Fluoridation Safety Seminar
 Jeff Zidek – Thatcher Company
Introduction
 The purpose of this presentation is to introduce
some important safety facts and other useful
information regarding fluoridation.
 Some properties of Fluoride
 Practical handling of Fluoride
 The main health hazards associated with Fluoride
Safety
 Safety is the name of the game.
 Play by the rules.
Safety Overview
 Respect and consider the hazards of the
chemical
 Consider your personal safety always
 Consider the others with whom you are
working and their safety
 Consider the purpose of the chemical that is
being use and know the name of the chemical
Fluorine
 Fluorine is a gas.
 Fluorine is the thirteenth most abundant element
found in the earth’s crust.
 Fluorine is always found as a combination of
chemicals.
 When the compound is dissolved in water the
compound dissociates into ions such as table salt.
 It is the fluoride ions that we are interested in for
public benefit.
Chemical Sources
 Fluoride can be found in a solid form in
minerals such as fluorspar, cyrolite and
apatite.
 Due to the dissolving power of water,
fluoride is found naturally in all waters.
 In general, the deeper the groundwater, the
greater the natural concentration of fluoride
in the water.
Drinking Water Fluoride
Compound Additives
 Sodium Fluoride
 Sodium Fluorosilicate
 Hexafluorosilicic Acid (Hexafluorosilicic
Acid) HFS or HFA
Sodium Fluoride
 Sodium Fluoride (NaF) is a white, odorless
material available as either a powder or in the
form of crystals.
 Powdered Sodium Fluoride is produced in
different densities:


Light grade – Less than 65 pounds per cubic foot
Heavy grade – About 90 pounds per cubic foot.
Sodium Fluorosilicate
 Sodium Fluorosilicate (Na2SiF6)
 Sodium Fluorosilicate is a white, odorless
crystalline powder.
 Sodium Fluorosilicate is 98% or greater in
purity.
 Sodium Fluorosilicate is sold in the same
densities as sodium fluoride.
Hexafluorosilicic Acid
 Hexafluorosilicic Acid (H2SiF6).
 Hexafluorosilicic Acid is a straw-colored,
transparent liquid.
 Hexafluorosilicic Acid is a 20 to 35 percent
solution with a pH of 1.2
 Hexafluorosilicic Acid must be handled with
care.
Safety
 Fluoride is an extremely safe compound at
the 1 ppm level found in water supplies.
 Operators may be exposed to higher levels
by handling the chemicals.
 The use of safety equipment is strongly
recommended when handling fluoride
compounds or performing maintenance.
Safety Gear for Fluoride
Powders
 Wear protective clothing





NIOSH/MSHA approved dust respirator
Goggles
Gauntlet neoprene gloves (12” minimum length)
Heavy duty neoprene apron
High top boots
Safety Gear for Fluoride
Powders Continued…
 Protective clothing should always be worn
whenever handling the fluoride powders.
 Protective clothing should be stored near the
entrance of the area where the fluoride
powders are stored.
 Avoid wearing the protective clothing into
other parts of the water plant.
Handling Bags of Fluoride
Powder
 Use a knife to open the bags and make a
clean cut.
 Gently pour the powder into the saturator to
raise as little dust as possible and empty the
bags completely.
 Do not store partially filled bags of powder
for later use.
Handling Bags of Fluoride
Powder Continued…
 Dispose of empty bags and wash your hands
immediately after handling the powder/bags.
 Never eat, drink or smoke in the area where
the fluoride is used or stored.
Dissociation of H2SiF6
 H2SiF6 = 2HF + SiF4(gas)
 And SiF4(gas) + 2H2O = 4HF + SiO2(solid)
 And SiF4(gas) + 3H2O = 4HF + H2SiO3(acid)
 And HF = H + F
Safety Gear for
Hexafluorosilicic Acid
 Always wear protective clothing.





Gauntlet neoprene gloves (12” minimum length)
Full 8” face shield and/or acid type safety
goggles.
Heavy duty acid type neoprene apron
Tall Chemical Resistant Boots
Safety showers should be located.
Safety Gear Continued…
 Only Neoprene, PVC and Natural Rubber
gloves are acceptable while handling fluorine
products.
 Latex and Nitrile gloves are not acceptable.
Handling Hexafluorosilicic
Acid
 Keep the acid off clothes and skin and don’t
breathe in the fumes.
 Use a transfer pump to move the acid from
one container to another.
Handling Hexafluorosilicic
Acid Continued…
 Dispose of empty acid containers as required
by state law.
 Wash your hands, equipment and protective
clothing after handling Hexafluorosilicic
acid. Do this immediately and before you do
anything else.
 Never eat, drink or smoke in areas where the
acid is stored or used.
Spill and Releases
 All spills must be handled with care.

1.
2.
3.
Steps to follow in the event of a spill or release.
Isolate the spill area and deny entry.
Stay upwind of the spill
Do not touch or allow anyone to touch the
spilled or leaked product.
Spill and Releases Continued…
4.
5.
6.
Use Personal Protective Equipment
Try to stop the source of the leak if it is safe to
do so.
Contain the spill so that it will not reach the
public ground or surface water. Prevent
discharge into sewers and waterways.
Spill and Release Containment
 Build a dike around the spill using lime
(Ca(OH)2)
 Do not use soda ash or caustic as this will
form sodium fluorosilicate and sodium
fluoride (both of these compounds are
regulated as hazardous substances)
 Lime will neutralize HFS liquid to form the
insoluble calcium fluoride.
Spill and Release Containment
Continued…
 Lime Neutralization



H2SiF6 + Ca(OH)2 forms CaSiF6 + 2H20
CaSiF6 + 2Ca(OH)2 forms 3CaF2 + Si02 + 2H2O
0.4 pounds of lime will neutralize 1 pound of
HFS liquid solution
Spill and Release Containment
Continued…
 DO NOT use metal buckets to recover any
HFS acid as it will react readily with metal.
Spill and Release Containment
Continued…
Spillage HFS Liquid
Lime Required
1 pound
0.12 pounds
55 gallons
65 pounds
1 – tote
Call HAZMAT
Bulk
Call HAZMAT
Any spills larger than 55 gallons should have a
HAZMAT response team
Fluoride Exposure
 There are two kinds of toxic exposure


Chronic toxic exposures (large doses of fluoride
spread over several years) and
Acute toxic exposures (a single massive dose)
Chronic Toxic Exposure
 Low level prolonged exposure (2 to 8 times
that of the optimal level) can mottle the
enamel of the teeth.
 At higher prolonged levels of exposure and
fluoride intake, osteosclerosis, calcification
of ligaments and tendons, and or vertebrate
consolidation can occur.
Acute Toxic Exposure
 Acute fluoride poisoning may result from
ingestion, inhalation or bodily contact with
concentrated fluoride compounds.
 Accidental ingestion is quite unlikely and not
a lot is known about acute fluoride poisoning
by ingestion because it is a very rare
occurrence.
Acute Toxic Exposure
Continued…
 Some Symptoms of acute poisoning

The body will tell us if there has been an
overexposure to fluoride:

Overdoses will include:
 Vomiting
 Stomach Cramps
 Muscular Weakness
 Difficulty in speaking
 Disturbed color vision and thirst
Toxic Exposure
 Concentrations of fluoride of 1.0 ppm has
been exhaustively studied and firmly
established as safe beyond question.
 To prevent overexposure, the best safety
measure is proper handling of fluoride
chemicals.
Fumes from HFS
 When fumes become irritating to the nose.


STOP IMMEDIATELY
Apply 3M Full face Respirator with 6006 Multi
Gas Vapor Cartridge
Fumes from HFS continued…
 HFS is a very unique chemical.


Irritation of the nose is the first sign that a
respirator must be donned.
A bloody nose follows the irritation if action is
not taken.
First Aid for Acute Toxic
Exposure
 First aid treatment should be started while
waiting for medical help.
First Aid for Air-Borne
Fluorides (Nose Bleed)
 Move the victim from the exposed area
 Keep the victim quiet;
 Place the victim in a sitting position, leaning
forward if possible;
 If leaning forward is not possible; place the
victim in a reclining position with the head
and shoulders raised
First Aid for Air-Borne
Fluorides (Nose Bleed) Cont...
 Apply pressure directly by pressing the bleeding
nostril toward the midline
 Apply a cold compress to the victim’s nose and
face.
 Insert a small, clean pad of gauze (not absorbent
cotton) into the nostrils and apply external pressure.
 Obtain medical assistance.
Skin Exposure from HFS
 Skin exposure from liquid HFS is more hazardous
than breathing the vapors.
 When liquid HFS comes in contact with the skin, it
feels much like water.
 Liquid HFS penetrates the skin quickly, burning the
skin and absorbing into tissue.
 The pain will become intense, deep if not washed
off immediately.
First Aid for Acid Splash
 Wash away the chemical with large amounts
of water as quickly as possible.
 Remove the victims clothing from the
affected area and continue washing for at
least 5 minutes.
 Where skin damage has occurred, cover the
burns with a dressing bandage.
First Aid for Acid Splash
Continued…
 If the eye is involved, immediately begin to wash
the eye, eyelid and face.
 Hold the eyelid open and wash the eye for at least
15 minutes.
 After a thorough washing, cover the eye with a
clean, dry protective dressing and hold bandage in
place.
 Even seemingly minor eye injuries can become
serious.
 Seek immediate medical assistance for the victim.
Questions?