Safety - Anchor Points

What makes me qualified to tell you about fall prevention and protection?

I have been a Chartered Engineer for about 14 years and have over 20 years experience of working in a variety of industrial environments that have all included working at height. These include Petrochem, Metal Manufacturing, Power Generation and Construction.

In that time I have promoted safe working at height to everybody.

For a number of years I was employed by a large American Corporation and was deemed to be the local Fall Prevention and Protection expert and introduced many new systems and methods of work.

I am now in a position where I would like to share some of the knowledge I have gained over the years.

1. All permanent anchor points used for fall arrest purposes should be certified as to their reliability to arrest a fall of 6 feet or less. A permanent anchor point is defined as a single eye-bolt, hook, beam trolley, or other loading device continually affixed to a capable structure and utilized repeatedly during normal production operations or during periodic maintenance operations which may continue for weeks, months, or years.

2. Certification of permanent anchor points is the responsibility of the facility where the anchor is located. Certification must be done by a "Competent Person" who may be defined as one capable of making a decision as to the reliability of an anchor system to arrest a fall of 6 feet or less. While calculations are not required to certify every anchor point, the "Competent Person" must have the technical knowledge to prepare calculations for any anchor point that he (she) certifies. More specifically, if the individual requested to certify an anchor point does not have the expertise to prepare calculations representing system forces (shear, moment, torque), member actual and allowable stresses, and system deflections, then the individual cannot be considered a "Competent Person" for the anchor point in question.

3. Certification of a permanent anchor point includes certifying the adequacy of the structural system to which the anchor is attached. The structural system is defined as all structural elements necessary to provide a load path of resistance to the applied force(s).

4. Certification of a permanent anchor point for which calculations have not been prepared requires that the "Competent Person" document his (her) determination of adequacy in writing. In this regard a temporary anchor point is not necessarily adequate to be certified as a permanent anchor point due to the difference in types of connectors. Connectors which are normally used to create permanent anchor points can cause eccentricity on the supporting structural member and thus initiate an unacceptable overstress condition.

5. Each certified permanent anchor point should have a tag affixed which states the following: (1) identification as an anchor point, (2) an identification number, and (3) the number of persons that may be properly attached to the anchor point. If the latter is not specified, then only one person may attach to the anchor. Each permanent anchor point shall be re-certified at three year intervals.

6. A temporary anchor point may be used in lieu of a permanent anchor point. A temporary anchor point is defined as a location on a support member to which a connecting device is attached for a short time period. When the current, specific need is over, the temporary anchor point is then eliminated by removing the attachment. Thus, anchor points used by workers engaged in construction activities are normally considered temporary, not permanent. However, temporary anchor points may also be used for routine production and maintenance activities as well. Beam and column clamps as well as cross arm straps and chains, wire hooks and hook anchors are to be used as temporary anchors.

7. Certification of temporary anchor points is the responsibility of the construction contractor or production/maintenance organization. Temporary anchors may be certified by a "Competent Person" within the organization. Structural members used as temporary anchor points need not be certified if they are deemed to be of sufficient size and strength as per established guidelines. All other anchors including horizontal lifelines, eye-bolts, hooks, or other loading devices should be certified by written documentation or calculations.

8. If a production area, construction contractor, or maintenance organization does not employ a "Competent Person", then a qualified consultant may be contacted directly.

1. A temporary anchor point is defined as a location on a support member to which a connecting device, which does not require welding or bolting, is attached for a short time period, such as during the construction phase of a project. Such devices include beam and column clamps, cross arm straps, beam trolleys, wire hooks and hook anchors. When the current, specific need is over, the connecting device is removed.

2. A support member used as a temporary anchor must be made of steel in good condition and can be a wide flange section, round pipe, or rectangular structural tube. It may be a beam (horizontal geometric orientation), or column (vertical geometric orientation).

3. A support member used as a temporary anchor should be at an elevation such that the attachment point of the lanyard to the anchor is at the height of the harness rear D-ring or higher in order to limit a potential fall distance to 6 feet or less. Likewise, the height of the attachment point of the lanyard to the anchor must be 16 feet or more above the floor or ground to provide sufficient distance to eliminate striking the floor or ground if a fall occurs.

4. A temporary anchor as outlined below is assumed to have the capability to support only one individual falling 6 feet or less. If more than one individual is required to tie off to the same support member, then the acceptable member length (span) must be reduced by dividing the calculated member length by the number of individuals to be attached. Thus, a 24 foot long support member that is deemed acceptable for tie-off by one individual, must be no longer than 12 feet for two individuals, 8 feet for three individuals, and 6 feet for four individuals. Under no circumstances must more than one lanyard be attached to a connecting device.

