Fire Resistant
cables - Publication of BS 5839-1:2002 - effective date July 2003
In summary, for a fire performance
cable to meet either of the two burn test classes of cable (this
also includes water and mechanical shock applied during the test of
one sample) called for by BS 5839-1:2002 and therefore to be suitable
for use on the installation of fire systems.
- 'Standard' cable -
BS 5839-1:2002 26.2d must meet the requirements of
-
- BS EN 50200:2000 PH30
- BS 8438-1:2003
- BS 7629-1:1994
- BS 6387-1:1997 Clause 11 CWZ
-
- 'Enhanced' cable -
BS 5839-1:2002 26.2e must meet the requirements of
-
- BS EN 50200:2000 PH120
- BS 8438-2:2003
- BS 7629-1:1994
- BS 6387-1:1997 Clause 11 CWZ
In addition both classes of fire cable must
meet the standards applicable for low smoke and zero halogen.
History of current standard
When
BS 5839-1:2002 was published in November 2002 the section on “Cables,
wiring and other interconnections” was heavily revised from the
previous 1988 edition. The previous edition BS 5839:1988 had used
BS 7629-1 and BS 6387 Cat. CWZ “Specification for performance
requirements for cables required to maintain circuit integrity under
fire conditions” as a series of tests to demonstrate the suitability
of fire resistant cables.
The
2002 edition states that “…it is now considered that the
temperatures, durations and methodology of the tests require
revision for cables of fire alarm systems complying with this part
of BS 5839” with reference to BS EN 50200: 2000 for the test
procedure, category PH 30 for "Standard Fire Performance
Cables" and PH120 for "Enhanced Fire Performance Cables".
When the new BS 5839:2002 standard was adopted in July 2002 the new
fire performance test, EN 50200 had still not been ratified to
include the test for Fire and simultaneous fire, water and
mechanical shock test but is now fully ratified and is used with
reference to the introduction of BS 8434: 2003.
In
August 2003, BS 8434:2003 was released as a guide for the “Method of
test for resistance to fire of unprotected small cables for use in
emergency circuits” but with modifications and additional
requirements, this standard is to be used in conjunction with
EN50200:2000 as it detail how to test with fire and fire, water and
mechanical shock and this standard is now fully ratified for use
with BS 5839-1 2002.
The
new amendments appear in BS 5839-1:2002 Clause 26.2 "d" and "e".
Clause "d" is for "Standard" Fire performance cables and clause "e"
is for "Enhanced" Fire Performance Cables.
BS 5839-1:2002,
Section 26.2, Clause d "Standard Grade Fire Performance
Cable.
In summary, cables complying with BS 5839-1:2002 "standard"
grade should at least comply with BS 7629, BS 6387 Category CWZ and
PH30 of EN 50200.
BS 6387 CWZ provides
tests to:
Category C.
Exposed to
Fire @ 950 Deg. C. for 3 Hours
Category W.
Exposed to
Fire @ 650 Deg C. for 15 Minutes, Then
Exposed to Fire @ 650 Deg C. with water for 15 Minutes
Category Z.
Exposed
to Fire @ 650 Deg C. for 15 Minutes, Then
Exposed to Fire @ 650 Deg C. with Mechanical Shock for 15
Minutes.
EN50200 PH 30 (with
reference to BS 8434)
Exposed to
flame / heat at 830 Degree's C. for 15 minutes, and then
Exposed to flame / heat at 830 Degree's C for 15 minutes
simultaneous exposure to water and shock.
EN50200 PH 120 (with
reference to BS 8434)
Exposed to
flame / heat at 930 Degree's C. for 60 minutes, and then
Exposed to flame / heat at 930 Degree's C for 60 minutes with
simultaneous exposure to water and shock.
BS 5839-1:2002,
Section 26.2, Clause E "Enhanced" Grade Fire Performance
Cable.
In summary, cables complying with BS 5839-1:2002 "standard" standard
grade should at least comply with BS 7629, BS 6738 Category CWZ and
PH120 of EN 50200 (Improved)
Update: 20/1/08
BS 8434:2003 is expected to be withdrawn when EN 50200 is fully
detailed and adopted. |