Occasionally I don't talk about politics on this blog, and this is one of those days. I was going to write about Jeremy Corbyn, but that's a bit pointless, and besides my adoring public apparently wants to hear about women's hat etiquette. So this is what I know....
Women don't have to take their hat off as much as a man would do, unless it's a hat that a man would wear as well - such as baseball hat, or beanie. It seems the etiquette follows the style of hat rather than the gender of the person who is wearing it.
However, if a woman is wearing a more typically female style of hat, like those that you would wear to Ascot, for instance, then you have different rules.
Male "style" hats e.g. baseball hats, beanies
Remove these when indoors in most cases
Remove at religious ceremonies (unless head covering required)
Remove those when wanting to show respect i.e. when being introduced
Remove at work (unless hat is required)
Remove in the presence of ladies
Remove when in someone else's home
Remove at home (but you'd probably do that anyway, right?)
"Female style" hats
These are accorded different rules as they are considered to be part of a woman's "ensemble"
No need to remove in a restaurant
No need to remove at religious ceremonies
Remove when at work (unless hat is required)
Remove when it might block someone's view
Don't wear them on the dancefloor (more for practical reasons than anything else)
"Female style" Wedding hats
Many people don't wear them now.
Mother of the groom should have either the same brim size or smaller brim size than the mother of the bride
If you have worn a hat and so has the mother of the bride, you should wait till she takes hers off before you take yours off
A note on brims
Large is good (but not required) in the sun and during the day, as it's required for keeping the sun off, but can look like you are trying to attract attention (vulgar) later in the day - try and reduce brim size as you move towards the evening (tho not on the same hat - although perhaps there could be a Kickstarter in that idea!)
P.S. Never point out if someone has messed up with these rules. That's rude and thus vulgar and thus not to be done!