Technical Information

Technical Information

EN Standards


NFPA 1983



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 (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

Fall factor

3 Sigma

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:

M.B.S   – (3 )

Where: M.B.S is the MINIMUM BREAKING STRENGTH as stamped on the product or RATED STRENGTH information in this catalogue.  is the mathematical symbol for LESS THAN or EQUIVALENT TO  is the MEAN VALUE obtained from the sample or range of samples tested.  is the SAMPLE STANDARD DEVIATION of the test results obtained (this is the statistical MEASURE OF VARIABILITY from the sample or range of samples tested.)