Although life safety rope and accessory cord look similar, there are some very important difference in both their construction and their use. This differences determine how to use them safely.
Ropes used for supporting a human load, also known as life safety rope, such as for use in rope access and rope rescue must be designed for that purpose. There are two main standards in use that cover this type of rope. They are:
- EN 1891:1998 – Personal protective equipment for the prevention of falls from a height – Low stretch kernmantel ropes
- NFPA 2500:2022 – Standard for Operations and Training for Technical Search and Rescue Incidents and Life Safety Rope and Equipment for Emergency Services
The details and testing procedures of these standards are different but they specify:
- Kernmantle construction (an outer sheath and an inner core)
- Minimum breaking strength
- Minimum melting point
Both EN 1891 and NFPA 2500 also require the entire length of the rope to be manufactured from continuous fibers. Splices or joins of fibers within the rope are not allowed.
These requirements are in place to ensure the ropes are suitable for the intended life safety use.
Although they look similar, the performance of rope and accessory cord is very different.
What is Accessory Cord?
Accessory cords are smaller diameter ropes, between 4mm and 8mm, which are used for auxiliary purposes such as creating friction hitches, anchors, and slings. Unlike life safety ropes, accessory cord standards such as EN 564 only require a static minimum breaking strength test. Minimum melting temperatures, dynamic ‘shock’ loads, elongation, and other qualities are not tested.
Because the testing requirements for accessory cord only require testing of the static minimum breaking strength, the outer protective sheath of accessory cord is thinner than on life safety rope and provides less protection from abrasion caused by sharp or rough surfaces.
The specification details of accessory cords without certification is dependant on the information provided by the manufacturer. It is up to the users experience to determine if the chosen accessory cord application is suitable. Accessory cords should never be used as an alternative for life safety rope without fully understanding the risks involved.
Polyamide (nylon) and polyester accessory cord has very low abrasion resistance
Can I use Accessory Cord for rappelling?
The simple answer is accessory cord is not certified for this type of use and should only be used this way in an emergency.
A major safety concern with the use of ropes isn’t the overall strength but the potential of the rope to be cut while in use. This problem has typically been resolved by the use of larger diameter ropes. Larger diameter ropes contain more material which makes the ropes more resiliant to friction and contact with edges. For example, an 8mm rope only has 40% of the material as a 12mm rope.
As the rope diameter becomes smaller, the proper rigging of the rope becomes more important. More care must be given to how the rope is being used and potential problems with edges become a greater concern. A small rope should not just be used in place of a larger rope without completely understanding the additional risks created.
What should I use for smaller diameter rope?
NFPA 2500 (1983) includes a category of ropes defined as escape rope. Escape rope has the same design requirements as life safety rope including the requirement to be constructed from continuous fibers and a minimum melting point not less than 204C. The major difference is the smaller diameter (7.5 – 9.5mm) and a lower minimum breaking strength (13.5 kN).
NFPA 2500 (2022) states the following about escape rope
A.126.96.36.199 Rope used for emergency egress is defined as a single purpose rope. During actual use, the integrity of the rope can be assumed to be compromised, and the rope should be taken out of service and destroyed. Such rope generally is left behind at the scene of the incident, and the degree of exposure to heat and flame is unknown and probably will have substantial damage.
When used in a training context, escape rope should be inspected in the same manner as life safety rope.
Are there other small diameter ropes that I can use?
Some ropes are specially designed for outdoor sporting use where they are subject to abrasion from sandstone and other rough surfaces. Commonly known as canyoneering ropes, they are also widely used for tactical use where a lighter weight rope is needed do to their increased durability.
While they might be mistaken for accessory cord, the technology used in their construction is very different. These ropes are specially designed for this purpose and are made from modern fibers such as technora which make them much more abrasion resistant than normal nylon or polyester ropes.
These ropes are typically 8-9.5mm in diameter but have a much higher abrasion resistance than smaller diameter life safety ropes or accessory cord. Because they are designed for extreme conditions, canyoneering ropes are usually stiffer and have less elongation than normal life safety ropes. This results in a stiffer rope but with better durability.
NOTE: Canyoneering ropes are not usually certified to either NFPA 2500 or EN 1891 because the advanced fibers and construction techniques used fall outside of these two standards. When choosing a canyoneering rope, the reputation of the manufacturer is paramount.
Before purchasing a rope for rappelling, rescue, or access use, we recommed first determining how the rope will be used and what characteristics are desired. An appropriate rope can then be chosen to ensure the rope is compatible with other equipment being used and also to safely perform the activity.