The measurement of body heat is a means of assessing whether the body's temperature is within a narrow, safe range.

Glass thermometer: First clean the thermometer with cool, soapy water or rubbing alcohol. Gripping the end opposite the bulb, shake the thermometer down until it reads 95 degrees Fahrenheit or less. You can measure the temperature on three body locations:

• Oral: Place the thermometer under the tongue and close the mouth using the lips to hold the thermometer tightly. The patient must breathe through the nose. Leave the thermometer in the mouth for 3 minutes.

• Rectal: For this method, use a rectal thermometer. This method is recommended for infants and small children who are not able to hold a thermometer safely in their mouths. Lubricate the bulb of the thermometer with a petroleum jelly. Place the small child face down on a flat surface or lap. Spread the buttocks and insert the bulb end of the thermometer about 1/2 to 1 inch into the anal canal. Remove the thermometer after 3 minutes.

• Axillary (in the armpit): Place the thermometer in the armpit, with the arm pressed against the body for 5 minutes before reading. This is the least accurate method for using a glass thermometer.

Read the thermometer by gripping the end opposite the bulb so that the numbers are facing you. Roll the thermometer back and forth between your fingers until you see a silver or red reflection in the column. Compare the end of the column with the degree marking in the lines on the thermometer.

Electronic thermometer: You use this thermometer like a glass thermometer, but you read the temperature on a digital visual display.

Plastic strip thermometer: These plastic strips contain a heat-sensitive liquid crystal that changes color to indicate the temperature. This method is not very accurate.

Place the strip on the forehead and read it after 1 minute. Read it while the strip is in place.

Oral plastic strip thermometers are also used. The mechanism is similar to that of strip thermometers that are placed on the skin

Normal temperature by age (in degrees Fahrenheit):

• Children 0-3 months: 99.4
• Children 3-6 months: 99.5
• Children 6 months to 1 year: 99.7
• Children 1 year to 3 years: 99.0
• Children 3 years to 5 years: 98.6
• Children 5 years to 9 years: 98.3
• Children 9 years to 13 years: 98.0
• Children 13 year to adult: 97.8 - 99.1

• Farenheit to Centigrade:
  • Start with Fahrenheit temperature and subtract 32
  • Multiply result by 5
  • Divide by 9
  • The result equals degrees Centigrade
• Centigrade to Farenheit:
  • Start with Centigrade temperature
  • Multiply by 1.8
  • Add 32
  • The result equals degrees Fahrenheit