Free NEHA Water Quality Questions and Answers — Questions and Answers
Question 1: Which of the following is the most common method used to disinfect drinking water?
- Chlorination (Correct answer)
- Boiling
- Filtration
- Fluoridation
Correct answer: Chlorination
Chlorination is the most widely used method to disinfect drinking water, killing bacteria, viruses, and other pathogens.
Question 2: What is the maximum contaminant level (MCL) for lead in drinking water according to the U.S. Environmental Protection Agency (EPA)?
- 0.015 mg/L (Correct answer)
- 0.05 mg/L
- 0.1 mg/L
- 0.5 mg/L
Correct answer: 0.015 mg/L
The EPA's MCL for lead in drinking water is 0.015 mg/L (15 parts per billion) to protect against the harmful effects of lead exposure.
Question 3: What does pH measure in water quality?
- The amount of dissolved oxygen
- The concentration of heavy metals
- The acidity or alkalinity of water (Correct answer)
- The temperature of water
Correct answer: The acidity or alkalinity of water
pH is a measure of how acidic or basic (alkaline) water is, with values ranging from 0 (most acidic) to 14 (most basic).
Question 4: Which of the following contaminants is often responsible for causing algal blooms in water bodies?
- Nitrates and phosphates (Correct answer)
- Heavy metals
- Pesticides
- Chlorine
Correct answer: Nitrates and phosphates
High levels of nitrates and phosphates in water can cause excessive algae growth, leading to harmful algal blooms and water quality issues.
Question 5: What is the main health concern associated with high levels of nitrates in drinking water?
- Increased risk of cancer
- Bone deformities
- Blue baby syndrome (methemoglobinemia) (Correct answer)
- Neurological disorders
Correct answer: Blue baby syndrome (methemoglobinemia)
High nitrate levels in drinking water can reduce the oxygen-carrying capacity of blood in infants, leading to blue baby syndrome.
Free NEHA Water Quality Questions and Answers
Which of the following is the most common method used to disinfect drinking water?