• givesomefucks@lemmy.world
    link
    fedilink
    English
    arrow-up
    4
    arrow-down
    3
    ·
    1 个月前

    Interesting

    Just imagine how much more interesting it would be if you asked questions instead of not understanding things and hoping people answered questions you hadn’t thought to ask…

    As I said, sweat has a lot to do with it, and as I didn’t think to imply because I I estimate people chronically: Humidity is just as important if not more so

    To test these recommendations in high-risk groups, Jay and colleagues recruited people over age 65, some of whom had heart conditions. As people age they perspire less, so they get less cooling from evaporating sweat. And cardiac problems such as heart attacks are one of the biggest dangers 
of overheating.

    The researchers tested 58 people inside special climate-controlled chambers that created two different climates: a humid one resembling places like Mumbai, India, at 38°C and 60% humidity, and a desertlike setting at 45°C and 15% humidity.

    When exposed to the moist heat for 
3 hours, even older people with coronary artery disease showed a 31% reduction in cardiac stress—based on heart rate and blood pressure—while sitting in front of a fan, compared with a separate test with no fan. When the participants were spritzed with water while in front of a fan they fared even better, with a 55% lower stress level. People without heart disease got even more benefit in all scenarios.

    “Under the hot humid heat conditions, we show definitely that fans are protective at a temperature above the threshold used by CDC,” Jay says. That, he says, is because by circulating the air, the fans enabled more moisture on the skin to evaporate than if air close to the body remained stagnant.

    By contrast, results in dry conditions starkly illustrated the dangers of misusing fans. The scientists stopped the experiments after testing just 14 people because their cardiac stress went through the roof as the fan blew hot air on them. Nearly half the participants couldn’t stay in the test room for 3 hours. The reason for that dramatic response: The air was so dry that any sweat quickly evaporated, resulting in little additional cooling as the fan bathed participants in extremely hot air, Jay says.

    https://www.science.org/content/article/when-is-it-too-hot-use-fan

    Anything else you say I’m sure will be similarly wrong, I’ll just never see it to explain how you’re wrong