Related Legal Terms & Definitions. 1  COMPETENT WITNESS One who is legally qualified to be heard to testify in a cause. 2  RESPECTABLE WITNESS One who is competent to testify in a court of justice. 3  CREDIBLE WITNESS A credible witness is one who is competent to give evidence, and is worthy ofâ¦.
In general, combustibility of polymers depends on their chemical structures. Polymers with more carbon atoms in their macromolecular structure (e.g., PE, PP, PS, PMMA) are more combustible than polymers containing halogen atoms (e.g., PVC, PVDC, PTFE).
PVC Disposal and Recycling. Household and infrastructure pipes are often made from PVC. Polyvinyl Chloride, or PVC, is the plastic commonly known as vinyl, which can be found in everyday items from bottles to house siding. PVC content is identified on plastic containers by the number 3 in the triangular recycle symbol.