SAFE USE GUIDELINES:

DIAMETER AND SIZE NUMBER VALUES:  Size is determined by linear density (weight); diameter is given as a nominal value, that is, it may vary slightly.  If a specific diameter value is required, linear density and minimum breaking strength values may be different from those given in tables.  Size number is given as a reference.

WORKING LOADS:  Minimum breaking strength is based on data from a number of manufacturers and represents a value of 2 standard deviations below the mean, as established by regression analysis.  The working load of a rope is determined by dividing the minimum breaking strength by the design factor.  Design factors range from 5:1 to 12:1 for normal service and modest dynamic loading, and should be higher for critical applications.

Because of the wide range of rope use, rope condition, exposure to the factors affecting rope behavior, and the degree of risk of like and property involved, it is not realistic to make standard recommendations as to design factors or working loads.  However, to provide guidelines, a range of design factors and working loads provided for rope in good condition with appropriate splices, in non-critical applications and under normal service conditions.  Normal service is generally considered to be used under static or very modest dynamic load conditions.

Design factors at the low end of the suggested range should only be selected with expert knowledge of conditions and professional estimate of risk, based on the critical conditions of use listed below.

Design factors at the high end of the range or larger shall be used when:

 1. Small ropes are used, because they can be more severely damaged by cutting, abrasion and sunlight.

 2. Loads are not accurately known.

 3. Operators are poorly trained.

 4. Operation/use procedures are not well defined and/or controlled.

 5. Inspection is infrequent.

 6. Abrasion, cutting, dirt are present.

 7. Shock loads or extreme dynamic loadings are likely.

 8. High temperatures are present.

 9. Chemicals are presents.

10. Ropes are kept in service indefinitely.

11. Tensions on the rope are maintained continuously for long periods.

12. Rope can be subject to sharp bends or is used over pulleys or surfaces with too small a radius.

13. Knots are used (strength is reduced by up to 50%).

14. Death, injury or loss of valuable property may result from failure.

For critical applications, a design factor greater than 12 may be necessary.  Users must determine the design factor as they are the only ones who can assess service conditions and establish operating procedures.  The load applied to the rope should not exceed the working load.  If uncertain, contact the rope manufacturer or a qualified engineering consultant for assistance.

IN ALL CASES WHERE ANY SUCH CONDITIONS ARE PRESENT, OR THERE IS ANY QUESTION ABOUT THE LOADS INVOLVED OR THE RISKS OF USE, THE WORKING LOAD SHOULD BE SUBSTANTIALLY REDUCED AND THE ROPE INSPECTED FREQUENTLY.

DYNAMIC LOADING:  Whenever a load is picked up, stopped, moved or swung, there is an increased force due to dynamic loading.  The more rapidly  or suddenly such actions occur, the greater the increase.  In extreme cases, the force put on the rope may be two, three or more times the normal load involved; for instance, when picking up a tow on a slack line or using a  rope to stop a falling object.  Therefore, in all such applications as towing lines, lifelines, safety lines, climbing ropes, etc., design factors must reflect the added risks involved.

Users should be aware that dynamic effects are greater on a low-elongation rope such as polyester and greater on a shorter rope than on a longer one.  The range of design factors given contains provision for very modest dynamic loads.  This means that the load must be handled slowly and smoothly to minimize dynamic effects.

SPECIAL SAFETY NOTE:  A dangerous situation occurs if personnel are in line with a rope under excessive tension.  Should the rope fail, it may recoil with considerable force - especially if the rope is nylon.  Death may result.  Persons must be warned against standing in line with the rope.

ATTENTION:  Specifications (physical properties) of all products are subject to change without notice.  Consult with factory for most recent information.