Hydrogen Chloride 

### Hydrogen Chloride (HCl) CAS 7647-01-0; UN 1050 (anhydrous), UN 1789 (solution), UN 2186 (refrigerated liquefied gas) Synonyms for an aqueous solution of hydrogen chloride include chlorohydric acid, hydrochloric acid, and muriatic acid.

C Persons exposed only to hydrogen chloride gas do not pose significant risks of secondary contamination. Persons whose clothing or skin is contaminated with hydrochloric acid can cause secondary contamination by direct contact or through off-gassing vapor.

C Hydrogen chloride is a colorless, corrosive, nonflammable gas that fumes in air. It has a characteristic pungent odor. It is heavier than air and may accumulate in low-lying areas.

C Hydrogen chloride is not absorbed through the skin, but when hydrogen chloride gas comes in contact with moisture, it forms hydrochloric acid, which is corrosive and can cause irritation and burns.


### Descri ption At room temperature, hydrogen chlorid e is a colorless to slightly ye llow gas with a pungent odor. On exposure to air, the ga s forms dense white vapors due to condensation with atmospheric moisture. The vapor is corrosive, and air concentrations above 5 ppm can cause irritation. Hydrogen chloride is available commerciall y as an anhydrous gas or as aqueous solutions (hydrochloric acid). Commercia l concentr ated hydrochloric acid contains 36% to 38% hydrogen chloride in wa ter. Aqueous solutions generally are colorless but ma y be yellow due to traces of iron, chlorine, and organi c impurities. 

### Routes of Exposure
Inhalation Inhalation is an important route of exposure to hydroge n chlo ride. Its odor and highly irritating properties generall y provi de adequate warning for acute, high-level exposures

. However, only 50% of exposed persons can perceive hydrogen chloride’s odor at the OSHA permissible ex posure limit (5 ppm), and od or may not provide adequate warning in th e workplace . Hydrogen chloride vapor is h eavier than air and may cau se asphyxiation in enclosed, poorly ventilated, or low-lyin g areas.

ATSDR • General Information 1Hydrogen Chloride Children exposed to the same levels of hydrogen chloride a s adul ts may receive larger dose because they have greater lun g su rface area:body weight ratios and increased minut e volumes:weight ratios. In addition, they may be exposed t o high er levels than adults in the same location because of thei r short stature and the higher levels of hydrogen chloride foun d nearer to the ground. Skin/Eye Contact Hy drogen chloride is not absorbed through the skin. Direc t contact with aqueous solutions of hydrogen chloride or wit h concentrated vapor can cause severe chemical burns.
Childrenare more vulnerable to toxicants affecting the ski n because of their r elatively larger surface area:body weight ratio. Ingestion Ing estion of concentrated hydrochloric acid can cause sever e corrosive injury to the lips, mouth, throat, esophagus, an d stomach. 

### Sources/Uses Hyd rogen chloride is produced commercially by any of th e following reactions: heated hydrogen gas with calcium chloride, sulfuric acid with sodium chloride, sodium chloride with sulfur diox ide and steam, and hydrogen burned in chlorine. Hydrogen chloride can be formed during the combustion of many plastics. Hydrochloric acid (muri atic acid) is a component of commercial chemicals used to clean and disinfect swimming pools. Hyd rogen chloride is used for cleaning, pickling, an d electroplating meta ls; in refining mineral ores; in petroleum well extraction; in leather tanning; and in the refining of fats, soaps, and edible oils. It is also used in producing polymers an d plastics, rubber, fertilizers, dyes, dyestuffs, and pigments. 

