Question
What are some common Hardness unit conversions?
Summary
Converting Hardness
Answer
The table below shows the factors to convert hardness from one unit of measure to another. For example, to convert mg/L CaCO3 to German parts/100,000 CaO, multiply the value in mg/L x 0.056.
To convert from mg/L to grains per gallon, multiply by 17.1.
Note: meq/L = N × 1000
To convert from mg/L to grains per gallon, multiply by 17.1.
Note: meq/L = N × 1000
| Units of measure | mg/L CaCO3 |
British gr/gal (Imperial) CaCO3 |
American gr/gal (US) CaCO3 |
French parts/ 100,000 CaCO3 |
German parts/ 100,000 CaO |
meq/L | g/L CaO | lb/ft3 CaCO3 |
|---|---|---|---|---|---|---|---|---|
| mg/L CaCO3 | 1.0 | 0.07 | 0.058 | 0.1 | 0.056 | 0.02 | 5.6x10–4 | 6.23x10–5 |
| English gr/gal CaCO3 |
14.3 | 1.0 | 0.83 | 1.43 | 0.83 | 0.286 | 8.0x10–3 | 8.9x10–4 |
| US gr/gal CaCO3 | 17.1 | 1.2 | 1.0 | 1.72 | 0.96 | 0.343 | 9.66x10–3 | 1.07x10–3 |
| French p/100,000 CaCO3 |
10.0 | 0.7 | 0.58 | 1.0 | 0.56 | 0.2 | 5.6x10–3 | 6.23x10–4 |
| German 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 |
| lb/ft3 CaCO3 | 16,100.0 | 1123.0 | 935.0 | 1610.0 | 900.0 | 321.0 | 9.0 | 1.0 |