CSLB C-36 Plumbing ContractorPlanning and EstimatingHard
A plumbing contractor is reviewing a blueprint for a new medical laboratory specializing in chemical analysis. The lab design includes several sinks and equipment that will discharge highly corrosive chemical waste. To protect the building's drainage system and the municipal sewer, what specific type of drainage piping material should the contractor specify for these specialized waste lines?
- AType L copper pipe
- BGalvanized steel pipe
- CSchedule 40 PVC pipe
- DBorosilicate glass pipe
Show answer & explanationAnswer & explanation
Correct answer: D. Borosilicate glass pipe
Borosilicate glass pipe is highly resistant to a wide range of corrosive chemicals, making it the preferred material for laboratory drainage systems handling strong acids, bases, and solvents. While specialized, it offers superior chemical resistance compared to plastics or metals.
Why the other options are wrong
- A. Copper pipe will corrode rapidly when exposed to many strong chemical wastes.
- B. Galvanized steel pipe is highly susceptible to corrosion from acidic and many other chemical wastes.
- C. PVC has good chemical resistance to many common chemicals but can be attacked by strong solvents or specific acids/bases found in labs.
Chemical Waste Drainage Piping
Specialized piping used to convey corrosive or hazardous chemical waste from laboratories or industrial processes to treatment or disposal.
- Requires materials with high chemical resistance to acids, bases, and solvents.
- Common materials include borosilicate glass, polypropylene (PP), and PVDF (polyvinylidene fluoride).
- PVC and CPVC may be used for less aggressive chemicals but have limitations.
- Metal pipes (copper, steel) are generally unsuitable due to corrosion.
Memory trick: Glass is boss for corrosive loss.