### Standards and Guidelines OSHA PEL (permissible exposure limit) = 5 ppm (ceiling)
NIO SH IDLH (immediately dangerous to life or health) = 50 ppm
AIH A ERPG-2 (emergency response planning guideline ) (maximum airborne concentration below wh ich it is believed that nearly all ind ividuals could be exposed for up to 1 hour without exp eriencing or developing irreversible or other serious healt h effects or symptoms which could im pair an individual’s ability to take protective action) = 20 ppm 

### Physical Properties Description : Colorless-to-slightly yellow gas

2 General Information • ATSDRHydrogen Chloride Warning properties: S harp, choking odor. Air odor threshold is 0.77 ppm, but only 50% of distracted exposed persons ca n perceive hydrogen chloride’s odor at 5 ppm. Molecular weight : 36.5 daltons Boiling point (760 mm Hg): = -121 E F (-85 E C) Freezing point: -174 E F (-114 E C) Vapor pressure : 30,780 mm Hg at 68 E F (20 E C) Gas density: 1.3 (air = 1) Water solubility: 67% at 68 E F (20 E C) Flammability: Not flammable 

### Incompatibilities Hydrogen chloride is highly corrosive to most metals. It als o reacts with hydroxides, amines, and alkalies.

ATSDR • General Information 3Hydrogen Chloride

4 General Information • ATSDRHydrogen Chloride 

### Health Effects

• Concentrated hydrogen chloride can be corrosive to the skin, eyes, nose, mucous membranes, and respiratory and gastrointestinal tracts.

• Inhalation of hydrogen chloride can lead to pulmonary edema. Ingestion can cause severe injury to the mouth, throat, esophagus, and stomach.

• Other effects of exposure include shock, circulatory collapse metabolic acidosis, and respiratory depression.



### Acute Exposure Hydr ogen chloride is a strong mineral acid; its corrosive an d irrita nt properties are the primary concern in both acute an d chronic exposures.
Childre n do not always respond to chemicals in the same wa y that adults do. Different protocols for managing their care may be needed. Respiratory Hydrog en chloride gas is intensely irritating to the mucou s me mbranes of the nose, throat, and respiratory tract. Brie f exp osure to 35 ppm causes throat irritation, and levels of 50 to 100 ppm are barely tolerable for 1 hour. The greatest impact is on the upper respiratory tract; exposure to high concentrations ca n rapidly lead to swelling and spasm of the throat an d suffocation.
Most seriously exposed persons have immediate onset of rapid brea thing, blue coloring of the skin, and narrowing of th e bronchioles. P atients who have massive exposures may develop an accumulation of fluid in the lungs.
Ex posure to hydrogen chloride can lead to Reactive Airwa y Dy sfunction Syndrome (RADS), a chemically- or irritant

induced type of asthma. Children may be more vulnerable to corrosive agents than adults becaus e of the relatively smaller diameter of their airways

. Childrenmay also be more vulnerable to gas exposure because of increased minute venti lation per kg and failure to evacuate an area promptly when exposed.
Metabolic A rare and unusual complication of ingestion of high levels o f hydrogen chloride is an increase in the concentration of chloride ions in the blood, causing an acid-base imbalance.
ATSDR • Health Effects 5Be cause of their higher metabolic rates, children may be mor e vulnerable to toxicants interfering with basic metabolism.
Dermal Deep bu rns of the skin and mucous membranes are caused b y cont act with concentrated hydrochloric acid or hydroge n chlorid e gas; disfiguring scars may result. Contact with les s concentrated acid or with vapor o r mist can cause redness of the skin and mild inflammation. Because of their relatively larger surface area:body weight ratio, children are more vulnerable to toxicants affecting the skin. Hydrogen Chloride

Ocular Exposure of the eyes to concentrated hydrogen chloride vapor or hydrochloric ac id can cause corneal cell death, cataracts, and glaucoma. Exposure to dilute solutions can cause stinging pain and injuries such as ulcers of the eye surface. Gastrointestinal Ingesting concentrated hydrochloric acid can cause pain, difficulty swallowing, nausea, and vomiting. nausea, and vomiting. Ingestion o f concentrated hydrochloric acid can also caus e severe c orrosive injury to the mouth, throat esophagus, an d sto mach, with bleeding, perforation, scarring, or strictur e formation as potential sequelae. Hepatic Liver damage and ischemia may be observed. Renal
Cardiovascular Renal failure and nephritis may occur. Ingestion of concentrated hydrochloric acid or massive ski n exposu re to either hydrochloric acid or hydrogen chloride ga s may c ause low blood pressure as a result of gastrointestina l bleeding or fluid displaceme nt. After acute exposure, pulmonary function generally returns to baseline in 7 to 14 days. Potential Sequelae Althoug h complete recovery is usual, symptoms and prolonged pul monary deficits can persist. Patients may develop Reactiv e Airways Dysfunction Syndrome (RADS).

