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Sreenivasa Hassan Jayaram
Manager-Projects, Jones Lang LaSalle India, Bangalore, Karnataka
1. Anchorages – An anchorage is a secure point of attachment for lifelines, lanyards or deceleration devices. Anchorages used for the purpose of fall arrest shall be capable of supporting at least 5,000 pounds (22.2 kN) per employee attached. Alternatively, a fall protection system may be designed, installed, and used as part of a complete personal fall arrest system which maintains a safety factor of at least two, under the supervision of a Qualified Person (certified anchor). Both are considered acceptable for fall protection so long as they meet the general requirements and the performance criteria specified for their type. General requirements for all fall arrest anchorages include:
i. Located as high as possible to minimize the free fall distance to and arresting forces to < 1800 pounds. (8kN).
ii. Located to prevent contact with obstructions or the ground below.
iii. Located directly over the working position whenever possible to minimize swing falls.
1.1 Non-certified Anchor – Non-certified anchors are those where the specific strength is unknown but can be judged by an Competent Person to limit potential free fall to 6 feet (1.8m) or less and be capable of supporting at least 5,000 pounds (22.2 kN) per employee attached. Examples of non-certified anchors include I-beams or structural members of a building.
1.2 Certified Anchors – Certified anchors areanchors which are engineered. They are anchors installed for the specific purpose of arresting a fall as a component of a personal fall arrest system (PFAS). Certified anchors shall be designed, installed and used as a part of a complete personal fall arrest system which maintains a safety factor of at least two, under the supervision of a Qualified Person.
i. Only Qualified Persons shall design certified anchorage points and horizontal lifeline systems.
ii. Sites shall not allow the use of a certified fall arrest anchor point by employees unless it is known that the anchor point is capable of supporting at least 5,000 pounds (22.2 kN) per employee attached or is designed, installed, and used as part of a complete personal fall arrest system which
maintains a safety factor of at least two, under the supervision of a Qualified Person.
iii. As with personal fall arrest systems certified anchors shall be inspected before use and in accordance with manufacturer’s criteria.
iv. Certified anchors subject to impact loading or damage due to arresting a fall, natural disaster or any other event that could leave the anchor structurally unsound shall be removed from service until inspected by a competent or qualified person and determined to be safe for reuse.
v. Certified anchors shall be used exclusively for the purpose of fall arrest. Under the following circumstances certified fall arrest anchors may require additional identification or marking specifying their usage exclusively as an anchorage point;
a. where there are anchor points that are at risk of being used for purposes other than fall arrest such as hoisting,
b. where fall arrest anchors have unique performance criteria or limitations that may not be obvious to a user such as, an anchor that supports more than one employee or an anchor that requires limited arresting forces, or
c. where the intended purpose of a fall arrest anchor is unclear, such as due to similar looking systems in the vicinity which are not approved for the purpose of fall arrest.
NOTE: Training, site orientation, or operational and maintenance procedures on anchorage points restrictions and usage is an acceptable method in-lieu of marking
The following table describes minimum strength requirements for both certified and non-certified anchors. Anchor strength values given below are minimum static strength requirements for one attached employee. For multiple-employee systems, multiply the minimum strength values below times the number of personnel connected to the anchor.
|Type||Non-certified anchorage requirements as determined by a Competent Person||Certified anchorage requirements validated by a Qualified Person.|
|Fall Arrest||5,000lbs. (22.2 kN)||2 x Maximum Arresting force|
|Work Positioning||3,000lbs. (13.3 kN)||2 x foreseeable force|
|Fall Restraint||3,000lbs. (13.3 kN)||2 x foreseeable force|
|Horizontal Lifeline||Not Applicable||2 x maximum line load|
|Rescue||3,000lbs. (13.3 kN)||5 x applied load|
Note: A fall arrest system that correctly uses a shock absorber and is anchored well overhead will exhibit arresting forces between ~900 pounds (4kN) for a self-retracting lanyard or ~ 1350 pounds (6kN) for a 6’ (1.8m) lanyard.
2. Horizontal Life Line (HLL) – A HLLis an anchor system that incorporatesa flexible line that spans horizontally between two end anchorages. This system offers employees freedom of horizontal movement.
i. HLL’s shall be designed by a Qualified Person.
ii. Snaphooks shall attach to a HLL connector rather than directly to the HLL.
iii. Post install testing of HLL lifelines and anchors prior to use is recommended.
3. Connectors – Connectors are used tocouple connecting parts of a personal fall arrest system together. Compatibility of each connection in the personal fall arrest system shall be evaluated to prevent the risk of unintentional “roll out” due to compression on the snap hook gates.
4. Full Body Harness – A full body harness is a body support devicedesigned to safely distribute the impact forces of a fall through the employee’s body.
i. Choose the style/type that best serves its intended use and fits the employee best.
ii. A D-ring extension is sometimes used to assist employees in more easily reaching D-rings for tie- off. The extension length shall be taken into account when assessing an employee’s total free fall distance.
