The Three Sigma Rating system is a method of Statistical Quality Control (SQC) used to describe, analyze and control the rated strengths of products developed by DMM. For each batch produced a statistically representative sample is taken and tested to destruction in accordance with either the relevant European Standard for that product and/or DMM's own approved internal Quality Assurance System. 3 Sigma Rating is a method of statistical Quality Control (SOC) and analysis which we use to control, monitor and describe the strengths of all our products, the basis of which is expressed by the following formula:

The UIAA (Union Internationale des Associations d'Alpinisme) began the process of formulating standards for Climbing and Mountaineering equipment over 3 decades ago. With the advent of the PPE ( Personal Protective Equipment Directive 89/686/EEC) in 1989 it appeared that UIAA standards no longer had any relevance, however the UIAA has continued to monitor and shadow EN standards and is currently formulating a standard for belay devices which will in due course be adopted as an EN standard.

It is because of this work, plus its global status that Mountaineering manufacturers have sought to reintroduce the UIAA label to its products. Therefore a product carrying the CE mark plus an additional UIAA label will have been tested to the most stringent international standards available.

In recent years the standards committees for the various member states of the European Union have been attempting to converge the standards and specifications for a wide range of applications. In the respect of equipment used for mountaineering and related activities this has resulted in the publication of a series of EuroNorms (EN standards) which have updated and replaced the previous national standards. As an example the previous BS (British Standard), DIN (German Standard) and AFNOR (French standard) for carabiners is now covered by EuroNorm EN12275.

This was facilitated by the formation of CEN (Committee for European Normalisation) and sub committees in each member state with a vested interest in that type of product or service.

CE marking of the product is achieved via submission of representative samples and technical documentation to an Accredited Notifed Body for test and approval to the relevant EuroNorm. On successful completion a CE Type Examination Certificate is awarded to the manufacturer by the notified body authorising the inclusion of the CE mark on the product.

On an ongoing basis the manufacturers Quality Assurance Management System is supervised by the notified body in order to ensure ongoing and satisfactory conformance of the Quality Systema and product to the requirements of the relevant reference standards.

WHAT IS A KILONEWTON ?
A Newton, or N, is a measure of force. It is equivalent to the force that would have to be exerted on a 1 kg mass to make it accelerate at a rate of 1 metre per second per second (1 m/s).

The definition of Force is:
FORCE = MASS x ACCELERATION.
So for the above we have 1 N = 1 kg x 1 m/s.

The acceleration due to gravity acting upon a body, with a mass of 1 kg, would result in a force of 9.81 N. (ie. 9.81 N = 1 kg x9.81 m/s where 9.81 m/s is the acceleration due to gravity).

Now 1 kN (kiloNewton) = 1000N so a rated strength of 25kN stamped on a product would be equivalent to 25000N or 2551 kg(acted upon by gravity).
(ie. 25 kN = 25000N = 2551 kg x 9.81 m/s ).

This is sometimes expressed in terms of kgf, or kilograms force, where 25kN = 2551 kgf