Pa tients who have ingested hydrochloric acid may experienc e scarr ing of the esophagus or stomach, which can caus e narrowing, difficulty swallowing, or gastric outlet obstruction.


### Chronic Exposure gastric outlet obstruction. Chronic or prolonged exposure to hydrogen chloride gas (above the OSHA PEL) or to mist has been associated with changes in p u lmonary function, chronic inflammation of the bronchi, nasal ulceration, and sympto ms resembling acute viral infection of the upper respiratory tract as well as inflammation of the skin , discoloration and erosion of dental enamel, and inflammation of the eye membrane. Chlorosis may occur with prolonged exposure.

6 Health Effects • ATSDRHydrogen Chloride Carcinogenicity Hy drogen chloride has not been classified for carcinogeni c effects. Reproductive and Developmental Effects Some r eproductive hazards of hydrogen chloride to humans ar e unknown. Few studies have been directed a t reproductive effects in exp erimental animals exposed to hydrogen chloride. No data were located pertaining to maternal transfer of hydrogen chloride thro ugh the placenta or in breast milk Hydrogen chloride is not included in Reproduct ive and Developmental Toxicants, a 1991 report publishe d by the U.S. General Accounting Office (GAO) that lists 30 chemicals of concern because of widel y acknowledged reproductive and developmental consequences. Fetotoxicity, developmental abnormalities, and possible resistance to hydrogen chloride by inhalation during pregnancy have been noted. No data about possible male reproductive effects is available.

ATSDR • Health Effects 7Hydrogen Chloride

8 Health Effects • ATSDRHydrogen Chloride 

### Prehospital Management

C Victims exposed only to hydrogen chloride gas and whose skin and clothing appear dry do not pose risks of secondary contamination to rescuers. However, victims exposed to hydrochloric acid or hydrogen chloride whose clothing or skin is moist orwet can secondarily contaminate response personnel by direct contact or through offgassing vapor.

C High concentrations of hydrogen chloride can cause corrosive injury to all exposed body tissues. When inhaled, it can result in upper respiratory tract irritation, leading to laryngeal edema, laryngeal spasm, and asphyxia. Concentrated hydrochloric acid causes similar corrosive injury to the skin and, if ingested, can cause severe corrosive injury to the mouth, throat, esophagus, and stomach.

C There is no antidote for hydrogen chloride poisoning. Treatment consists of support of respiratory and cardiovascular functions.


### Hot Zone Res cuers should be trained and appropriately attired befor e entering the Hot Zone. If the proper equipment is not available, or if rescuers have not been trained in its use, assistance should be obtained from a local or regional HAZMAT team or othe r properly equipped response organization.
Rescuer Protection Hydrogen chloride gas is a severe respiratory-tract and ski n irrit ant that forms a strong acid (hydrochloric acid) on contac t with water.
Re spiratory Protection : Positive-pressure, self-containe d breat hing apparatus (SCBA) is recommended in respons e situations that involve exposure to potentially unsafe levels o f hydrogen chloride. Sk in Protection : Chemical-protective clothing is recommended because hydrogen chloride can cause skin irritation and burns. ABC Reminders Quickl y access for a patent airway, ensure adequate respiration and pulse. If trauma is suspected, maintain cervica l im mobilization manually and apply a cervical collar and a backboard when feasible. Victim Removal If v ictims can walk, lead them out of the Hot Zone to th e Decontamination Zon e. Victims who are unable to walk may be removed on backboards or gurneys; if these are not available , carefully carry or drag victims to safety.

ATSDR • Prehospital Management 9Hydrogen Chloride Cons ider appropriate management of chemically contaminate d children, such as measures to redu ce separation anxiety if a child is separated from a parent or other adult. 

