My house is also double grounded. Most aren't.

I always unplug my machine when I am done using it

We have the proctors but I always keep computers and my sewing machines unpluged when not in use.

I unplug even with surge protectors and a whole house protector. I wont take a chance especially since in Florida we had our condo hit and it fried our TV and TiVo.

I have 2 lightening rods outside and every time we get hit bl9ws out phone n modem. Now I run n unplug stuff and I have surge protectors lol

Same here. We get a lot of pop up thunder storms during the summer here in Maine and even though I have a rather pricey surge protector, I unplug when I'm not home.

Just another good reason to have a treadle on hand. I can sew and watch the storm (lightning storms and winds). Better thn most tv shows.

We learned years ago to unplug irons and machines when not using. I don't keep toasters, etc., plugged up either. I do leave my microwave plugged in, though.