Unit 24

Volume or Liquid Measurement

Basic Principles of Volume or Liquid Measurement

• In the English system, the units for volume or liquid measurement are drops, teaspoons, tablespoons, ounces, pints, and quarts.

• In the metric system, the base unit for volume or liquid measurement is the liter.

Converting Volume or Liquid Measurements

• Conversion from one unit to another follows the same rules as linear or mass measurement.

• To convert between metric volume measurements and English volume measurements, follow the same rules used for linear or mass and weight measurements to convert between English and metric units.– The easiest way to convert between English and

metric measurements is to set up a proportion.

Volume or Liquid Measurements

• Example: A patient on an intake and output (I & O) record drinks 2 1/2 cups (cp) of coffee. The geriatric assistant must record this amount in milliliters (mL). – How many mL does he record on the I & O

record?– Find an English-metric equivalent: 1 cp = 240

mL

Volume or Liquid Measurements

– Set up a proportion:

– Multiply the extremes: 1 x X = X– Multiply the means: 240 x 2.5 = 600

– The patient drank 600mL of coffee.

Practical Problem

• Prepared infant formula comes in 1-liter (L) cans.

• If an infant drinks 150 mL per feeding, how many feedings are in 1 can of formula?

Practical Problem

• Make all units the same (1L = 1,000mL). Then set up the proportion and cross-multiply:

• Each can of formula provides 6.7 feedings.