Cut Resistant Hand Protection
It is important to
ensure that the right hand protection is of primary concern in every workplace.
Lacerations are the #1 safety issue in most plants with common causes ranging
from hand protection not being worn, poor compliance to PPE (personal
protection equipment) programs and PPE simply
misapplied. The COSTS of not doing so could be extremely heavy and are often
not fully realized until after the fact. The Iceberg Principle for costs of
injuries includes direct costs such as medical costs, workmen’s compensation
and worker’s loss time. Indirect costs include hours lost to first aid, hours lost
to assisting and transporting victims, hours lost to handling inquiries, cost
of damaged equipment, administrative costs and lost hours used for
investigation. These costs far outweigh the price of proper hand protection on
all hands.
On numerous occasions
safety professionals in the supply chain walk into work situations where cost and
safety are primary concerns. While most if not all companies put safety first,
there is definitely a cost sensitivity that is hard to ignore. Advanced textile
materials have come a long way in providing solutions that offer optimum
protection at continuously more affordable prices. It therefore helps to have
an understanding of these materials, the way they are tested and what those
tests mean.
Currently in North America there are two ASTM
tests in practice to determine cut resistance of textile materials, one being
the ASTM F1790-97 testing protocol and the other is the F1790-05 protocol. Both
tests consist of a measurement of the amount of pressure applied to a razor
blade while moving over the material in question without cutting through for
0.8 inches (05 Method) or 1,0 inches (97 Method). In principle, the higher the
force/load (usually measured in grams) the material withstands, the better the
cut resistance.
Another process often referenced is the European standard EN388, which can be
either a "Couptest" method for cut resistance or a TDM machine based
test (a TDM machine test protocol is similar to ASTM). In general the Couptest
consists of a circular blade moving back and forth across the material under a
fixed force/load of 5 Newtons/500g while the blade rotates in the opposite
direction to the back and forth movement. The test measures the number of
repetitive cuts needed to cut through the material. The result is then compared
to the cut resistance of a reference cotton material and provides a cut index.
As an example, an index of 5 means that the material is 5 times more cut
resistant. The index is as follows:
Level 0:
<1.2x
Level 1: 1.2x – 2.4x
Level 2: 2.5x – 4.9x
Level 3: 5.0x – 9.9x
Level 4: 10.0x – 19.9x
Level 5: >20x
The EN388 test is also accompanied by abrasion, tear and puncture tests.
One thing that must be noted is because of the way these various tests are
performed and measured, there is no cross-reference between the European and
North American tests. It is not possible or proper to equate any result in the
ASTM testing to any result in the EN388 testing.
The International Safety Equipment Association (ISEA) developed the
"ANSI" table as a reference guide for test results from ASTM test
protocols, these guidelines for cut resistance are:
Level 0: <
199g
Level 1: 200g – 499g
Level 2: 500g – 999g
Level 3: 1000g – 1499g
Level 4: 1500g – 3499g
Level 5: >3500g
It is extremely
important to understand the testing methods and testing levels quoted above and
imperative to compare ‘apples to apples’. In North America
safety specialists should ensure that firstly, the quoted levels are ANSI and
not EN388 levels as they are not directly comparable. Further, even within the
ANSI guidelines the spread is quite large for level 4 between 1500 and 3499
allowing for a vast and significant range of cut resistant products to achieve
a cut level 4. Therefore it is always helpful to have not just the level that a
particular product achieves but also the specific cut load (in grams) achieved
in that range.
While numbers and
levels quoted above are extremely helpful in narrowing the range of product to
use in a particular application it should not be the only qualifier. The
testing and the subsequent level ratings simply provide a guideline which states
that one material performed X and another material performed Y. One can gauge
that if X>Y then the first material is more cut resistant – but only in the
context of the test. Examining the tests, both are performed using a sharp
razor blade under a controlled environment. In practice, most applications
requiring cut resistance are not set in such a controlled environment. Some
applications have parts that are oily, have a serrated edge or even have sparks
and flames involved. For these reasons, it is understandable to set a minimum
level or cut test result as criteria for choosing hand protection, but not the
only criteria. Careful examination of the application and any extraneous
hazards which may be present, is an absolute necessity to select the correct or
ideal hand protection.
Fo Abiad,
President
Windsor
Textiles Limited
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