Depending on his or her age, your child may use a hand-held device to measure how well he or she can breathe (peak flow meter).

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In a few minutes Lorelei brought out the peak flow meter, and when Davis blew into it he was back nearly to his normal reading of 380.

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With new chips and software, Eaton can meter and control the flow of electricity on plant floors to prevent sags and surges caused by lots of motors and digital devices starting up at once.

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Inside the riser pipe is a space about half a meter in diameter, large enough to hold the spinning drill pipe and bit and to allow the return flow of drilling fluid.

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