Siniat Intumescent Acoustic Sealant is not suitable for use with cPVC pipework and must not be used for this application. Incorrect product selection in these situations can lead to compatibility issues and may compromise the performance and durability of both the pipework and the fire‑stopping system.

Please see guidance for fire stopping pipe penetrations 
 

Requirements when working with cPVC pipework

Where cPVC pipework is present, it is essential that the selected fire‑stopping solution:

• Is specifically tested and confirmed as compatible with cPVC materials
• Is installed in accordance with the fire‑stopping manufacturer’s technical literature and installation guidance
• Meets the requirements of the project fire strategy, including the required fire resistance period

Due to the chemical sensitivity of cPVC, some sealant formulations can lead to environmental stress cracking (ESC) or long‑term material degradation.

Compatibility should therefore be verified against both:

• The fire‑stopping manufacturer’s guidance
• Where applicable, independent material compatibility guidance, such as Lubrizol assessments for cPVC systems, to ensure that the long‑term integrity of the pipework is not adversely affected
   

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