Compare the actual grades
Material names are a starting point. Chemical resistance, temperature limits, fire behaviour and fabrication requirements depend on the particular product and conditions. Ask the responsible designer to identify the proposed grade and supporting compatibility information.
Our chemical-resistant PVC ducting guide explains the information needed for a FumeCare enquiry.
Create a common application brief
| Factor | Information to compare |
|---|---|
| Chemistry | Substances, concentrations, mixtures and cleaning agents. |
| Temperature | Normal operation and foreseeable excursions. |
| Environment | Indoor or outdoor position and site exposure. |
| Construction | Joints, supports, fabrication and access. |
| Project requirements | Relevant fire, pressure and other design criteria. |
Include the connected components
A duct material decision also affects fittings, transitions and connections to the cupboard and fan. Review the assembly rather than only a straight length of material. Keep all interfaces on the drawing and specification.
The fitting schedule helps document those interfaces. Our chemical exhaust fan guide provides the corresponding questions for the air-moving equipment.
Make the decision traceable
- Keep the chemical and operating brief with the specification.
- Record the exact selected material and product.
- Retain the compatibility assessment and relevant limits.
- Identify who approves any material substitution.
- Review the decision when the process changes.
A substitute should be assessed against the same conditions, including the jointing and support arrangement. This keeps a later repair consistent with the original design decision.