Galaxy is a leading low smoke zero halogen (LSZH) cable supplier offering custom and stock LSZH cable and LSZH wire. LSZH cables are often used where safety, along with performance and reliability, are critical. They are typically specified for use in highly populated, enclosed public spaces where flame resistance, low smoke production and reduced toxic/corrosive gas emissions during combustion are critical.
LSZH cable/wire refers to cables where the cable jacketing and insulation is made with materials that produce low/limited smoke and non-toxic halogens when exposed to fire or high temperatures. There is also low smoke cable and zero halogen cable / halogen free cable.
Low smoke zero halogen cables are used when fire safety is critical, especially in enclosed spaces. A number of fires in transportation facilities and other locations led to the development of LSZH cables. In these emergency fire situations, the low smoke factor helps maintain visibility and can reduce respiratory damage, while zero halogen material cuts the production of toxic, halogenated gases.
Halogen free cable/wire, also called zero halogen cable, refers to cables where the cable jacketing and insulation is made with materials that produce no toxic halogens when exposed to fire or high temperatures. These halogen free cables are used when smoke considerations are minimal. Halogen-free cables also do not use materials that may have an environmental impact.
Low smoke cable/wire, also called limited smoke cable, refers to cables where the cable jacketing and insulation is made with materials that produce no or only small amounts of smoke when exposed to fire or high temperatures. These low smoke cables are used when halogen considerations are minimal.
Because of their low smoke and toxicity benefits, LSZH cables are often chosen for a multitude of applications. These include:
LSZH insulation and jacketing can be used to manufacture nearly any type of cable, including but not limited to:
In some locations, there are regulations that require the use of low smoke zero halogen wire/cable. Local codes should be checked to see if LSZH wires are required.
Galaxy has successfully transitioned a large number of cable projects from unapproved cable specifications to cables that now meet stringent low smoke zero halogen requirements. This expertise and experience is a strong reason to choose Galaxy for LSZH cable.
Also, there are various combinations of cable compounds with different characteristics. There are some low-smoke compounds that are not halogen free, and some halogen free compounds that are not considered low smoke. Galaxy&#;s Sales Engineers can provide guidance in selecting a cable solution that is well suited for specific applications and understand the challenges that come along with the cable selection process. No matter the environment or desired functionality of the cable, a LSZH cable can be manufactured that allows equipment to function as intended when fire and smoke safety is critical.
Galaxy offers LSZH, halogen free, and low smoke insulation and jacket material for cable with:
LSZH cable and wire from Galaxy is available with the following materials:
Galaxy offers LSZH cable in the following ranges of technical specifications:
LSHF cables are made up of halogen free compounds that are good fire retardants but emit less than 0.5% hydrogen chloride gas and smoke when burnt. In case of fire these cables produce small amounts of light grey smoke and HCL gas which greatly increases the chances of escape from populated areas. There&#;s no PVC in these cables, hence no harmful fumes or dense black smoke are given off in case of fire.
LSF cables are flexible and low cost alternative to PVC cables but can still produce a dangerous amount of toxic gas and smoke. Whereas LSHF cables are less flexible and a higher cost but with a significant reduction in toxic gas and smoke. So in a high risk populated area where escape is limited LSHF cables are strongly recommended. But in low risk areas where the evacuation is easy and high flexibility is required, PVC could still be a good choice.
Though all of the above perform very differently with regards to
the amount of toxic fumes and smoke they produce however they all could, and in
many cases do, pass the CPR test to class Eca.
So where does CPR come in I hear you ask!
SUNUA supply professional and honest service.
Most cables designed for permanent installation within domestic, residential and commercial buildings are now subject to the Construction Products Regulation (CPR), covered by BS EN which became a legal requirement in July . The standard is primarily about the spread of fire and heat release, not the toxicity of gases or smoke given off.
The regulation classifies products into one of seven classes, but in most instances, only five classes will apply to cables. Lower classes Fca and Eca undertake a basic vertical flame test to BS EN -1-2. If there is a high level of flammability, it would be classified to Class Fca (testing to Fca can be conducted &#;in-house&#;). However, for the cable to meet the requirements of Class Eca, the test has to be conducted by an authorised test house, known as a Notified Body (NB) or Approval Body (AB).
In the test, a single cable of approx. 60 cm is mounted vertically using two clamps, a flame is applied to the bottom end for 60 seconds (or 120 seconds in the case of cable diameters greater than 25 mm). The test is deemed passed if, after the flame has been removed, the burning cable extinguishes itself and the fire damage is less than 425mm. It is irrelevant how long the cable burns before extinguishing itself.
Great! I hear you say! &#;All I have to do is ensure that the cable I install is at least CPR class Eca compliant and I don&#;t have to worry about what material it&#;s made from!&#;
The 18th edition of BS recognises that where applicable, cables need to meet CPR requirements and carry a Euroclass for fire performance. BS does not specify or recommend which Euroclass to use in an environment or application, and notably, nor does it outlaw using cables that emit toxic fumes and smoke in the event of fire. Specifiers and installers must therefore ensure the cables they select are appropriate for the fire risks in the building or application and any contractual terms.
Part B of The Building Regulations does offer additional guidance.
&#;The primary danger associated with fire in its early stages is not flame but the smoke and noxious gases produced by the fire. They cause most of the casualties and may also obscure the way to escape routes and exits. Measures designed to provide safe means of escape must therefore provide appropriate arrangements to limit the rapid spread of smoke and fumes.&#;
&#;Okay, so I simply specify the highest CPR class I can find, just to be safe!&#;
Unfortunately specifying to what many might consider to be a &#;safe&#; level might prove cost prohibitive for the contractor, who may also discover cables to higher classifications scarce or impossible to come by. Test procedures to gain even Cca compliance are costly for manufacturers and can involve lengthy R&D to meet the standard &#; there are many cable types where it&#;s simply not cost effective to test to that level.
Another complicating factor is that cables redesigned to pass higher CPR classes may shift in electrical or data performance and physical properties - factors that may effective how they perform or their method of installation.
Lower CPR classes focus on spread of fire, not toxic fume and
smoke emissions. Specifiers considering the emissions of cables when burnt need
to choose Low Smoke Halogen Free (LSHF) but beware, as we&#;ve already learned, there
are plenty of ways terminology and acronyms can trip you up.
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