In article ,
Chris Bacon writes:
|
| Under moderately extreme conditions, people have had brain damage from
| wearing protective headgear.
|
| I'd like to see reference material.

Try a literature search (proper cites, not the Web) - it is a known problem.

| and this means that the absence of specific head-cooling causes
| trouble as soon as the average blood temperature approaches the brain's
| limit.
|
| That does not follow. You could have someone exercising very hard indeed
| in a cold environment, and I bet you they would not get heatstroke from
| wearing a hat.

So what? In case heatstroke has damaged your brain, let me remind
you of the context:

In article ,
Chris Bacon writes:
|
| So if you wear an impermeable lagged membrane over that part
| of your head your brain will "overheat"? I don't think so.

You may not think so, but it is nonetheless true.

The protective headgear to which I am referring as causing brain damage
was an approximation to "an impermeable lagged membrane".

| You've strung together a *lot* of wriggly words there. Stick to
| non-extreme gardening, and wear a hat.

The wriggling is all yours, I am afraid.

I never wear a hat, largely because I have a thick natural thatch.
However, many people want/need to, so my initial advice is good:

More importantly, it should be porous to water vapour, as
sweating is the primary mechanism for keeping the brain cool.

Don't wear a plastic bag - wear a cotton, linen, straw or even wool
hat instead.


Regards,
Nick Maclaren.