7 y/o with strange bumos

[Sandradee774]

This past week we've done a lot of swimming in a chlorinated pool. The other night I noticed on my seven-year-old son upper arm what felt like a rash. But when I look at it there's nothing there but I can run my finger over it I feel the tiniest when I can only explain like a little tiny bumps are scabs almost   It's not red or itchy. It's not swollen skin. But it feels almost like tiny scabs or pimples. He wears a swim shirt in the pool.
He has pretty good skin. Sensitive. He gets prickly heat once the summer starts but only in his stomach and chest and that's red. This rash is only on his upper arms.

[n8bean]

If it does not go away when he stops swimming, Id try putting some lotion on him after his next bath/shower.  My son has seasonal allergies and his skin gets just like that and goes away after a few lotion applications

[margypops]

possible allergy to the chlorine or other stuff they clean the pool with see if it goes away when you are not swimming .