### Decontamination Zone Victims exposed only to hydrogen chloride gas w ho have no skin or eye irritation do not need decontamination; they may b e transferred i mmediately to the Support Zone. All others require decontamination as described below.
Rescuer Protection If exp osure levels are determined to be safe, decontaminatio n may be conducted by personnel wearing a lower level o f protection than that worn in the Hot Zone (described above). ABC Reminders Quickl y access for a patent airway, ensure adequate respiration and pulse. Stabilize the cervical spine with a collar and a backboard if trauma is suspected. Administer supplementa l oxygen as required. Assist ventilation with a bag-valve-mas k device if necessary.
Basic Decontamination Victims who are able may assist with their o wn decontamination. Remove conta minated clothing while flushing exposed skin and hair with water for 3 to 5 minutes, wash thoroughly with soa p and water. Use caution to avoid hypothermia whe n decontaminating children or the elderly. Use bl ankets or warmers whe n appropriate. Double-bag contaminated clothing an d personal belongings.
Fl ush exposed or irritated eyes with tepid plain water or salin e for 15 minutes. Eye irrigation should be carried ou t simu ltaneously with other basic care and transport. Remov e contact lenses if easily removable without additional trauma to the eye. In cases of ingestion, do not induce e mesis

. Do not administer acti vated charcoal or attempt to neutralize stomac h contents . Victims who are conscious and able to swallow should be given 4 to 8 ounces o f water or milk. (Children’s dose is 2 to 4 ounces.)
Cons ider appropriate management of chemically contaminate d children, such as measures to redu ce separation anxiety if a child is separated from a parent or other adult. If possible, see k assistance from a child separation expert. Transfer to Support Zone As soo n as basic decontamination is complete, move the victim to the Support Zone.

10 Prehospital Management • ATSDRHydrogen Chloride 

### Support Zone Be certai n that victims have been decontaminated properly (see Decontamination Zone above). Victims who have undergon e decontamination or who have been expos ed only to gas and who have no symptoms of skin or eye irritation pose no serious risk of secondary contamination. In such cases, Support Zon e personnel require no specialized protective gear.
ABC Reminders Quickly access for a patent airway. If trauma is suspected , mai ntain cervical immobilization manually and apply a cervica l collar and a backboard when feasible. Ensure adequat e resp iration and pulse. Administer supplemental oxygen a s requir ed and establish intravenous access if necessary. Place on a cardiac monitor.
Additional Decontamination Continue irrigating exposed skin and eyes, as appropriate. In cases of ingestion, do not induce e mesis

. Do not administer acti vated charcoal or attempt to neutralize stomac h contents . Adu lt victims who are conscious and able to swallow should be given 4 to 8 ounces of w ater or milk, if it has not been gi ven previously, to flush residual acid from the esophagus and to dil ute stomach contents. Children should receive half of th e adult dose.
Advanced Treatment In cases of respiratory compromise secure ai rway and respiration via endotracheal intubation. If not possible, perfor m cricothyroidotomy if equipped and trained to do so.
Treat patients who have bronchospasm with aerosolize d bro nchodilators. The use of bronchial sensitizing agents i n si tuations of multiple chemical exposures may pose additiona l ri sks. Consider the health of the myocardium before choosin g wh ich type of bronchodilator should be administered. Cardia c sensiti zing agents may be appropriate; however, the use o f cardia c sensitizing agents after exposure to certain chemical s may pose enhanced risk o f cardiac arrhythmias (especially in the elderly). Sympathomimetic bronchodilators gen erally will reverse bronchospasm in patients exposed to hydrogen chloride.
Consider racemic epinephrine aerosol for children who develop stridor. Dose 0.25–0.75 mL of 2.25% racemic epinephrin e solution in 2.5 cc water, repeat every 20 minutes as needed , cautioning for myocardial variability.
Patient s who are comatose, hypotensive, or are having seizures or cardiac ar rhythmias should be treated according to advanced life support (ALS) protocols.

