B Exam: Iron, Manganese and Fluoride
What is the Primary MCL for Fluoride?
4
What is the Secondary MCL?
2
What is the purpose of adding fluoride to water?
To prevent caries, Cavities
Adding to much fluoride to water will cause?
Mottling your teeth (Staining them brown)
What do you give someone who has swallowed fluoride?
Water or Milk
What is the first symptom of swallowing fluoride?
Vomiting
What is the first symptom of inhaling fluoride?
Nose Bleed
If you use sodium fluoride in fluoridation, what must be done to the water if the hardness is above 75?"
Soften the water
When feeding sodium fluoride with a saturator, above what water hardness will scaling occur?
10
How many ppm of fluoride must be added to the finished water if the raw water fluoride content is 0.15 ppm and the desired fluoride limit is.8 ppm?
0.65 ppm
In Question 10, how many pounds of 100% F will be added per day if the WTP treats 10 MGD?
54 LBS (0.65 x 10 x 8.34)
What is a day tank?
A tank that holds enough chemical to feed water produced in a day.
What type of pump is used to feed chemicals?
Positive Displacement (Piston)
Recommended Control Limits are fluoride concentrations are based on?
Recommended Control Limits are fluoride concentrations are based on?
What is the most common fluoride compound used in water treatment?
Hydrofluosilicic Acid
The three most common fluoride compounds used in water treatment are?
Hydrofluosilicic Acid (H₂SiF₆); Sodium Fluoride (Na); Sodium Silcofluoride (Na₂SiF₆)
When choosing fluoride-pumping equipment, the most important criteria is?
Accuracy
Fluoride doses must never be metered against a?
Negative or Suction Head
Fluoride systems must be designed with the means to prevent?
Backsiphonage and Overfeeding
Fluoride systems should be designed by?
An engineer
If an operator gets fluoride on his skin or in his eyes, the recommended first aid is?
Flush with large amount of water for 15 minutes Eyes - Flush and see a doctor)
Never operate a positive displacement pump against?

A form of backflow caused by a negative or below atmospheric pressure within a water system is called?
Backsiphonage