What AquamarineSteph said. They will definitely pace things, and do whatever is necessary to keep things going. Our Guides actually bought us some little hand-held battery powered fans after we all totally melted in Hong Kong. They came in very handy!! I wish we'd had them *in* Hong Kong!
That said, there's only so much they can do -- be sure and let them know if you need to stop or whatever. They certainly don't want anyone getting ill!
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