ATSDR • Prehospital Management 11Hydrogen Chloride Transport to Medical Facility On ly decontaminated patients or patients not requirin g decon tamination should be transported to a medical facility

. “Body bags” are not recommended. Rep ort to the base station and the receiving medical facility the cond ition of the patient, treatment given, and estimated time of arrival at the medical facility. If hydrochloric acid has b een ingested, prepare the ambulance in case the victim vomits to xic material. Have ready several towels and open plastic bags to quickly clean up and isolate vomitus. 

### Multi-Casualty Triage Consult with the base station physician or the regional poiso n control center for advice regarding triage of multiple victims. Patients with evidence of significant exposure such as skin or eye irritation, pain, o r breathing difficulties should be transported to a medical facility for evaluation. Others may be discharged from the scene after their names, addresses, and telephone number s are r ecorded. Those discharged should be advised to see k medic al care promptly if symptoms develop (see Patien t Information Sheet below).

12 Prehospital Management • ATSDRHydrogen Chloride 

### Emergency Department Management

C Patients exposed only to hydrogen chloride gas whose clothing and skin are dry do not pose a risk of secondary contamination. Hospital personnel can be secondarily contaminated by patients exposed to hydrochloric acid either by direct skin contact or through inhalation of vapor off-gassing from heavily soaked clothing or skin. Patients do not pose contamination risks after contaminated clothing is removed and the skin is washed.

C High concentrations of hydrogen chloride causes corrosive injury to all exposed body tissues. When inhaled, it can result in upper respiratory tract irritation, leading to laryngeal edema, laryngeal spasm, and asphyxia. Concentrated hydrochloric acid causes similar corrosive injuries to exposed tissues and, if ingested, can cause severe corrosive injury to the mouth, throat, esophagus, and stomach.

C There is no antidote for hydrogen chloride poisoning. Treatment consists of support of respiratory and cardiovascular functions.



### Decontamination Area Previously decontaminated patients and patients exposed only to hydrogen chloride gas who ha ve no skin or eye irritation may be transferred immediately to the Criti cal Care Area. Others require decontamination as described below. Hospital personnel should don rubber gl oves, rubber aprons, and eye protection before treating patients who are wet wit h hydrochloric acid.
Be awar e that use of protective equipment by the provider may ca use fear in children, resulting in decreased compliance wit h further management efforts. Because of their relatively larger surface area:body weight ratio, children are more vulnerable to toxicants affect ing the skin. Also, emerg ency room personnel should examine children’s mouth s because of the frequency of hand-to-mouth activity amon g children. ABC Reminders Evaluate and support airway, breathing, and cir culation. Children may be more vulner able to corrosive agents than adults because of

the smaller diameter of their airways. In cases of respiratory compromise secure airway and respiration via endotrachea l intubation. If not possible, surgically create an airway.
Treat patients who have bronchospasm with aerosolize d bro nchodilators. The use of bronchial sensitizing agents i n

ATSDR • Emergency Department Management 13Hydrogen Chloride si tuations of multiple chemical exposures may pose additiona l ri sks. Consider the health of the myocardium before choosin g wh ich type of bronchodilator should be administered. Cardia c sensiti zing agents may be appropriate; however, the use o f cardia c sensitizing agents after exposure to certain chemical s may pose enhanced risk o f cardiac arrhythmias (especially in the elderly ). Hydrogen chloride poisoning is not known to pos e additional risk during the use of bronchial or cardiac sensitizing agents. Sympathomimeti c bronchodilators generally will reverse bronchospasm in patients exposed to hydrogen chloride.
Consider racemic epinephrine aerosol for children who develop stridor. Dose 0.25–0.75 mL of 2.25% racemic epinephrin e solution in 2.5 cc water, repeat every 20 minutes as needed , cautioning for myocardial variability.
Pat ients who are comatose, hypotensive, or having seizures o r car diac arrhythmias should be treated in the conventiona l manner. Basic Decontamination Patients who are able may assist with their own decontamination. Remo ve and double-bag contaminated clothing and persona l belongings.
Flush exposed skin and hair with water for 3 to 5 minute s (prefe rably under a shower). Wash thoroughly with soap an d water, rinse thoroughly with water. Use caution to avoi d hypothermia when decontaminating children or the elderly. Use blankets or warmers when appropriate.
Flush exposed eyes with plain water or saline for at leas t 15 minutes. Remove contact lenses if easily removable without ad ditional trauma to the eye. Continue irrigation whil e transporting the patient to the Critical Care Area. In cases of ingestion, do not induce e mesis

