Prevent Falls with OSHA’s 3 Lines of Defense
Before you begin a fall protection program, identify all potential hazards. Any time a worker is at a height, there is risk.
Before you begin a fall protection program, first identify the potential fall hazards in your workplace. Any time a worker is at a height, there is a risk of falling. Generally, the greater the height, the greater the risk is of sustaining a more severe injury.
OSHA’s Three Lines of Defense
To help control the risk of falling, following the Occupational Safety and Health Administration’s (OSHA’s) “three lines of defense” philosophy is suggested.
The first line of OSHA fall protection defense is to eliminate and/or engineer fall protection equipment in order to eliminate fall hazard risk. Engineering/elimination controls can be as simple as moving the work to ground level and eliminating the work height. Or they can mean the addition of platforms, railings and toe boards to provide permanent, secure access to high maintenance areas and devices. The number of engineering controls is extensive; contact your plant engineering or maintenance department for further assistance.
When engineering/elimination controls are not feasible or practical, the second and third lines of defense can be used to help control the fall hazard. The second line of defense is administrative controls, such as employee training or written programs and policies. The third and last line of defense to be considered is personal protective equipment (PPE). Examples of PPE fall into three basic categories.
Three Basic PPE Categories
- Positioning: Devices that hold a worker in place while allowing hands-free work. These devices must limit free fall to less than two feet. Positioning is comprised of four basic components:
a. Anchor point: Certified (evaluated by a qualified person) two times the foreseeable force; Non-certified (selected by a competent person) tested to 3000-pound (lb.) load
b. Body wear: Full-body harness and/or belt
c. Connecting device: Rebar chain assembly
d. Fall arrest backup: Shock-absorbing lanyard or self-retracting lifeline (SRL)
- Restraint: Devices used to limit the worker from reaching an unprotected edge or other fall hazard. This is accomplished by limiting the length of the connector. Restraint is comprised of three basic components:
a. Anchor point: Certified (evaluated by a qualified person) two times the foreseeable force; Non-certified (selected by a competent person) tested to 1000-lb. load
b. Body wear: Full-body harness and/or belt
c. Connecting device: Fixed-length lanyard
- Personal Fall Arrest System (PFAS): Devices used to help safely absorb the energy produced in a fall event. Applies to any free fall from an elevated position of four feet or more in general industry or six feet or more in construction. A PFAS is comprised of three basic components:
a. Anchor point: Certified (evaluated by a qualified person) two times the maximum arresting force (1800 lb.); Non-certified (selected by a competent person) tested to 5000-lb. load
b. Body wear: Full-body harness only
c. Connecting device: Shock-absorbing lanyard or SRL
Harnesses and Belts
Full-body harnesses wrap around the waist, shoulders and legs (see Figures A, B and C). A D-ring located in the center of the back between the shoulder blades when properly adjusted is the fall arrest connection point. In the event of a fall, a full-body harness distributes the force of the impact throughout the trunk of the body, not just in the abdominal area. This allows the pelvis and shoulders to help absorb the shock, reducing the impact to the abdominal area. Full-body harnesses come with optional side, front and shoulder D-rings. Side and front D-rings are connection points used for work positioning only. Shoulder D-rings are for retrieval from confined spaces.
Three factors determine the arresting force from a fall: lanyard material type, free fall distance and the weight of the worker. The use of a shock-absorbing lanyard or a higher tie-off point can help reduce the impact force.
Body belts with a D-ring located on the rear waist are for travel restraint and hip D-rings are for positioning applications.
Connection devices attach the belt or harness to the tie-off point. This can be one device, such as a shock-absorbing lanyard, restraint lanyard or SRL, or a combination of devices, such as work lines, rope grabs, tie-off straps, and carabiners.
Shock-absorbing lanyards can be used both to restrain workers in position and to arrest falls. When using a restraint lanyard, the length should be kept as short as possible and never used for any vertical free fall hazard application. Restraint lanyards are available in a variety of materials, including steel cables, nylon rope, nylon webbing and polyester webbing. Shock-absorbing lanyards (see Figures A and C) can be made of steel, nylon rope, nylon webbing or Dacron® webbing.
All shock-absorbing lanyards incorporate a “shock pack” that will deploy to absorb the energy produced during a fall event. The “shock pack” must reduce the potential fall arrest force to less than 1800 lbs. Use of a shock-absorbing lanyard is recommended because it typically limits the arresting force from a six-foot drop to less than 900 lbs. A shock-absorbing lanyard used for a fall is limited to allow a maximum six-foot free fall. For this reason, most lanyards are a maximum of six feet long. However, if a higher tie-off point is used, the shock-absorbing lanyard can be longer as long as the free fall distance does not exceed six feet.
Lifelines add versatility to the fall arrest system. When used in conjunction with rope grabs (see Figure C), a lifeline allows the worker to move along the length of the line rather than having to disconnect and re-connect to a new tie-off point. The rope grab is engineered to help arrest a fall instantly. A rope grab and lifeline system is a passive form of protection, allowing the user to move as long as tension is slack on the lifeline. If a fall occurs, the tension on the rope grab triggers the internal mechanism to arrest the fall. An SRL (see Figure B) automatically retracts any slack line between the worker and the tie-off point. While this type of line doesn’t require a rope grab, it must be kept directly above the worker to help eliminate any potential swing hazard if the worker falls.
