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Joined 2 years ago
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Cake day: September 18th, 2023

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  • Expose those Roman road designs to today’s vehicle loads, frequency, and speed and they won’t last long either.

    As for getting utility sizing right forever so that they never have to be dug up again, that’s highly impractical as communities change - they grow, shrink, densify. Industries can move in and out of an area changing demand. Regulations change. Water mains and sewers age and fail and are replaced on a schedule. When new service connections are added, workers have to get to the main. And if they’re in a tunnel large enough for workers and equipment to remove and replace utilities, we’re talking a subway tunnel under every road and large access points every thousand or so feet. Tunnels will also deteriorate, flood, etc.











  • Chlorinated water adversely affects PEX pipes. I don’t know that the amount of microplastics or nanoplastics has been quantified in a study yet.

    https://pubs.acs.org/doi/10.1021/acs.est.9b03673

    The mechanical properties and lifetime of PEX were reduced after exposure to chlorinated water. (6) Prompted by concerns about the effect of chlorine dioxide on the chemical integrity of pipe materials, the pressure, tensile strength, and oxidation induction time were evaluated at constant temperature to assess the damage to pipe samples after exposure to chlorine dioxide for one year. (7) Overall, pipe aging due to long-term disinfectant exposure could cause decreased antioxidant contents; increased crystallinity; chain rupture; hydroxyl, carbonyl, and/or vinyl group production; and visible cracks in pipe walls.

    Can such an aging process lead to MP and/or NP leaching into the drinking water network? On the basis of aging mechanisms and material performance characteristics, we propose that MPs and/or NPs can be leached from aging pipes.

    The Brita pitcher comment is about my own growing paranoia about plastics that get scratched or cracked. I don’t know the conditions and time line under which this particular formulation of plastic keeps it from shedding MPs.



  • stillwater@lemmy.mltoMemes@lemmy.mlWhy still using the imperial system?
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    2 years ago

    There are (huge) costs to retooling production to move from imperial to metric. Even if a company wanted to make that move they’d have to transition in phases and will likely end up with additional equipment to maintain. There’s also significant training for workers (who will likely commit errors in the beginning) which will impact production. And what happens to the old equipment? I’d guess a significant portion of that would end up getting scrapped and landfilled.