. Do not administer acti vated charcoal or attempt to neutralize stomac h content s
. If it has not been given previously, administer 4 t o 8 ounce s of water or milk to adults to flush residual acid fro m the esop hagus and to dilute stomach contents. (Children’s dose is 2 to 4 ounces.) 

### Critical Care Area Be certain that appropriate decontaminat ion has been carried out (see Decontamination Area above).

14 Emergency Department Management • ATSDRHydrogen Chloride ABC Reminders Evalu ate and support airway, breathing, and circulation as i n AB C Reminders above. Children may be more vulnerable t o corros ive agents than adults because of the relatively smalle r diame ter of their airways. Establish intravenous access i n ser iously ill patients if this has not been done previously

. Continuously monitor cardiac rhythm.
Pa tients who are comatose, hypotensive, or have seizures o r car diac arrhythmias should be treated in the conventiona l manner. Inhalation Exposure Admi nister supplemental oxygen by mask to patients who have re spiratory symptoms. Treat patients who have bronchospas m wi th aerosolized bronchodilators. The use of bronchia l se nsitizing agents in situations of multiple chemical exposure s may pos e additional risks. Consider the health of th e myo cardium before choosing which type of bronchodilato r should be administered. Cardiac sensitizing agents may b e appropriate; howev er, the use of cardiac sensitizing agents after exposure to certain chemicals may pose enhanced risk of cardiac arr hythmias (especially in the elderly). Sympathomimeti c bronchodilato rs generally will reverse bronchospasm in patients exposed to hydrogen chloride.
Consider racemic epinephrine aerosol for children who develop stridor. Dose 0.25–0.75 mL of 2.25% racemic epinephrin e solution in 2.5 cc water, repeat every 20 minutes as needed , cautioning for myocardial variability.
Obse rve patients for at least 24 hours, repeating appropriat e tests and chest examinations as needed. Follow-up as clinically indicated.
Som e authorities recommend treatment with high doses o f c o rticosteroids for patients who have high-dose exposures, but the valu e of this treatment is questionable and unsupported b y clinical studies. Skin Exposure If the skin was in contact with co ncentrated hydrochloric acid or hydrogen chloride gas or mists, chemical burns may occur, treat as thermal burns. Because of their relatively larger surface area:body weight ratio, children are more vulnerable to toxicants affecting the skin.

ATSDR • Emergency Department Management 15Hydrogen Chloride Eye Exposure Continue irrigati ng for at least 15 minutes or until the pH of the conjunc tival fluid has returned to normal. Test visual acuity

. Exam ine eyes for corneal damage and treat appropriately

. Imme diately consult an ophthalmologist for patients who hav e corneal injuries. Ingestion Exposure Do not induce emes is

. Do not administer activated charcoal or attempt to neutralize stomach content s . Immediate dilution with 4 to 8 o unces of water or milk may be beneficial (pediatric dose 2 to 4 ounces) for alert patients who can swallow.
Consid er endoscopy to evaluate the extent of gastrointestina l tract injury. Extreme throat swelling may require endotrachea l intuba tion or cricothyroidotomy. Gastric lavage is useful i n certain circumstances to remove cau stic material and prepare for en doscopic examination. Consider gastric lavage with a smal l nasog astric tube if: (1) a large dose has been ingested; (2) th e patient’s condition is evaluated within 30 minutes; (3) the patient has oral lesions o r persistent esophageal discomfort; and (4) the lavage can be administered within 1 hour of ingestion. Care must be taken when placing the gastric tube be cause blind gastric-tube placement may further injure t he chemically damaged esophagus or stomach.
Becau se children do not ingest large amounts of corrosiv e materia ls, and because of the risk of perforation from N G in tubation, lavage is discouraged in children unless performe d under endoscopic guidance.
Toxic vomitus or gastric washings should be isolated (e.g., b y attachi ng the lavage tube to isolated wall suction or anothe r closed container).
The use of corticosteroids to prevent acid-induced strictures is questionable and unsupported by clinical studies. Antidotes and Other Treatments Laboratory Tests There is no antidote for hydrogen chloride poisoning.
The di agnosis of acute hydrogen chloride toxicity is primaril y clinical, based on symptoms of the corrosive action of the gas or acid. Routine laboratory studies for all exposed patients include CBC, glucose, and electrolyte determinatio ns. Monitor acid-base status in patients who have ingested hydrochloric acid. I f respiratory-tract irritation is present, monitor with ches t radiography and pulse oximetry (or ABG measurements).

