Hach DR/850, Procedures Manual, Page: 15 / 460

15
CHEMICAL ANALYSIS INFORMATION
, continued
Hardness Conversion
Table 2 lists the factors for converting one unit of measure for hardness to
another unit of measure. For example, to convert mg/L CaCO
3
to German
parts/100,000 CaO, multiply the value in mg/L x 0.056.
Table 2 Hardness Conversion Factors
Units of
Measure
mg/L
CaCO
3
British gr/
gal
(Imperial)
CaCO
3
America
n gr/gal
(US)
CaCO
3
French
parts/
100,000
CaCO
3
German
Parts/
100,000
CaO
meq/L
1
g/L CaO
lbs./cu ft
CaCO
3
mg/L
CaCO
3
1.0 0.07 0.058 0.1 0.056 0.02 5.6x10
-4
6.23x10
-5
English
gr/gal
CaCO
3
14.3 1.0 0.83 1.43 0.83 0.286 8.0x10
-3
8.9x10
-4
US gr/gal
CaCO
3
17.1 1.2 1.0 1.72 0.96 0.343 9.66x10
-3
1.07x10
-3
Fr. p/
100,000
CaCO
3
10.0 0.7 0.58 1.0 0.56 0.2 5.6x10
-3
6.23x10
-4
Ger. p/
100,000
CaO
17.9 1.25 1.04 1.79 1.0 0.358 1x10
-2
1.12x10
-3
meq/L 50.0 3.5 2.9 5.0 2.8 1.0 2.8x10
-2
3.11x10
-2
g/L CaO 1790.0 125.0 104.2 179.0 100.0 35.8 1.0 0.112
lbs./cu ft
CaCO
3
16,100.0 1,123.0 935.0 1,610.0 900.0 321.0 9.0 1.0
1
‘epm/L, or ‘mval/L’
Note: 1 meq/L = 1N/1000