Explanation of what is happening for Fabric/Garment Testing

As we know heat from an electric arc is an important hazard that workers need to be protected from. Once end users have carried out their own risk assessment and if they have identified as a result of this to provide their workforce with FR protective clothing, there are new standards and test methods that they can refer to

Clothing is subject to draft norm IEC 61482-2. In order to choose adequate protective clothing, the potential incident heat energy (in units of energy per square surface) caused by an electric arc and to which a worker may be exposed, needs to be calculated in this thorough risk assessment.

Within the garment standard, the norm refers to fabrics that can be tested to "open arc", covered by by IEC 61482-1-1 (now EN 61482-1-1) or "arc in a box" covered by IEC 61482-1-2 / EN 61482-1-2

Quantifying the arc rating of a protective garment
1. The arc rating is most commonly quantified by the ARC THERMAL PERFORMANCE VALUE (ATPV) determined by the open arc test method EN 61482-1-1. The ATPV represents the maximum incident thermal energy in units of energy per surface area (e.g. kJ/m2 or cal/cm2) that a fabric can support before the wearer will suffer 2nd degree burns.

The break-open threshold energy (or EBT) is another fabric characteristic. It represents the highest incident energy exposure value on a fabric where the garments do not exhibit break-open. The formation of holes in the fabric caused by break-open would allow heat or flames to pass through. Workers are assumed safe if the arc rating of their clothing (or ATPV value) exceeds the electric arc incident energy as calculated in the worst case scenario of a risk assessment.

NOTE: IEC and EN 61482-1-1 are equivalent to the American Standard Test Method ASTM F 1959M)

2. The box test is another way to measure the protective performance of clothing against the thermal effects of an electric arc and is defined in the IEC 61482-1-2 / EN 61482-1-2 test method. In this test, the fabric is exposed to an electric arc confined in a specific box with a specific electrode arrangement.
Class 1
Arc Duration= 0.5s Arc Current = 4kA
Class 2
Arc Duration= 0.5s Arc Current = 7kA

A fabric passes the test:
- if the heat transferred behind the fabric does not cause second degree burn (i.e. is below the Stoll curve)
- if the after flame time is below 5 seconds
- if there is no melting to the inner side of the fabric
- if a hole caused by the arc is not larger than 5 mm in every direction (in the inner most layer).

Test conditions for Class 1 try to simulate typical exposure conditions for a short circuit current of 4 kA protected by devises limited the duration of the arc to 0.5 seconds in confined space, and of 7 kA respectively for Class 2.

(To be used in Low Voltage Systems only)

DuPont TM Arc-Man(r)
This equipment developed by DuPont measures the ATPV value of protective fabrics and garments in simulated open electric arc incidents. This is configurated to IEC/EN 61482-1-1.

Incident energy is calculated on several parameters influencing an electric arc, such as current, duration of the arc, electrode material, the gap between the electrodes and the distance of the tested fabrics or garments to the arc.

Arc-Man(r) can test fabrics on panels, measuring the ATPV value of the fabric system (in cal/cm2) so that it can be compared with the incident energy calculated in the end user's risk assessment. Arc-Man(r) can also perform complementary garment tests on a torso to show the effect of a garment's design and integrity of manufacture, allowing an assessment of the garment's behaviour (e.g. of the closure system, the pockets, etc.).

ARC-MAN(r) IS SIMILAR TO KINECTRICS TEST FACILITY

Recommendations

- DuPont recommends that all layers are made of inherently flame resistant materials
- inappropriate underwear could ignite or melt, thus having an adverse effect on protection aggravating the outcome of an electric arc incident
- Nomex(r) offers single layer and multi-layer protective clothing solutions against electric arc hazards, conforming to IEC 61482-2 when tested according to IEC 61482-1 / EN 61482-1-1 (Open arc incidents) and IEC 61482-1-2 / EN 61482-1-2 (Arc in a Box or confined arc incidents).

Electric arc protective clothing can receive IEC 61482-2 certification if one of the following requirements are met:
- the ATPV value of the clothing must be at least 4 cal/cm2
- the clothing has to pass at least the electric arc box Class 1.

DuPont recommends to the user to ask weavers and garment manufacturers for an offering of fabrics, fabric systems and garments, which meet his or her specific arc rating needs and also his needs of other important properties in the best combination. Our NQP weavers, knitters and garment manufacturers can provide you with tested and certified solutions.

A great website giving much more detail and a contact of where you will be able to purchase garments is

www.arcflashprotection.co.uk

Some Contacts at NQP Weavers

Estambril
Jordi Querol
Tel: +34 93 748 4545
Fax: +34 93 7274430

E-Mail: <j.querol@taginnovacion.com
www.estambril.com

Frische
Göschel Hans
E-Mail: goeschel@tfritsche.de
Mobile: +49 9252 99050


Fuchshuber (Knitter)
Jörg Vois
Tel.: +49 (0)7129/6915-20
Fax: +49 (0)7129/6915-15
Email: j.vois@fttex.com


Ibena
Britta Smeulders - Technical Manager
Tel: +49/(0)2871/287-131
FAX: +49/(0)2871/287-130
Mobil: +49/(0)174/3426021
E-Mail: britta.smeulders@ibena.de

Sofileta
Colin Clark
Tel: +44 7827 966599
Email: cclark_sofileta@btinternet.com

Garment Manufacturers Providing Arc Clothing

JK Ross
Chris Ross
+44 7802 558995
www.arcflashprotection.co.uk
Email: cross@jkross.co.uk

Iturri
Eddie Impey
Email: eimpey@iturri.com

Wenaas
Jim Hanna
Mobile: +44 7866 559860
Email: Jim.Hanna@wenaas.co.uk

ROFA BEKLEIDUNGSWERK SCHUTTORF
Attn: Mrs. Silke Kamps
Fabrikstrasse 23
Postfach 1280
48457 Schüttorf
Germany

Tel: 0049 59 23 898 0
Fax: 0049 59 23 898 80

silke.kamps@rofa.de

www.rofa.de

[/U]ALWIT GmbH[/U]
Attn: Mr. Siegfried Assmann
Kattegatweg 6
46446 Emmerich-Elten
Germany

Tel: 0049 28 28 91 46 23
Fax: 0049 28 28 91 46 46

s.assmann@alwit.com
www.alwit.com

FPG ENERGOCONTRAKT
Attn: Mr. Alexander Bolshunov
Business Center “Arabat Fashion House”
Karmanitsky per.9
119002 Moscow
Russia
Tel: 007 095 9371615
Fax: 007 095 9371614
duge-net@energocontract.ru

PWG BEDRIJFSVEILIGE KLEDING B.V.
Attn: Mr. T. Sorgedrager
Postbus 103
4460 AC Goes
The Netherlands
Tel: 0031 113 21 34 40
Fax: 0031 113 23 26 75
t.sorgedrager@pwg.nl

www.pwg.nl


I'd be delighted to respond to your queries