A cross-arm strap (see Figure A) is used at a tie-off point with a large diameter, such as an I-beam. The cross-arm strap then provides the anchor to which a shock-absorbing lanyard, restraint lanyard or SRL can directly attach. Using a cross-arm strap helps ensure the lanyards and/or lifelines do not become abraded or twisted from wrapping around the I-beam. A carabiner (see Figure D) works in the same situations. It is used for tie-off points with a diameter of one to five inches, and then the lanyard is attached to the carabiner.
A tie-off point (see Figures A, B, C and D) is where the shock-absorbing lanyard or SRL is attached to a structural support. When shock-absorbing lanyards or an SRL are being used, ensuring that the anchor point is at or above the D-ring point of the harness will minimize the free distance. This also helps ensure that the shock-absorbing lanyard or SRL doesn’t interfere with personal movement. Workers must also tie off in a manner that ensures no lower level will be struck during a fall. To calculate this when using a shock-absorbing lanyard, add the height of the worker, the shock-absorbing lanyard length, the stated elongation distance listed on the device and a safety factor of three feet. To calculate when using a SRL, add the height of the worker, the maximum free fall distance of two feet, the maximum deceleration distance of three and one-half feet, and a safety factor of three feet. The sum of these distances should not be greater than the distance measured from the work surface the worker is standing on to the next level or object below that any part of their body could strike if they fell.
For confined space applications, a tripod and winch system is used as both the tie-off point and connection device. It is used in conjunction with a full-body harness to lower and raise workers into tanks or manholes. Make sure that the tripod system you choose is designed for your application. Never use a material handling device for personnel use unless it is specifically designed to do so.
Ladder systems are lifelines attached directly to a fixed ladder. The systems consist of a cable or channel, with a grabbing device attached for a connection point.
- Tie-off point
- Rope grab
- Shock-absorbing lanyard
- Cross-arm strap
- Retractable lifeline
- Full-body harness
- Restraining belt
- Restraining lanyard
Any fall rescue program should be as safe as possible and must take as little time as possible to bring a fallen worker to safety. When a fall occurs, any number of factors can create challenges to the effective rescue of the victim. Weather conditions, physical obstacles and the condition of the victim can consume time and create hindrances for rescue personnel.
All rescue plans should be regularly reviewed to ensure the procedures are manageable and realistic in their time estimates. Employers should act in their own best interests by implementing the safest and quickest rescue plan and by practicing procedures to maximize preparation for a real emergency.
OSHA recommends these general rescue plan guidelines:
- Rescue suspended workers as quickly as possible
- Be aware of the potentially life-threatening risks of orthostatic intolerance and suspension trauma
- Be aware of signs and symptoms of orthostatic intolerance
- Be aware that suspended workers who are unconscious or have head injuries are particularly at risk for orthostatic intolerance
- Be aware of the factors that can increase the risk of suspension trauma
- Be aware that some authorities advise against moving the rescued workers to a horizontal position too quickly
For more information on the OSHA bulletin on orthostatic intolerance and rescue, visit: www.osha.gov/dts/shib/shib032404.html.
To help alleviate the potential for orthostatic intolerance for a conscious suspended worker, the use of trauma straps can provide comfort and relieve pressure, which improves blood circulation until rescuers arrive. Straps are designed to work with most brands of harnesses; adding a second device provides better support and balance for the fallen worker.
Inspection and Maintenance
OSHA regulations require that all fall arrest equipment be inspected prior to its use. This includes looking for frays or broken strands in lanyards, belts and lifelines, and oxidation or distortion of any metal connection devices. To properly maintain the devices, periodic cleaning is necessary. Clean all surfaces with a mild detergent soap, and always let the equipment air dry away from excess heat. ANSI Z359.11-2014 suggests at a minimum to comply with all manufacturer instructions regarding the inspection, maintenance and storage of the fall protection equipment.
IMPORTANT NOTE: ANY EQUIPMENT EXPOSED TO A FALL MUST BE TAKEN OUT OF SERVICE AND NOT USED.
29 CFR 1910 Subpart F, Powered Platforms, Manlifts, and Vehicle-Mounted Platforms
29 CFR 1910 Subpart D, Walking-Working Surfaces
29 CFR 1926 Subpart M, Floor and Wall Openings
29 CFR 1926 Subpart X, Stairways and Ladders
29 CFR 1926.104, Safety Belts, Lifelines and Lanyards
29 CFR 1926.105, Safety Nets
29 CFR 1926.451, Scaffolds General Requirements
ANSI/ASSE A10.4-2016 Safety Requirements for Personnel Hoists on Construction and Demolition Sites
ANSI/ASSE Z359.11-2014 Safety Requirements for Full-Body Harnesses