The use of PVC in data and electrical cabling installations is widespread in Kenya. Most electrical and data cables are sheathed in the compound and almost all conduits in use are made from PVC as well.
Polyvinyl chloride (PVC) is the second most widely used plastic in the world. More than half of the world’s production goes into construction materials. It is relatively cheap to produce (ignoring cost to health and the environment) and can be made into either rigid or flexible products.
It is an established fact that, in case of a fire, PVC-coated wires can form hydrogen chloride (HCl) fumes; the chlorine serving to scavenge free radicals that are present in the atmosphere and, thereby, providing the source of the material’s fire-retardant properties. However, hydrogen chloride fumes can also pose a serious health hazard in their own right, because the fumes are toxic. And hence most fatalities in building fire accidents are caused by this toxic fumes and not the fire itself. PVC contains high concentrations of chlorine (56%), along with various chemicals to make it suit specific applications. PVC cable insulation and sheathing, for example, contains ‘plasticizers’’ that make it flexible. These chemicals, many of which are toxic, can leach out or be emitted into the atmosphere when burnt.
We seek to move away from cabling and conduits that contain PVC insulation and/or sheathing and go towards alternative compounds. The drive for this is obviously environmental issues, health and safety concerns. We should be adopting Low smoke zero halogen(LSZH) cables and non-halogenated conduits especially in electrical and data installations where smoke can be a major hazard(example, large tunnels and communal areas like halls and airports). Consultants and building developers should start specifying PVC-free materials before it is too late.
Policy makers, environmentalists and consultants need to advocate for large scale phase-out of PVC because of the many toxic chemicals it contains. For example, dioxin, an environmental pollutant is produced as a by-product of vinyl chloride manufacture and from the incineration of waste PVC. Dioxins cause cancer in humans and are among the most powerful carcinogens known. They also cause a whole range of other health effects on the reproductive, endocrine, and immune systems. Highly exposed populations, such as those that eat a lot of fish, meat, or dairy products, are at higher risk. Vinyl chloride is known to cause cancer in humans. It also can cause nerve damage, immune reactions, and other serious health effects in high enough doses. Lead which is still used as an additive in some PVC products, particularly wire insulation is a highly toxic metal that devastating impacts on children’s nervous systems. Phosgene gas is also another toxic gas produced when PVC is burned at temperatures below complete combustion. Phosgene, an odourless gas that can damage the lungs, is one of the substances used in chemical warfare!
When building, remodeling, or rewiring a building, the type of cabling is specified by building codes which in turn are specified by fire codes. Most widely used wires in Kenya have PVC insulation and sheathing. We ought to change our electrical codes as a country and advocate for use of halogen-free products. Cable and conduits manufactures in Kenya ought to embrace this and help initiate the revolution of PVC free products.
Low smoke zero halogen (LSZH) -rated cables ought to be adopted as a code. LSZH denotes cable jacketing that is non-halogenated. It is composed of thermoplastic compounds that emit limited smoke and no halogen when LSZH-rated cables are exposed to flames or high-heat sources. In the event of a fire, chlorinated materials release poisonous HCl that can form hydrochloric acid, whereas LSZH cables do not produce any dangerous gases/toxic smoke when it is exposed to flame. Conduits manufactured from PVC also ought to be phased out and instead adopt those manufactured from non-halogenated compounds.