5. Ladder Safety System – A Ladder Safety System is a fall protection system for fixed ladders. A ladder safety system uses a fall arrester on a vertical cable or track attached to a fixed ladder. This system travels up and down the ladder with the employee by connecting to the full
body harness front D-ring.
i. Ladder safety systems shall not to be used for work positioning.
ii. Ladder safety devices may be used on tower, water tank, and chimney ladders over 20 feet (6m) in unbroken length in lieu of cage protection. No landing platform is required in these cases.
iii. The centerline of the carrier and the point of attachment to the full body harness shall be no greater than 9 inches (23cm).
iv. All ladder safety devices shall be maintained in accordance with manufacturer requirements.
6. Lanyard – Lanyard is used for connecting the full body harness to a deceleration device, lifeline, or anchor. There are a number of different lanyard types. Understanding their function and limitations is necessary.Lanyard general requirements include:
i. Lanyards shall have double-locking snap hooks.
ii. The length of a single lanyard shall not exceed 6 feet (1.8m) unless designed by the manufacturer and used in accordance with its intended purpose.
iii. All lanyards used for the purpose of fall arrest shall be equipped with a shock absorber or have a deceleration component which limits maximum deceleration distance an employee travels to 3.5 feet (1.07 m).
iv. Lanyards shall have a minimum breaking strength of 5,000 pounds (22.2kN).
6.1 Adjustable lanyards – Adjustable lanyard is a lanyard with hardware that allows the employee to adjust the total lanyard length. Adjustable lanyards are often useful for fall restraint applications
6.2 Y-lanyards – Y-lanyard is a specially designed lanyard that is shaped like a Y with one connection point for the employee and two lanyards for connecting to anchors. This configuration enables an employee to maintain connection while transferring between anchorages, thereby maintaining continuous (100%) fall protection.
i. Two snap hooks shouldn’t be connected to the same anchorage.
ii. The unused end of a Y–lanyard should not be connected to a spare D-ring on the full body harness (such as the hip D-ring). Doing so will create double arrest forces and potentially side loading during a fall.
7. Self-Retracting Lifeline (SRL) – AnSRL is a deceleration device containing a drum-wound line which adjusts in and out during normal employee movement. During a fall, the drum locks and arrests the fall. When used appropriately, SRL’s reduce free fall distance, total clearance needed, and maximum arresting forces. The following are SRL general use requirements:
i. In cases where an SRL is mounted high overhead, a means to access the snap hook will be provided that doesn’t require the SRL snap hook and line to be left in an extended position (i.e. a tag line, resource to pull the line down).
ii. Care should be taken to reduce swing in the event of a fall by working ask close to the anchor point as possible. See manufacturer guidance on working distance from the SLR to reduce swing fall.
iii. SRL’s shall not be used with horizontal life lines unless specifically designed for that type of use.
8. Snaphook– A snap hook is a connecting hardware component which automatically locks in the closed position.
i. Snaphooks shall be a locking type designed and used to prevent disengagement of the snaphook by the contact of the keeper by the connected member.
ii. Snaphooks shall not be engaged to any object which is incompatibly shaped or dimensioned in
relation to the snaphook such that unintentional disengagement could occur by the connected object being able to depress the snaphook keeper and release itself.
iii. All snaphooksunless designed for shall never connect directly to:
a. Webbing, rope or wire rope,
b. Another snap hook
c. A D-ring to which another snap hook or other connector is attached
d. A horizontal lifeline
9. Vertical lifelines (VLL) – A VLL is anchored overhead and used in conjunction with a fall arrester that travels along the rope and is attached to the employee. VLL’s are typically used as a fall arrest system when travel along long vertical lengths are required.
i. VLLs are only designed for use by one employee at a time.
ii. Maximum length of a VLL is 300 feet (91.4m), as the weight of rope can affect the rope/rope grab connection.
iii. Ropes are to be weighted at the bottom to keep slack out of the line.
iv. Rope stretch shall be taken into consideration in evaluation of the total fall clearance calculation.
v. VLL’s shall never carry any additional load such as tools or work platforms.
10. Fall Arrester (rope grab) – A Rope Grab Fall Arrestor is a device which travels vertically along a VLL to provide an anchorage which can be adjusted to be just above the height at which an employee is working. A Fall Arrestor may be either Manual or Automatic. In the event of a fall, the arrestor shall lock onto the rope arresting the fall in 1 -2 feet (.3 to .6m). There are two types of fall arrestors:
Automatic arrestors: do not requiring any manual assistance to move vertically on the VLL.
Manual arrestors: do require manual assistance by the user to open and close the locking mechanism to facilitate movement up and down the VLL.
General fall arrestor use requirements include:
i. Ensure that the rope and arrestor are compatible.
ii. Use care to orient the arrestor in the correct direction. See the manufacturer’s instructions for clarification.
iii. Fall arrestors should always be positioned as high above the employee as possible to reduce free fall distance.
Reference and Acknowledgement
 Fall Protection Program by OSHA guidelines http://www.oshatrain.org
 Working At Height Guidelines, Version II, 21st September 2011 http://www.mic.ul.ie/adminservices/policies
We at engineeringcivil.com are thankful to Sir Sreenivasa Hassan Jayaram for submitting this paper to us.
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