Plenum Formulations Go

New PVC Plenum Formulations Let Telecom Cable Manufacturers Meet Ul Flame Resistance Requirements with an Antimony-Free Solution.


The metallic element antimony is a highly effective flame retardant in many polymers, such as polyvinyl chloride (PVC). Over the past 40 years, antimony has been included in PVC plenum formulations to help suppress flame propagation and to meet UL 910 and NFPA  262 requirements.

Antimony is commonly used in wire and cable applications because it is considered the most effective flame retardant additive available, and has synergy with other components that are used in these formulations. However, antimony is listed on California’s Proposition 65 list of chemicals published and updated annually, which may subject OEMs to certain requirements under the Proposition 65 legislation.

GEON® was tasked by several telecom cable manufacturers to develop a PVC formulation that meets the following Critical to Quality (CTQ) outputs:

  • No antimony in the formulation
  • Passes UL 444 and UL910 requirements for category communication cables
  • Processes at adequate line speed
  • Meets or exceeds all current performance requirements of customers for current plenum grades


GEON created a solution that would provide excellent flame resistance and low smoke generation while reducing the amount of heavy metals in today’s plenum formulations. This resulted in the development of Plenstar™ WJJP622, a PVC plenum formulation without antimony for use as a jacketing material in category communication cables. This newly developed material is suitable for shielded and unshielded designs over 4 FEP twisted pairs.


With excellent flame- and smoke-resistant characteristics, Plenstar WJJP622 flame retardant material enables manufacturers to pass UL910 flame and smoke specifications with an antimony-free solution. In addition, the formulations allow them to keep up with a growing demand for plenum products, and the desire to proactively move toward more sustainable material designs as highlighted in Proposition 65, that meet or exceed all cable requirements specified in UL 444 for category cables.

WJJP622 grade adds another exceptional PVC plenum option to the existing Plenstar lineup for jacketing applications in CAT 3, 5e, 6 and 6a cables.

Using Plenstar material:

  • Significantly reduced amount of heavy metals
  • Decoupled pricing from heavy metals market
  • Allowed Proposition 65 compliance while meeting performance requirements