I noticed an incident some time ago reported at
where it appeared a designer took a similar suggestion as earlier on this thread and attempted to use weaker pvc pipes in what appeared to be a common a plant application. There are other similar cases of which I am aware. The happenings indicate sometimes services are more demanding, and pipes more vulnerable, than perceived, and real safety factors afforded by a substantial and robust piping system (vs pressure and perhaps in less obvious fashion localized support stress/spans/deflection, and vibration/resonance etc.) are apparently quite helpful. It should be remembered also that plant personnel are often walking and working immediately around these exposed lines (if for nothing else than to exercise valves etc.), and many plants are also the scene of a lot of continual (and often quite close) outside visitation and also construction activity, where pumps and other heavy units are being added, removed, maintained etc. and pipe being adjacently routed etc., and fracture toughness safety/risk vs, collateral damages etc. can be a very real issue.
In the latter regard, I am also aware of an incident in per account at
a worker was demolishing pipes in the basement of a college dormitory when a piece of iron pipe soil pipe fell on a pressurized pvc water line. That pvc pipe burst, thereafter knocking the worker knocked off the ladder and causing him to sustain “serious physical injuries”. A nasty lawsuit and long legal wrangling ensued.
While it is admittedly not the same sort of “plant”, I will also note the contemporary, real cost of accidents working around pipes can now be quite substantial, which is revealed in the similar sounding accident etc. report at
. Per this account a maintenance worker fell from a ladder onto a 6” pvc drain pipe attached to a acid tank, “The force of the maintenance worker's fall broke a six-inch PVC pipe nipple that was attached to a green chemical hose resulting in him being sprayed with sulfuric acid. A co-worker who had been holding the ladder for the maintenance worker came to the rescue and was also sprayed by sulfuric acid. The maintenance worker ultimately died from complications arising from his burn wounds.”, “The injured workers also sued the tank manufacturer claiming that the provision of a six-inch long PVC discharge pipe rendered the tank defective and unsafe in that it should have been stainless steel, which is much more durable and stronger than PVC piping. The maintenance worker suffered third degree burns over 50% of his body. He was placed in a drug-induced coma and died from complications relating to his burn wounds 37 days later.”, and as a result of lawsuits, “The total settlement to the family of the burned worker who died from his wounds was $6,603,000.00 while the injured worker who returned back to work received $4,047,000.00. The combined settlement of $10,650,000.00 was one of the largest settlements ever in the Commonwealth of Pennsylvania.” It appears sometimes a few feet of cheap pipe aren't really cheap!
Again, I am aware of a great many other unfortunate accidents etc. from working around/with weak pipes. While the actual cost and time/distraction to all parties and their management personnel who happen to be somehow around/involved, as well as who is responsible and/or pays for same, can be endlessly debated, I don’t believe anyone really wants to be in such “Whauhauppened?” situations.