The measurement of body temperature may be helpful for
monitoring whether a person is ill, or whether treatment is
working. A high temperature is a fever. How the test is
performed The American Academy of Pediatrics (AAP) recommends
against using glass thermometers with mercury. The glass can
break, and mercury is a poison. Electronic thermometers are the
most recommended type. The temperature is seen on an easy-to-
read display. A probe can be placed in the mouth, rectum, or
armpit. Mouth -- place the probe under the tongue and close the
mouth. Breathe through the nose, and use the lips to hold the
thermometer tightly in place. Leave the thermometer in the mouth
for 3 minutes or until the device beeps. Rectum -- this method
is for infants and small children who are not able to hold a
thermometer safely in their mouth. Place petroleum jelly on the
bulb of a rectal thermometer. Place the small child face down on
a flat surface or lap. Spread the buttocks and insert the bulb
end about 1/2 to 1 inch into the anal