5. When used as a temporary anchor, an existing steel wide flange beam supporting one individual must conform to the following parameters:

· Flanges must be parallel to the ground (web is vertical)
· Minimum flange width = 6 inches
· Minimum member depth = 6 inches
· Maximum member length (span in feet) = sum of flange width + member depth (inches)
· Each end of the beam must be connected to another steel member with a minimum of four, ¾ inch diameter structural steel bolts

· EXAMPLE #1: A 10 inch deep beam having an 8 inch flange width can span 18 feet.
· EXAMPLE #2: A 12 inch deep beam having a 6 inch flange width can span 18 feet.
· EXAMPLE #3: An 8 inch deep beam having a 6 inch flange width can span 14 feet.

6. When used as a temporary anchor, a round steel pipe beam supporting one individual must conform to the following parameters:

· Minimum pipe size = 6 inch diameter
· Maximum member length (span in feet) = 2 times the pipe diameter (inches)
· Each end of the beam must be connected to another steel member with a minimum of four, ¾ inch diameter structural steel bolts

· EXAMPLE #4: A 6 inch diameter pipe can span 12 feet.
· EXAMPLE #5: A 10 inch diameter pipe can span 20 feet.

7. When used as a temporary anchor, a structural steel tubing beam (also known as box beam) supporting one individual must conform to the following parameters:

· Minimum size of square tubing = 6 inches
· Minimum size of rectangular tubing = 6 inches for the least side dimension
· Maximum member length (span in feet) = sum of two adjacent member sides (inches)
· Each end of the beam must be connected to another steel member with a minimum of four, ¾ inch diameter structural steel bolts

· EXAMPLE #6: Tubing with all sides measuring 7 inches can span 14 feet.
· EXAMPLE #7: Tubing with adjacent sides measuring 10 inches and 6 inches can span 16 feet.
· EXAMPLE #8: Tubing with adjacent sides measuring 12 inches and 4 inches is unacceptable since the least dimension is less than 6 inches.

8. Anchorage devices attached to a wide flange beam support member shall be of a type that will not induce torsion (twist due to a load applied eccentric to the member web) on the member. Devices such as cross arm straps, beam trolleys, and beam clamps are acceptable. Devices such as D-bolt anchors, push-through eye bolts, mounted D-rings and brackets may induce torsion depending upon the attachment location. Use of these latter devices shall be approved by a "Competent Person".

9. A beam support member used as an anchor should not directly or indirectly support other significant live loads while it is being used as an anchor. Live loads may include, but are not limited to, stationary and moving equipment, heavy tools, stored materials, vehicles, people, water or snow.

10. When used as a temporary anchor, a steel wide flange column, a round steel pipe column, or a structural steel tubing column must be of adequate strength. All high bay building wide flange columns and crane columns are acceptable provided that they are in good condition, are not free standing in any direction, and are at least 10 inches deep with 8 inch wide flanges. All pipe columns are acceptable provided that they are in good condition, are not free standing in any direction , and are at least 10 inches in diameter. All structural steel tubing columns are acceptable provided that they are in good condition, are not free standing in any direction, and are at least 10 inches square (10 inches per side).

11. Welded tubular and piping guard post systems embedded in the floor are suitable as temporary anchor points provided that they are in sound condition and are a minimum of 8 inches wide on each side or 8 inches in diameter, respectively.

12. Members unsuitable for use as anchor supports unless certified by a "Competent Person" include the following:

All structural or other members in all pre-engineered buildings (i.e. Butler-type)
Lifting eyes on gear boxes, motors, valve handles, stems, etc.
Handrails, ladders, and ladder cages
Electrical conduit, cable trays and cable ladders
C-clamps
Ductwork
Roofing, siding, or other sheet metal
Process piping supported by pipe hangers and having mechanical joints
Horizontal cables
Structural steel members such as channels, tees, angles, and round and square bars
Other structural steel members that do not meet the criteria listed in this policy

13. Materials unsuitable for use as anchor supports unless certified by a "Competent Person" include the following:

Aluminum
Wood
Most brittle materials including cast iron, plastic, glass, masonry, and ceramics.

14. Hooks or other adequate structural elements of mobile cranes and overhead traveling cranes may, under special circumstances, be certified as temporary anchor points. However, such uses shall be identified (along with appropriate LOTO procedures ) in a JSA, Job Safety and Health Plan, or other safety procedure which has been approved by management and safety representative(s).

The information in this lens is provided for information only and does not intend to replace any training that a user must receive. The author can accept no responsibility of any kind for any accident, injury, damage or loss resulting from a person or persons using this information.
This information must not be used to replace local standards, procedures and training.

Every job must be fully assessed for risk and method before any works are performed.