In modern building and public facility construction, cable safety and environmental
performance have become core considerations. Low-Smoke Zero-Halogen (LSZH cables) ,
with their unique material formulation and safety characteristics, are gradually replacing
traditional PVC cables and becoming the standard for high-security locations such as
hospitals, subways, and data centers. This article systematically analyzes their technical
advantages from four IV. Mechanical and Cost Balanceperspectives:material composition,
combustion characteristics, mechanical properties, and high-frequency application
scenarios.
1. Materials and Structure: Dual Guarantees of Environmental Protection
and Safety
Halogen-Free Formula
LSZH cables(Low-Smoke Halogen-Free Cables) utilize materials such as polyethylene (PE),
cross-linked polyethylene(XLPE), or polyolefins, completely eliminating halogen-containing
flame retardants (such as the chlorine in PVC). This approach prevents the release of toxic
gases such as hydrogen chloride during combustion. The PVC sheath of conventional
cables decomposes at high temperatures, releasing corrosive gases that can accelerate
equipment damage and threaten the respiratory system.
Zero Heavy Metal Addition
By replacing lead and cadmium-containing stabilizers with inorganic flame retardants such
as aluminum hydroxide or magnesium hydroxide, this product meets flame retardancy
requirements (oxygen index ≥ 32) while complying with RoHS environmental directives.
It is suitable for use in heavy metal-sensitive medical and food industry environments.
2. Combustion Characteristics Comparison: Lifeline in Fire
Characteristics of LSZH cables(Low-Smoke Halogen-Free Cables) and Ordinary
PVC Cable
About LSZH cables(Low-Smoke Halogen-Free Cables)
Smoke Density: Light transmittance > 60% (IEC 61034 standard)
Toxic Gases: Generates only CO₂ and H₂O, non-toxic
Flame Spread: Self-extinguishing, flame retardant rating meets IEC 60332-1
About Ordinary PVC Cable
Smoke Density: Light transmittance < 20%, thick smoke obstructs escape vision
Toxic Gases: Releases carcinogens such as HCl and dioxins
Flame Spread: Highly combustible, fire spreads rapidly
3.High-Frequency Application Scenarios: Safety-Indispensable Areas
Rail Transit
Subway tunnels are confined spaces, and the low-smoke properties of LSZH cables(Low-
Smoke Halogen-Free Cables) ensure at least 90 minutes of escape time in the event of
a fire (EN 45545-2 standard).
Data Centers
Server clusters operating at high frequencies require cables that remain stable even at high
temperatures.
LSZH materials offer a temperature resistance (-40°C to 120°C) far exceeding that of PVC (
up to 70°C),while also preventing halogen corrosion of delicate circuits.
Medical Facilities
Areas like MRI rooms require zero halogen interference, and the chlorine content of
conventional cables can affect imaging accuracy.
4. Mechanical and Cost Balance
Although LSZH cables are 20%-30% more expensive than conventional cables, their tensile
strength(≥12.5N/mm²) and chemical resistance significantly extend their service life.
Conclusion: Technological Upgrades Drive Industry Standards
With mandatory requirements for flame-retardant cables in standards such as China's
GB/T 19666-2019, LSZH technology is evolving from a "high-end option" to a "basic
configuration." In the future, its safety and environmental advantages will further unlock
its value in emerging high-frequency, high-load scenarios such as 5G base stations
and new energy charging stations.
