Florida Drinking Water Operator "B" Practice Test

What is the primary cause of scale developing in water heaters, pipes, and fittings?

1. Soft water

2. Rainwater

3. Hard water

4. Filters

The correct answer is: Hard water

The primary cause of scale developing in water heaters, pipes, and fittings is hard water. Hard water contains a high concentration of minerals, particularly calcium and magnesium. When hard water is heated in a water heater or comes into contact with pipes and fittings, these minerals can precipitate out of the water as scale deposits. This process occurs because heating water reduces its capacity to hold dissolved minerals, leading to sediment formation that adheres to surfaces. Scale buildup can lead to several problems, such as reduced efficiency of water heaters, increased energy consumption, and clogged pipes. Managing this scale typically involves water treatment solutions, such as water softening, to replace calcium and magnesium ions with sodium ions, which do not contribute to scale formation. Therefore, hard water is the correct answer, as it directly causes the issue in question.