Make your own free website on Tripod.com
The Student Nurse Forum     |     home  
Nursing Calculators   |   Conversions   |   Medical Terminology   |   Scientific Terminology   |   Self-Tests
Conversions
 This page was last updated on 15-Jun-02

Main Menu / Study Aids / Conversions
 Study Aids:
  Conversions
B
elow are some useful conversion factors to help you with your studies (especially helpful for the science classes!).


Units of Measurement | Metric & SI Prefixes | Conversion Factors

 
Units of Measurement

The metric system is used by scientists and health professionals worldwide.  A modified version of metric, called the International System of Units (SI) was adopted in 1960 to provide additional uniformity.  The table below notes common units of measurement in both metric and SI:

UNITS OF MEASUREMENT
Measurement
Metric
SI
Length
Meter (m)
Meter (m)
Volume
Liter (L)
Cubic Meter (m3)
Mass
Gram (g)
Kilogram (kg)
Time
Second (s)
Second (s)
Temperature
Celsius (0C)
Kelvin (K)

Length, time and temperature are fairly self-explanatory.  Volume and mass need a little more clarification.  Volume measures the amount of space occupied by a substance. Think of volume as a fluid measurement, such as how much water is in a glass.  Mass is a measure of the quantity of material an object contains.  It may be helpful to think of mass as a measurement of weight, such as the weight of a patient. It should be noted, however, that mass is not the same as weight.  Weight is the measure of gravitational pull on an object.  In space, a man will weigh less than on earth but the man's mass will not change.  That is why scientists measure mass instead of weight - mass does not vary.  

 
Metric and SI Prefixes

In both metric and SI, a prefix can be attached to any unit to increase or decrease its size by some factor of 10.  For example, a kilogram is equal to 1,000 grams; a milligram is equal to one-thousandth of a gram.  The table below illustrates this unique feature:

METRIC AND SI PREFIXES

Prefix

Symbol

Meaning

Numerical Value
Scientific
Notation
Prefixes that increase the size of a unit
mega
M
one million
1,000,000
106
kilo
k
one thousand
1,000
103
Prefixes that decrease the size of a unit
deci
d
one-tenth
0.1
10-1
centi
c
one-hundredth
0.01
10-2
milli
m
one-thousandth
0.001
10-3
micro
m
one-millionth
0.000001
10-6
nano
n
one-billionth
0.000000001
10-9

 
Conversion Factors

In the healthcare field, you will make changes in units everyday.  For example, you may need to convert someone's weight in pounds to their weight in kilograms to calculate a proper dosage for the patient's size.  Conversion factors are simple formulas that help you do this.  The first table below lists measurement equivalents.  The second table lists metric conversion factors and the third table lists metric-to-U.S. relationships and conversion factors.

MEASUREMENT EQUIVALENTS
Length
1 meter (m) = 100 centimeters (cm)
1 meter (m) = 1000 millimeters (mm)
1 meter (m) = 39.4 inches (in.)
1 inch (in.) = 2.54 centimeters (cm)
Volume
1 liter (L) = 1000 milliliters (mL) = 1000 cm3
1 liter (L) = 1.06 quarts (qt)
1 quart (qt) = 946 milliliters (mL)
Mass
1 kilogram (kg) = 1000 grams (g)
1 kilogram (kg) = 2.20 pounds (lb)
1 pound (lb) = 454 grams (g)
Temperature
0F = 1.8 0C + 32
0C = (0F-32)/1.8
K = 0C + 273
Gases
1 atm = 760 mm Hg
1 mole (STP) = 22.4 L
H2O
density = 1.00 g/l mL
melt = 80 cal/g
boil = 540 cal/g
SH = 1 cal/g C
Energy
1 Cal = 1 kcal = 1000 cal
1 calorie (cal) = 4.18 joules (J)

METRIC CONVERSION FACTORS
Metric Relationship (Equality)
Conversion Factors
Length
1 m = 1,000 mm
     1m           and        1000 mm  
1000 mm                        1m
1 cm = 10 mm
     1cm         and         10 mm  
  10 mm                         1cm
Volume
1 L = 1,000 mL
      1L           and        1000 mL  
1000 mL                         1L
1 dL = 100 mL
     1dL          and       1000 mL  
  100 mL                       1dL
Mass
1 kg = 1,000 g
     1kg          and        1000 g  
  1000 g                        1kg
1 g = 1,000 mg
     1g            and        1000 mg  
1000 mg                        1g

METRIC-U.S. RELATIONSHIPS & CONVERSION FACTORS
Relationship
Conversion Factors
Length
2.54 cm = 1 in.
    2.54 cm        and           1 in.    
       1 in.                          2.54 cm
1 m = 39.4 in.
     1m               and         39.4 in.  
  39.4 in.                             1m
Volume
946 mL = 1 qt.
     946 mL       and           _1 qt.  _
        1 qt.                           946 mL
1 L = 1.06 qt.
      1L               and          1.06 qt.   
  1.06 qt.                               1L
Mass
454 g = 1 lb.
    454 g           and          _1 lb.    
      1 lb.                             454 g
1 kg = 2.20 lb.
      1 kg           and          2.20 lb.   
    2.20 lb                            1 kg


Return to the top




Advertisements:


Click Here!