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Electrical short circuits are a common cause of major fires, leading to serious damage to people and property. Therefore, types of cables with fire-resistant, slow-burning and low-smoke properties such as LSZH cable have been developed to minimize these risks. The article below helps you understand in detail the properties, applications and how to choose the right LSZH cable for your projects.
1. Introduction to LSZH Cable
1.1 What is LSZH Cable?
LSZH cable (short for Low Smoke Zero Halogen) is a type of electrical cable with insulation and sheath made from special rubber compounds that contain no halogens (chlorine, fluorine, bromine, etc.) or smoke-producing agents. As a result, when exposed to fire, this type of cable produces minimal smoke and no toxic gases like HCl or HF, preventing suffocating smoke.
Additionally, LSZH cable also possesses other excellent properties such as slow burning and self-extinguishing, thereby minimizing the risk of fire spreading and property damage. Due to these advantages, LSZH cable is becoming the preferred choice for modern residential and industrial electrical installations.
Besides the name LSZH, some alternative abbreviated terms or variants are used by some manufacturers, but the common purpose is to indicate the low smoke and halogen-free properties. Here are some names you may encounter:
- LSOH (Low Smoke Zero Halogen) is often used interchangeably with LSZH, with only a small difference in naming but the same technical properties, widely used in certain regions.
- LS0H is a simplified abbreviated form, replacing “Zero” with the number “0”, but still retaining the technical meaning of low smoke halogen-free cable.
- LSFH (Low Smoke Free Halogen) is used by some manufacturers to emphasize the absence of fluorine, suitable for strict environmental requirements.
- OHLS is a less common inverted form that may appear in some specific documents, but LSZH and LSOH remain the widely used names in the industry.
1.2 LSZH cable classification
Based on fire resistance, LSZH cables are divided into three levels: A, B and C.
- LSZH cable grade A: This is the type of cable with the highest fire resistance among the three grades. Grade A LSZH cable is often used in projects with strict fire safety requirements such as high-rise buildings, large-scale shopping malls, hospitals and other crowded public areas.
- LSZH cable grade B: Grade B LSZH cable has lower fire resistance compared to grade A, but still meets the safety requirements for medium and small-scale projects. This type of cable is suitable for installation in small shopping centers, hotels, apartment complexes and office buildings.
- LSZH cable grade C: Grade C LSZH cable has the lowest fire resistance among the three grades, suitable for projects with basic fire safety requirements. This type of cable is commonly used in homes, home offices and low-density areas.
The choice of appropriate LSZH cable grade depends on the fire safety requirements of each project. International standards and local regulations also play an important role in determining the type of LSZH cable to be used. Regardless of grade, LSZH cables are a safe and effective solution to minimize the risks and consequences of fires.
1.3 Technical standards
To be classified as LSZH cable according to international regulations, products must meet strict standards from organizations such as IEC or BS, specifically:
- Standards on low smoke and halogen-free properties: IEC 60502-1; IEC 60754-1&2; IEC 61034-2; IEC 60684-2; BS 7211; BS 7846; BS 6724; BS 7629; BS EN 50267-2-1; BS EN 50268-2.
- Standards on flame retardancy and slow burning: IEC 60331; BS 6387; IEC 60332-1; IEC 60332-3 hoặc BS EN 60332-1; BS EN 50266-2.
These standards are strictly applied in the production of electrical cables in many developed countries around the world, ensuring the highest quality and safety.
2. Comparing LSZH and PVC
Understanding the criteria of each type of cable will help you choose the right product for each specific application:
Clearly, with superior advantages in fire safety, LSZH cable is the optimal choice for most modern electrical installations. Although the cost is slightly higher than PVC, this is considered a reasonable investment to minimize the risk of fire damage to people and property.
3. Practical applications of LSZH
With its superior advantages, LSZH cable is increasingly being applied in many fields:
3.1. Applications in construction
LSZH cable is used in high-rise buildings, apartments, hospitals, shopping centers to ensure safety for people and property. This type of cable has high flame retardancy, limiting the risk of smoke suffocation when an incident occurs.
3.2. Applications in industry
In industrial park infrastructure such as factories, workshops… where there are many production lines and sensitive electronic equipment, LSZH cable is prioritized to ensure safety, minimize the risk of fire spreading, causing damage to machinery and property.
3.3. Applications in public transport
Public transport systems such as subways, buses, airports, tunnels, and stations are also one of the important applications of LSZH cable. Because this area is crowded with people, the use of flame-retardant cables is always prioritized to ensure the safety and lives of passengers.
4. Guide to choosing LSZH cable
To select the appropriate type of LSZH cable, you need to consider the following factors:
- Rated voltage and current: The operating voltage and rated current must be suitable for the equipment used.
- Environment and installation conditions: The cable must be compatible with the surrounding environment such as temperature and humidity. It is necessary to consider whether the cable can withstand mechanical impacts and harsh weather conditions.
- Standards and certifications: Only use LSZH cables that fully meet the standards and certifications of reputable organizations at home and abroad such as IEC, BS…
- Cost, quality and lifespan: Choose a reputable supplier to select cables with reasonable quality and cost, do not choose products of unknown origin that pose many risks during use.
- Consider each specific application to choose the appropriate cable for each project. For example, for high-rise buildings, use fire-resistant LSZH cables with low heat and flame spread to ensure the safety of residents.
If you do not have experience in selecting LSZH cables, you can consult experts or reputable cable suppliers, they will give more specific advice based on the requirements and conditions of each project to choose the most suitable cable.
5. Frequently asked questions (FAQs) about LSZH
1. Is LSZH cable more expensive than PVC cable?
Considering the same technical specifications, LSZH cable is typically 15-20% more expensive than PVC cable. However, this is an acceptable price difference given the safety advantages that LSZH cable provides. The reduced cost of fire prevention when using LSZH cable will help offset this price difference.
2. Can LSZH cable be used outdoors?
Yes, there are now UV-resistant LSZH cable lines suitable for outdoor installation. This type of cable is coated with a special sheath that helps resist the effects of UV rays and harsh weather conditions such as rain, intense sunlight or the humid and salty environment in coastal areas. When installing, it should also be noted that the lifespan of the cable under weather effects may not be the same as indoor installation.
3. Comparing LSZH cable with ordinary fire-resistant cable?
Basically, both types have the ability to prevent flame spread, but LSZH cable has many more outstanding advantages:
- Produces less thick smoke, avoiding affecting visibility and causing suffocation in case of an incident.
- Does not contain toxic halogen components such as HCl, HF.
- Good self-extinguishing ability.
- Smoke is less corrosive to property and equipment.
Therefore, LSZH cable is considered a breakthrough development and safer than ordinary fire-resistant cable.
6. Conclusion
LSZH cable is increasingly becoming a popular trend because it meets the growing fire safety needs in civil works, transportation, factories and workshops… In addition to its superior flame retardancy, it also helps minimize toxic gases and produces less smoke, reducing the risk of damage to people and property in the event of an incident.
For those who are learning about the properties and important applications of LSZH cable, especially electricians, electrical engineering students new to the profession or those interested in fire safety, the article has provided you with a comprehensive overview of LSZH cable. This will help you make the right choices about LSZH cable for your projects and works.
