double connection to the crane and appropriate rigging for quick hookup by the crane operator.

Always keep the following items in the rescue basket.  

1.  First-aid kit 

2.  Three lanyards equipped with shock absorbers 

3.  One full-body harness 

4.  Tag line attached to the basket at all times.

5.  Descent controller rescue device in good working condition 

6.  Secondary safety line to tie the basket above the headache ball of the crane. 

To perform a basket rescue, follow the steps below. 

1. Make sure preferred methods A, B, and C are not possible. 

2. Notify the crane operator immediately to position the crane to attach the basket. 

3. While the basket is being attached, the crew leader checks that all safety rigging is done and all the required safety equipment is available. 

4. With two rescuers in the basket, hoist it to a position that is above and as close as possible to the fallen worker. A designated worker on the ground guides the basket with a tag line. The designated worker must make sure that when the rescue basket reaches the right elevation, the door of the basket is facing the structural steel to provide an easy exit for rescuer #1. 

5. Rescuer #1 exits the rescue basket and gets into a position to reach the fallen worker. When doing this, rescuer #1 must be tied-off at all times to either the structure or the rescue basket.

6. Rescuer #2, who is still in the rescue basket, lowers the line that will be used to retrieve the worker. Rescuer #2 attaches an extra lanyard to the line if required. 

7. Rescuer #1 assesses the fallen worker for injuries and then decides how to proceed (i.e., treat injuries first, guide the fallen worker into the rescue basket, or lower the basket to the ground with the fallen worker attached to it). 

8. Once the fallen worker has been brought to a safe location, administer first aid. Treat the person for suspension trauma and any other injury.  

9. Arrange transportation to hospital. A designated worker must accompany the injured worker to hospital. If the basket rescue is the method used, keep the following points in mind. 

• Perform a basket rescue only when it is not possible to use conventional equipment to rescue fluent the worker in a safe manner.
• Never exceed the maximum number of workers in the basket as indicated on the nameplate. 
• Ensure that a competent worker inspects the crane and equipment being used prior to lifting rescuers. 
• Always equip the crane with a fail-safe mechanism to prevent the boom from descending in the event of a power source or system failure. 
• Maintain an adequate means of communication between the rescuers in the basket and the crane operator at all times.
• Ensure that workers in the rescue basket wear full-body safety harnesses attached to a lanyard and anchored to appropriate points in the basket at all times.  
• Make sure that all rigging used to attach the rescue basket to the hook of a load line has a safety factor of 10 against failure. There should be a safety line attached to the load line directly from the  Do not allow cranes to travel while rescuers are in the basket. Do not use suspended rescue baskets during high winds, electrical storms, snow, ice, sleet, or other adverse conditions that could affect the safety of personnel on the platform or in the basket.