HAZTEC FR Workwear Brochure V2.5 - Flipbook - Page 8
ABOUT ARC FLASH TESTING
LAYERING GUIDE
ARC TESTING METHODS
UNDERSTANDING TEST METHODS & RESULTS
There are two test methods for ARC Flash
protective clothing:
There are Test Methods and Test Results for ARC Flash Clothing.
Here we provide a basic overview of the methods used for HAZTEC
Workwear and the resulting data.
IEC61482-1-2 COMMONLY KNOWN
AS THE ‘BOX TEST’
ABOUT LAYERING
The Box Test method gives a protective classification
of either APC 1 Class 1, 4KA (lower level of protection) or
APC 2 Class 2, 7KA (higher level of protection). This has
traditionally been the popular and most recognised standard
in Europe.
IEC61482-1-1: COMMONLY KNOWN
AS THE ‘OPEN ARC TEST’
BOX TEST METHOD
HAZTEC® BREGA FR AS ARC Hi-Vis Polo Shirt. ARC Flash
tested using the Box Test method.
The open ARC test method gives an ARC Thermal
Protective Value (ATPV) rating or an energy break open
threshold (EBT50) rating. This is becoming increasingly
popular as garment combinations certified to this method
can give figures that are more relevant in risk assessments or
ARC Flash calculations. For workwear within the HAZTEC®
product range, a single layer garment that is sold with an
ARC certification is commonly certified to class 1 on
the box test method.
ELIM has been introduced because the opinion of EU
was that 61842-1-1 could be in conflict with EU directive.
According to directive, no standard can impose harm to a
worker.
By this, ATPV/EBT imposes 50% probability that a worker
will sustain second degree burn in electric arc exposure.
This means that the worker will statistically have burns every
other time.
ELIM is the conservative calculation of risk of an electric
arc.ELIM the maximum incident energy that a protective
clothing can prevent against in a hazardous situation, with
0% probability of enough energy getting through the
garment to cause a second-degree burn.
HAZTEC® MERCURY FR AS ARC Hi-Vis Jacket ARC Flash
tested using the Open Arc test method and certified with both
a ATPV and ELIM value.
OPEN ARC METHOD
(JACKET, 9,6cal/cm2)
ATPV or EBT ratings - when garments are tested
using this method a rating per garment is achieved.
When worn in combination with other garments,
these ratings can be added together (as a guide to
some degree) but the total protective value of the
combination is only known when the garments are
tested as a combined set.
Mid Layer
(POLO SHIRT,4,6cal/cm2)
Base Layer
WEARING OF NON-ARC
CERTIFIED GARMENTS WITH
YOUR ARC GARMENTS
(BASELAYER, 6 cal/cm2)
Total
34.0cal/cm2
OUTER LAYERS
KEY TERMINOLOGY - IN SUMMARY
TEST METHOD
The type of ARC flash test applied to the garment. Either the
Box Test (often used in Europe) or the Open Arc Test (common
in the US but is our preferred test method on HAZTEC®
workwear.)
4kA/7kA
The test data results from a Box Test, now also known as APC 1
and APC 2.
ATPV RATING
The most common test result from an Open Arc Test, provided
as a calorific value.
ELIM RATING
The figure to watch out for moving forward and featured on
HAZTEC® garments. Often a lower calorific value but a safer
figure. This is the value at which there is a 0% probability of
second degree burns versus the ATPV value which is a 50%
probability of second degree burns.
8
Adding a class 1 garment with another class 1 garment
does not necessarily give you a class 2 rating and the
combined result can only be confirmed when the
garments are tested together.
Outer Layer
ABOUT ELIM (ENERGY LIMIT VALUE)
ELIM is the figure that will become the recognized value
that will be used. Larger electrical organizations where Arc
Flash Hazards are a daily risk will already be specifying this
figure. In the interim period it is important to be aware that
comparisons could be made between an ATPV and an ELIM
figure, of which ELIM will always be lower.
Class 1, 4KA and class 2, 7kA when garments are tested
using the box test method an ARC rating of either
class 1 or class 2 is achieved.
HAZTEC® Workwear, T: +44 (0)1280 841400,W: haztecworkwear.com
It is important to remember that the outermost layer
of your protective clothing must be FR and ARC rated.
To add a non-FR layer over your ARC rated garments
defeats the whole purpose of wearing ARC rated
garments – if that outer layer was to ignite, the heat
can transfer through your inner ARC garments to your
body.
GAPS BETWEEN YOUR GARMENTS
ALLOW AIR FLOW BETWEEN LAYERS
INNER LAYERS
Wearing non-ARC rated garments beneath your
ARC rated garments can also be the cause of serious
burn injuries. We recommend that if non-ARC rated
undergarments are worn that these are natural nonmelting fibres e.g. 100% cotton. Polyester type fibres
or similar fabrics that can melt should not be worn if
there is a flame, heat or ARC hazard present in your
workplace as this can cause serious burn injuries.
*figures shown are indicative
9
