Here, in winter, we seal up the house (and other buildings) and crank up the heat. This dramatically reduces the relative humidity. Right now I have the following humidity levels: Basement 24% Parlor (where the humidifier is) 29% My daughter's house 29% If I slide off an untreated sofa and touch a doorknob there is a visible spark. I have grounded anti-static mats on my work surfaces. Where in the world are you? Tropics? Allen -----Original Message----- From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf Of Justin Richards Sent: Sunday, March 10, 2019 7:51 PM To: Microcontroller discussion list - Public. Subject: Re: [OT]: Any ideas on reducing static build up when vacuuming On Sun, 10 Mar 2019 at 23:54, graham foulkes wrote: > I am also very sensitive to static build up and disruptive discharge and > when living in upstate NY, winter was a particularly trying time. The air, > on those cold dry days, when the water vapour froze out, was a near perfect > insulator, coupled with static generating materials, nylon carpets, > > I think the documentation I have had to read and comply with surronding ESD must have originated somewhere with similiar conditions to yours. I was always at odds with "ESD is more of a hazard in winter". Static shocks are less of a problem in our winter. I am guessing because it often rains and never below freezing and therefore humidity is higher. We also get very humid periods in summer but less so. Justin --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .