Toxicology and Poisoning

Hydrogen Fluoride

Hydrogen Fluoride (HF) and Hydrofluoric Acid CAS: 7664-39-3; UN 1052 (anhydrous)/UN 1790 (solution)

Synonyms include hydrogen fluoride, fluoric acid, hydrofluoride, hydrofluoric acid, and fluorine monohydride.

• Victims exposed to HF vapors only do not pose a significant risk of secondary contamination; however, victims whose clothing or skin is contaminated with HF liquid or solution can secondarily contaminate response personnel by direct contact or through off-gassing vapors.
• Hydrofluoric acid is a serious systemic poison. Its severe and sometimes delayed health effects are due to deep tissue penetration by the fluoride ion. The surface area of the burn is not predictive of effects.
• Most hydrogen fluoride exposures occur by inhalation of the gas and dermal contact with hydrofluoric acid.

Hydrogen fluoride is a colorless, fuming liquid or gas with a strong, irritating odor. It is usually shipped in cylinders as a compressed gas. HF readily dissolves in water to form colorless hydrofluoric acid solutions; dilute solutions are indistinguishable from water. It is present in a variety of over-the-counter products at a concentration of 6% to 12%.

Although hydrofluoric acid is weak when compared to most other mineral acids, it can produce serious health effects when exposure occurs by any route. These effects are due to the fluoride ion's aggressive, destructive penetration of tissues.

Routes of Exposure --

Inhalation -

Inhalation hazards result not only from exposure to HF gas but also from fumes arising from concentrated HF liquid. Even fairly low airborne concentrations of HF produce rapid onset of eye, nose, and throat irritation.

Skin/Eye Contact -

Most hydrogen fluoride exposures occur by cutaneous contact with hydrofluoric acid. The fluoride ion, which penetrates tissues deeply, can cause both local cellular destruction and systemic toxicity.

Ingestion -

Ingestion of even a small amount of hydrofluoric acid is likely to produce systemic effects and may be fatal.

Properties --

Description: Colorless gas or fuming liquid; weak solutions have the appearance of water.

Warning properties: Disagreeable, pungent odor at <1 ppm; irritation of eyes and throat at 3 ppm

OSHA PEL (permissible exposure limit) = 3 ppm (averaged over an 8-hour workshift)

OSHA STEL (short term exposure limit) = 6 ppm ( 15-minute sample)

NIOSH IDLH (immediately dangerous to life or health) = 30 ppm ERPG-2 (emergency response planning guideline) = 20 ppm

Molecular weight = 20.01 daltons

Boiling point (760 mm Hg) = 67.1 degree F (20 degrees C)

Vapor pressure (34 degrees F) = 400 mm Hg

Vapor density = 0.7 (air = 1)

Miscible with water with release of heat

Nonflammable

Sources/Uses -

HF is primarily an industrial raw material. It is obtained commercially by action of sulfuric acid on the mineral fluorspar. HF is used in separating uranium isotopes, as a cracking catalyst in oil refineries, and for etching glass and enamel, removing rust, and cleaning brass and crystal. It also is used in manufacturing silicon semiconductor chips. Some consumer products that may contain HF include automotive cleaning products (for aluminum, chrome), rust inhibitors, rust removers(for ceramic tubs, sinks, fabrics), and water spot removers.

Health Effects

• HF differs from most other mineral acids. In addition to its corrosive effect as an acid, the fluoride ion readily penetrates the skin, causing destruction of deep tissues. Absorption of significant amounts of HF by any route may be fatal.
• Often, patients exposed to HF (<20%) initially are asymptomatic; effects can be delayed 12 to 24 hours.
• Systemic effects can include hypocalcemia, hypomagnesemia, and hyperkalemia.

Mechanism of injury. The toxic effects of HF are due primarily to the fluoride ion, which is able to penetrate tissues and bind intracellular calcium and magnesium. This results in cell destruction, local bone demineralization, and systemic hypocalcemia, hypomagnesemia, and hyperkaleremia. The effects of HF may continue for several days.

Respiratory -

Inhaled HF mist or vapor affects initially the nasopharynx and eyes. Mild clinical effects include mucous membrane irritation and inflammation, coughing, and bronchospasm. Severe clinical effects include almost immediate laryngospasm and laryngeal edema, resulting in upper airway obstruction. Pulmonary injury may evolve rapidly or may be delayed in onset for 12 to 36 hours. Noncardiogenic pulmonary edema, bronchoconstriction, and atelectasis can occur. Pulmonary effects can result even from splashes on the skin.

Dermal -

Depending on the concentration and duration of exposure, skin contact may produce pain, erythema, and deep, slow-healing burns.

Acid concentrations over 50% (including anhydrous HF) cause immediate severe, throbbing pain and a whitish discoloration of the skin, which usually proceeds to blister formation.

HF solutions from 20% to 50% may produce pain and swelling, delayed by up to 8 hours.

HF solutions of less than 20% cause almost no immediate pain on contact but may cause delayed serious injury 12 to 24 hours after contact.

Ocular -

Mild effects of HF vapor exposure include rapid onset of eye irritation. More severe effects, which may result from even minor hydrofluoric acid splashes, include sloughing of corneal surface epithelium, conjunctival edema, corneal stroma edema, and ischemic necrosis. Potentially permanent corneal opacification may develop immediately or after several days.

Gastrointestinal -

Ingestion of hydrofluoric acid may cause corrosive injury to the mouth, throat, and esophagus. Hemorrhagic gastritis occurs commonly. Nausea, vomiting, diarrhea, and abdominal pain may cur. Systemic effects are likely. Because HF is an acid, metabolic acidosis can occur from acute ingestions. Aspiration may lead to pulmonary complications.

Electrolyte disturbance -

Exposure by any route may result in systemic effects, namely, severe hypocalcemia, hypomagnesemia, and hyperkalemia. Hypotension, cardiac dysrhythmias, tetany, seizures, and death may ensue.

Potential Sequelae -

Survivors of severe inhalation injury may suffer residual chronic lung disease. Healing of skin bums caused by concentrated HF may be prolonged, and extensive scarring loss may result. Fingertip injuries are troublesome with persistent pain, bone loss, and nail bed injury. After eye exposure, prolonged or permanent visual defects, blindness, or total eye destruction may occur. After ingestion, damage to the esophagus and stomach may progress for several weeks. Persistent esophageal strictures may result.

Chronic Exposure --

Repeated ingestion of more than 6 mg of fluoride per day may result in mottling of the teeth in developing children, accumulation of fluoride in the bone (fluorosis), and osteosclerosis in adults and children. Long-term HF exposure has been reported to damage the kidneys and liver.

Carcinogenicity -

The question of whether fluoride can cause cancer is controversial. The findings of a recent NTP study in experimental animals is inconclusive.

Reproductive and Developmental Effects -

Fluoride at low doses is thought to be essential for normal fetal development in humans. There have been rare cases of mottling of deciduous teeth in infants born to mothers who had a high daily intake of fluoride during pregnancy. Skeletal abnormalities due to exposure during prenatal development are considered unlikely. Reproductive effects due to HF are unknown.

Prehospital Management

• Victims exposed to only HF gas or vapor do not pose a significant risk of secondary contamination to personnel outside the Hot Zone. However, victims whose clothing or skin is contaminated with HF liquid, solution, or condensed vapors can secondarily contaminate response personnel by direct contact or through off-gassing vapors.
• Hydrogen fluoride is a corrosive chemical that can cause immediate or delayed onset of deep penetrating injury. Absorption of fluoride ion can cause hypocalcemia hypomagnesemia, and hyperkalemia, which can result in cardiac arrest.
• Rapid decontamination is critical. Calcium-containing gels, solutions, and medications are used to neutralize the effects of hydrogen fluoride.

Note. Rescuers should be trained and appropriately attired before entering the Hot Zone. If the proper equipment is not available, or if rescuers have not been trained to use it, call for assistance from a local or regional hazmat team or other properly equipped response organization.

Rescuer Protection -

Rescuers in the Hot Zone should wear self-contained breathing apparatus (SCBA). Chemical-protective clothing and gloves are required if contact with liquid HF, its concentrated vapors, or hydrofluoric acid is possible.

ABCs -

Quickly ensure a patent airway. Stabilize the cervical spine with a collar if trauma is suspected. Administer oxygen and assist ventilation with a bag-valve-mask device if necessary.

Victim Removal -

If victims can walk, lead them out of the Hot Zone to the Decontamination Zone. If victims are unable to walk, remove them on a backboard or gurney. If there is no other means of transport, carefully carry or drag the victim to safety.

Decontamination Zone -

Note. Victims with exposure to only hydrogen fluoride gas or vapor and with no skin or eye irritation do not need decontamination. They may be transferred immediately to the Support Zone.

Rescuer Protection -

Rescuers in the Decontamination Zone should wear self-contained breathing apparatus (SCBA) and chemical-protective clothing and gloves if they will be caring for victims with hydrofluoric acid soaked clothing or skin. If the proper equipment is not available, or if rescuers have not been trained to use it, call for assistance from a local or regional hazmat team or other properly equipped response organization. If the decontamination area is outdoors and has good natural ventilation, a lesser level of respiratory protection may suffice.

ABCs -

Quickly ensure a patent airway. Stabilize the cervical spine with a collar if trauma is suspected. Supplemental oxygen may be administered if available. Establish intravenous access in all seriously symptomatic patients and attach a cardiac monitor. Monitor ECG for prolonged Q-T or QRS interval.

Decontamination -

Rapid decontamination is critical. Remove and double-bag contaminated clothing while flushing exposed skin with water. Patients who are able and cooperative may assist with their own decontamination.

Flush exposed skin and hair with plain water for at least 5 minutes. If available, cover exposed skin with one of the following preparations: (a) calcium-containing slurry or gel (2.5 g calcium gluconate in 100 cc of water-soluble lubricant such as K-Y Jelly) or

(b) aqueous quaternary ammonium salt (Zephiran, 1.3 g in 1 liter of water). (Caution: do not use on face or in eyes.) or
(c) magnesium-containing solution (Maalox, epsom salts).

Flush exposed or irritated eyes with plain water or saline for at least 5 minutes. Remove contact lenses if present.

In case of hydrofluoric acid ingestion, do not induce emesis. Do not administer activated charcoal. If the patient is alert and able to swallow, administer 1 to 2 glasses of water, milk, or a magnesium-containing (Maalox, milk of magnesia) or calcium-containing (Tums) antacid to dilute stomach contents.

Transfer to Support Zone -

As soon as basic decontamination is completed, move the patient to the Support Zone.

Support Zone --

Note. Be certain that patients have undergone basic decontamination ( see Decontamination Zone). Patients who have undergone proper decontamination or have been exposed to only gas or vapor pose no serious risk of causing secondary contamination. Support Zone personnel require no specialized protective gear in such cases.

Quickly ensure a patent airway. Stabilize the cervical spine with a collar if trauma is suspected. Administer supplemental oxygen and assist ventilation with a bag-valve-mask device if necessary. Establish intravenous access in all seriously symptomatic patients and attach a cardiac monitor. Monitor ECG for prolonged Q-T or QRS interval.

Treat bronchospasm with aerosolized bronchodilators.

Treat coma, seizures, and ventricular dysrhythmias according to ALS protocol.

Advanced Treatment -

Intubate the trachea if indicated (severe respiratory distress, apnea, or throat swelling due to ingestion of HF). When endotracheal intubation cannot be performed due to airway obstruction, perform cricothyroidotomy if equipped and trained to do so.

Hypocalcemia (manifested by tetany and dysrhythmias) is probable after ingestion of even small amounts of HF. With medical consultation, treat hypocalcemia with intravenous injections of a 10% solution of calcium gluconate.

If available, administer to inhalation victims 2.5% calcium gluconate (2.5 g of calcium gluconate in 100 mL of water) with oxygen by nebulizer.

Additional Decontamination -

Continue flushing exposed skin for 15 minutes. If either of the treatments recommended in (a) or (b) below is available, water flushing may be reduced to 5 minutes and the treatment should be started immediately. DO NOT USE CALCIUM CHLORIDE for treating skin burns. It will cause extreme pain and may further injure tissues.

(a) Vigorously massage calcium gluconate gel (2.5 g in 100 cc water-soluble lubricant such as K-Y Jelly) into the burned areas. Initially, rubber or latex gloves should be worn by the health care provider to prevent secondary contamination. Continue this procedure until pain is relieved or more definitive care is rendered.

(b) Some investigators recommend immersing the burned area in an iced (use ice cubes, not shaved ice) solution of a quaternary ammonium salt such as Zephiran (1.3 grams of Zephiran per liter of water). Intermittent immersion for at least 2 hours is recommended. Care must be taken to avoid prolonged immersion since severe frostbite injury may result.

If immersion is not practical, soak towels with the Zephiran solution and use them as compresses for the burned area. Change compresses every 2 to 4 minutes. Exercise caution when using these solutions near the eyes since they are irritating to sensitive tissues. Continue Zephiran treatment until pain is relieved or more definitive care is rendered.

If the eyes are still irritated, flush with water or saline for 3 to 5 minutes. Remove contact lenses if present and continue irrigating the eyes with saline via IV tubing for 10 to 15 minutes or until pain and irritation have resolved. In case of hydrofluoric acid ingestion, do not induce emesis. If the patient is alert and able to swallow, administer 1 to 2 glass of water or milk to dilute stomach contents. Do not administer activated charcoal.

Report to the base station and receiving medical facility condition of the patient, treatment given, and estimated time of arrival at the medical facility. If a patient has ingested hydrofluoric acid, prepare the ambulance for possible vomiting of toxic material. Have ready several towels and opened plastic bags to quickly clean up and isolate vomitus.

If possible, consult with the base station physician or regional poison control center for advice regarding triage of multiple victims.

Immediately transport to a medical facility those patients who have inhaled HF and have upper respiratory irritation or other acute symptoms.

Transport to a Medical Facility -

All persons with serious exposure (i.e., eye exposure, fingertip exposure, or skin exposure greater than the total surface area of the palm) or any evidence of bums (e.g., erythema, pain, or blisters) should be transported to a hospital as soon as possible. Continue skin/eye irrigation or treatment during transport.

Multi-casualty Triage --

Inhalation Exposure -

Patients who have had skin or eye contact with HF should be brought to the attention of a physician as soon as possible since they may have delayed pain and systemic complications.

Skin/Eye Contact -

In cases of ingestion, patients should be transported to a hospital without delay. Watch patients carefully since systemic effects are likely to occur.

Ingestion -

Person s who have had minor or brief exposure to only HF gas or vapor and are initially asymptomatic are not likely to develop complications. After recording their names, addresses, and telephone numbers, they may be released from the scene with follow-up instructions.

Emergency Department Management

• Victims exposed to only HF gas or vapor do not pose a significant risk of secondary contamination to personnel outside the Hot Zone. However, victims whose clothing or skin is contaminated with HF liquid or solution can secondarily contaminate personnel by direct contact or through off-gassing vapor.
• Hydrogen fluoride is a corrosive chemical that can cause deep penetrating injury. Absorption of fluoride ion can result in hypocalcemia and cardiac arrest. Hypocalcemia should be considered a risk in all instances of inhalation or ingestion and whenever skin burns exceed 25 in(2) (an area about the size of the palm).
• Because of HF's rapid skin penetration and the serious toxicity of the fluoride ion, rapid decontamination is critical. Calcium-containing gels, solutions, and medications can be used to neutralize the fluoride ion. The intense pain of HF burns should not be suppressed with local anesthetics since the degree of pain is an indicator of treatment efficacy.

Note. Patients exposed to only hydrogen fluoride gas or vapor and with no skin or eye irritation do not need decontamination. They can be transferred immediately to the Critical Care Area. Other patients will require decontamination as described below. Since contacting HF-soaked clothing or skin can cause burns, ED personnel should don chemical resistant jumpsuits (e.g., of Tyvek, Saranex) or butyl rubber aprons, multiple layers of latex gloves, and eye protection.

ABCs -

Evaluate and support airway, breathing, and circulation. Watch for signs of airway compromise. Monitor cardiac rhythm.

Basic Decontamination -

Rapid skin decontamination is critical. If the patient's clothing is soaked, remove and double-bag the clothing while flushing the skin with copious water (preferably under a shower).

Remove contact lenses and irrigate exposed eyes with water for at least 15 minutes or until the pH of the conjunctival fluid is above 7. An ophthalmic anesthetic, such as 0.5% tetracaine, may be necessary to alleviate blepharospasm, and lid retractors may be required to allow adequate irrigation under the eyelids.

Critical Care Area --

Note. Be certain that decontamination has been carried out. See Decontamination Area.

ABCs -

Evaluate and support ABCs. Watch for signs of airway compromise. Monitor heart, renal, and liver functions. Hypocalcemia may cause prolonged Q-T interval and cardiac rhythm abnormalities. Calcium gluconate (2.5 grams of calcium gluconate in 100 mL of water) may be administered with oxygen by nebulizer to victims with severe respiratory distress.

Inhalation Exposure -

Pulmonary edema or edema of the upper airway may occur. Observe the patient for at least 24 hours and monitor with repeated chest examinations, blood gases, and other appropriate tests. Follow up as clinically indicated.

Skin Contact -

If blisters have formed, they should be opened and drained and necrotic tissue debrided prior to treatment; early debridement may facilitate healing.

Two topical treatments that are generally recommended are discussed in (a) and (b) below.

(a) Continuously massage calcium gluconate gel (2.5 grams in 100 mL water soluble lubricant such as K-Y Jelly) into the burned area until the pain is relieved. If used as definitive treatment, the gel should be applied 4 to 6 times daily for 3 to 4 days. Initially, rubber gloves should be worn to protect the health care providers' fingers from secondary contamination. If some relief of pain is not obtained within 30 to 60 minutes, consider Zephiran soaks or calcium gluconate injections.

(b) Some investigators recommend immersing the burned area in an iced (use ice cubes, not shaved ice) solution of a quaternary ammonium salt such as Zephiran (1.3 grams of Zephiran per liter of water). Intermittent immersion for at least 2 hours is recommended. If pain recurs after treatment is stopped, immersion should be continued for another 2 hours. Total treatment of 4 to 6 hours is usually required. If immersion is impractical, compresses soaked with the Zephiran solution and changed every 2 to 4 minutes can be used.

Care must be taken that victims do not suffer frostbite from prolonged immersion. Because quaternary ammonium solutions are very irritating to sensitive tissues, they should not be used on the face, particularly around the eyes or on other sensitive areas.

Severe Burns -

Large burns or deeply penetrating bums (from delayed treatment or exposure to HF concentrations greater than 50%) may require injections of sterile aqueous calcium gluconate into and around the burned area. Authorities in industry currently recommend injections of 5 % calcium gluconate solution using a small gauge needle (#30). Do not inject more than 0.5 mL per cm(2) of affected skin surface. No local infiltration of anesthetic should be used, but in the case of severe bums, regional or general anesthesia may be considered.

DO NOT USE CALCIUM CHLORIDE for treating skin burns. It will cause extreme pain and may further injure tissues.

Hand Exposures -

Subungal (under the nail) bums often do not respond to immersion treatment, The treatments for hand burns require expert assistance; obtain consultation with a poison center, medical toxicologist, or hand surgeon.

Calcium gluconate in very small doses can be injected into the fingers. In some cases, burr holes must be drilled in the nail or the nail must be split or removed (using regional anesthesia) to permit adequate contact with the sequestering agent. Care must be used since multiple injections into the fingers can lead to pressure necrosis. Patients who have received multiple injections of calcium gluconate in skin that has compromised integrity may have an increased risk of infection. Consider the use of antibiotic creams such as Silvadene or Garamycin in these cases.

An alternative to intradermal injection is infusion of calcium gluconate or calcium chloride (10 mL of 10% solution in 40 mL of normal saline) into the radial artery over 4 hours. (A recent study in which this alternative was used for HF burns can be found in Siegel DC, Heard JM. Intra-arterial calcium infusion for hydrofluoric acid burn. Aviation, Space, and Environmental Medicine, 1992;March:206-211.)

Eye Contact -

Do not use oils, salves, or ointments for injured eyes. Do not use Zephiran or the gel form of calcium gluconate in eyes as described for skin.

Irrigate exposed eyes with a 1% aqueous solution of calcium gluconate (50 mL Of 10% solution in 450 mL of sterile saline) using a nasal prong or Morgan Therapeutic Lens. Up to 500 mL over 1 to 2 hours may be used. If calcium gluconate is not available, use normal saline for irrigation.

A topical anesthetic can minimize the tendency for eyelid closure and facilitate insertion of an irrigation lens. One or two drops of proparacaine or tetracaine will usually provide rapid-onset ocular anesthesia for 20 minutes to an hour. If exposure was minor, perform visual acuity testing and examine the eyes for corneal damage using fluorescein and a slit lamp. In cases of significant exposure, an ophthalmologist should be consulted immediately. Do not give emetics and do not administer activated charcoal.

Ingestion -

If it has not been administered previously and if the patient is conscious and alert, immediately give 1 to 3 glasses of water to dilute the acid. Orally administer a one-time dose of several ounces of Mylanta, Maalox, or milk of magnesia; the magnesium in these products may act to chemically bind the fluoride in the stomach. Consider gastric lavage using a small lumen tube. Consider endoscopic examination to evaluate the extent of damage. Extreme throat swelling may cause airway obstruction, which may require endotracheal intubation or cricothyroidotomy.

Systemic Toxicity -

Serum calcium, potassium, and magnesium levels must be monitored. Treat hypocalcemia using calcium gluconate infusions. Infusions can be repeated until serum calcium, ECG changes or symptoms improve. Treat hypomagnesemia with 1 to 2 grams of magnesium.

Disposition and Follow-up -

Patients who fall to respond to treatment with diminished pain and those with respiratory distress, ingestion exposure, finger-tip or eye bums, or significant skin burns should be admitted to an intensive care unit and carefully watched for 24 hours. (Significant skin burns are those covering an area greater than the palm of a hand, or causing skin changes, or producing pain within 1 hour of exposure.) ECG monitoring may aid in determining treatment need and effectiveness.

Patient Release -

Eye contact victims with no signs of irritation after treatment do not require hospitalization.

Patients in the ED with bums covering less than an area equivalent to the palm of the hand and with normal serum calcium level s, who have responded to treatment, can be discharged for outpatient follow-up after remaining stable for at least 6 hours. They should be advised to seek medical care promptly if pain recurs (see the reverse side of Hydrogen Fluoride--Patient Information Sheet).

Reporting --

If a work-related incident has occurred, you may be legally required to file a report; contact your state or local health department.

Other persons may still be at risk in the setting where this incident occurred. If the incident occurred in the workplace, contact the employer or OSHA for assistance in evaluating workplace conditions. An appropriate public agency can be notified if a public health risk exists. If appropriate, inform patients that they may request an evaluation of their workplace from NIOSH. See Appendix Ill for a list of these and other agencies that may be of assistance.

Hydrogen Fluoride and Hydrofluoric Acid Patient Information Sheet

What is hydrogen fluoride?

Hydrogen fluoride (HF) is a colorless, highly irritating gas with a pungent odor. It easily dissolves in water to form hydrofluoric acid. In addition to some industrial products, over-the- counter products that contain HF include rust removers, water spot removers, and chrome cleaners.

What immediate health effects may result from exposure to hydrogen fluoride?

Most poisoning occurs when hydrogen fluoride gets on the skin or in the eyes. Concentrated HF solutions can cause severe deep and disfiguring burns and absorption of the chemical into the body can cause the heart to beat irregularly and death. Although exposure to concentrated HF solutions (greater than 60%) causes immediate burning, exposure to more dilute solutions (less than 20%) may cause few or no symptoms at first but may be followed by severe pain later. Drinking hydrofluoric acid can cause severe bums to the throat and stomach, and even death.

Injury also can occur from breathing HF gas or the vapor from concentrated HF solutions. With small doses, few or no symptoms may occur at first. With larger doses, however, most people will notice a sharp odor and their skin, eyes, nose, and throat will bum. Breathing high concentrations of HF vapor can cause rapid death from throat swelling or from chemical burns to the lungs.

What is the treatment for hydrogen fluoride poisoning? Patients who have experienced serious symptoms (such as severe or persistent coughing or skin or eye burns) may need to be hospitalized for several hours. Calcium- or magnesium-containing medicines may be used to treat the skin, and doctors may even inject calcium-containing medicines into burned areas or into the blood to neutralize the fluoride that causes the injury.

Are any future health effects likely to occur?

After a single, small exposure, no delayed or long-term effects are likely to occur. After a severe exposure, you may not notice any symptoms for up to 36 hours. The reverse side of this page lists some signs and symptoms to watch for--if any of them occur, seek medical care. Scarring may occur from skin contact with HF.

What tests can be done ira person has been exposed to HF? The doctor may order blood tests, urine tests, chest X ray, and a heart monitoring test to see if damage has been done to the heart, lungs, or other organs. Testing is not needed in every case. If HF contacts the eyes, the doctor may put an orange dye into them and examine them with a magnifying lamp. If hydrofluoric acid is swallowed, the doctor may administer a solution containing calcium or magnesium.

Where can more information about hydrogen fluoride be found? More information about hydrogen fluoride or hydrofluoric acid may be obtained from your regional poison control center, your state, county, or local health department; the Agency for Toxic Substances and Disease Registry (ATSDR); your doctor; or a clinic in your area that specializes in occupational and environmental health. If the exposure happened at work, you may wish to contact the Occupational Safety and Health Administration (OSHA) or the National Institute for Occupational Safety and Health (NIOSH). Ask the person who gave you this form for help in locating these telephone numbers.

Hydrogen Fluoride and Hydrofluoric Acid Follow-up Instructions

--Follow only the instructions checked below. Please bring this page with you to your next appointment.

( ) Call your doctor or the Emergency Department if you develop any of the
following symptoms within the next 3 days:
* difficulty breathing or shortness of breath
* chest pain
* wheezing
* hoarseness, high-pitch voice, or difficulty speaking
* fever
* any skin changes or discharge where skin is burned
* belly pain, vomiting, diarrhea
( ) No follow-up appointment is necessary unless you develop any of the
symptoms described above.
( ) Call for an appointment with Dr. _________ in the practice of_________.
When you call for your appointment, please tell the receptionist/nurse that
you were treated in the Emergency Department at__________________ Hospital by
__________ and were advised to be seen again in __ days.
( ) Return to the Emergency Department/__________Clinic on (date)__________
at____ AM/PM for a follow-up examination.
( ) Do not perform vigorous physical activities for __ days.
( ) You may resume everyday activities including driving and operating
machinery.
( ) Do not return to work for __ days.
( ) You may return to work on a limited basis. See instructions below.
( ) Avoid exposure to cigarette smoke for 72 hours since smoke may worsen
injury to your lungs.
( ) Avoid drinking alcoholic beverages or taking aspirin for 24 hours since
these substances may aggravate injury to your stomach lining or may have
other effects.
( ) You may continue taking the following medication(s) that your doctor(s)
prescribed for you:
( ) Other instructions:
Signature of patient ______Date _______
Signature of physician _______Date __________

Above courtesy of C.D.C.