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    Created in 2008, Phoenix Rising is the largest and oldest forum dedicated to furthering the understanding of, and finding treatments for, complex chronic illnesses such as chronic fatigue syndrome (ME/CFS), fibromyalgia, long COVID, postural orthostatic tachycardia syndrome (POTS), mast cell activation syndrome (MCAS), and allied diseases.

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  1. maddietod

    CO2 meter

    I bought an Aranet4 CO2 meter to test air freshness on an upcoming train trip. The meter is used as a proxy for COVID contamination; an air exchange rate giving readings under 800 is best. The literature says that over 1000 CO2 ppm, people start having cognitive problems. I tested the 2...