Empleado

Flame
Data

Test

Standards

Communications
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Cable

2007

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Table of Contents

Executive Summary

3

Introduction

3

The “Fire Cycle” and Material Chemistry

4

Fire Tests for Data Cable6

The NEC Fire Test Hierachy

9

European Union (EU) Fire Test Classes

11

North American and EU Fire Test Comparison

12

Data Cable Materials Selection

13

2

Executive Summary
Purchasers of data communication cabling products are primarily interested in the
data transmission characteristics of these cables. However, these products must
typically meet various flametest requirements in order to ensure the safety of
building occupants in the event of fire. Over the years, a number of fire safety
standards for data communications cable have evolved in North America and the
European Union. This paper will discuss and compare the most common flame test
protocols used in North America and the European Union. In addition, this White
Paper will describe the “FireCycle” and how these flame test protocols affect
material selection for data communication cables.

Introduction
The majority of data communication cables are designed to meet specific fire test
standards. The standards which will dominate data communications cable fire testing
in the near future are described within the American NEC (National Electrical Code)
and similar Canadian firetest standards, the European EN 50266, and the European
EN 50399 as part of the European Construction Products Directive (CPD). Also, many
of the data communications cable fire test protocols used outside of North America
and the European Union are derived from the fire test protocols in the codes and
standards described above.
The NEC is administered by the National Fire ProtectionAdministration (NFPA) and
although participation is voluntary, it is the de facto standard throughout most of the
US. Some large cities have codes which deviate from the NEC, most notably Chicago
and Las Vegas. The NEC contains articles which cover specific types of premise
wiring installed in buildings. Within these articles are references to the UL / NFPA
flame tests which these specific types mustmeet in order to comply with the code.
EN 50266 and IEC 60332-3 are virtually identical except for minor editorial
differences and are still the most commonly specified large ignition source (20kW or
greater) European Union flame tests for data communications cable. However, EN
50399 is part of the recently ratified CPD and should become a commonly specified
flame test protocol over the next fewyears.

3

The “Fire Cycle” and Material Chemistry
Before entering into a detailed discussion about flame testing of wire and cable
constructions, the “Fire Cycle” will be discussed.

Fire Cycle

Ignition

Heat

Oxygen

Fuel

There are four elements to the fire cycle, heat, fuel, oxygen, and ignition. Heat
causes the plastic in the cable to degrade. When the plastic degrades,it creates
combustible materials in both gas and liquid form. In the diagram above, we refer to
these combustible materials as “Fuel”. The fuel combines with oxygen, ignites and
releases heat. The heat released by combustion causes more plastic to degrade and
form combustible material, which combines with oxygen, which then ignites, which
then creates more heat. This cycle repeats endlesslyuntil one of the elements
necessary to continue the cycle are eliminated or reduced sufficiently to prevent the
cycle from continuing. Common ways to interrupt the fire cycle are:
Reducing the amount of fuel available to burn
Reducing the availability of oxygen to chemically react with the fuel
Reducing the amount of heat available to degrade the plastic
Some plastics, like polyvinyl...