16 Emergency Department Management • ATSDRHydrogen Chloride Th ere is no biologic test specific for systemically absorbe d hydrogen chloride. 

### Disposition and Follow-up Patients who develop serious signs or symptoms of hydroge n chloride exposure should be hospitalized and observed closel y for 4 to 6 hours or until asymptomatic. Delayed Effects Delay ed effects are unlikely in patients who have mino r symp toms that resolve quickly. However, symptoms can b e delayed for 1 to 2 days.
Patient Release Patie nts who have had minor exposure and who ar e asymptomatic 4 to 6 hours after exposure may be discharged and advised to seek medical care promptly if symptoms develop (see the Hydrogen Chloride—Patient Information Sheet below). Follow-up Obtain the name of the patient’s primary care physician so that th e hospital can send a copy of the ED visit to the patient’ s doctor.
Pati ents who have inhaled significant amounts of hydroge n chloride should be monitored with pulmonary function tests

. Patien ts should also be monitored for the development o f Reactive Airway Dys function Syndrome (RADS), a chemicallyor

irritant-induced type of asthma. About 2 to 4 weeks after an ingestion, consider follow-up esophagoscopy and an uppe r gas trointestinal tract series to evaluate secondary scarring o r stricture formation.
Patients who have skin or corneal injury should be re-examined within 24 hours. 

### Reporting If a w ork-related incident has occurred, you may be legall y requi red to file a report; contact your state or local healt h department.
Other per sons may still be at risk in the setting where thi s incide ntoccurred. If the incident occurred in the workplace , discus sing it with company personnel may prevent futur e incidents. I f a public health risk exists, notify your state or local health department or other responsible public agency. Whe n appropriate, inform pa tients that they may request an evaluation of their workplace from OSHA or NIOSH. See Appendices III and IV for a list of agencies that may be of assistance.

ATSDR • Emergency Department Management 17Hydrogen Chloride

18 Emergency Department Management • ATSDRHydrogen Chloride 

### Hydrogen Chloride Patient Information Sheet This handout provides information and follow-up instructions for persons who have been exposed to hydrogen chloride gas or hydrochloric acid solution. What are hydrogen chloride and hydrochloric acid? Hydr ogen chloride is a colorless to slightly yellow gas with a sharp, irritating odor. It forms a dens e white vapor wh en it comes in contact with air. When hydrogen chloride dissolves in water, it form s hydrochloric acid also known as muriatic acid. Both hydrogen chloride and hydrochloric acid ar e corrosive and may cause burns on contact. Hydrogen chloride is not flammable. What immediate health effects can be caused by exposure to these chemicals? Hydrogen chloride gas can irritate the lungs, causing a cough and shortness of breath. Breathing high levels of the gas o r vapor can lead to a build-up of fluid in the lungs, which may cause death. Because hydroch loric acid is corrosive, it can cause eye damage, even blindness, if splashed in the eyes. Ski n contact can cause severe burn s. Ingestion of concentrated hydrochloric acid can cause severe injury to the mouth, throat, esopha gus and stomach. Generally, the more serious the exposure, the more severe the symptoms. Can hydrogen chloride or hydrochloric acid overexposure be treated? There is no antidote for poisoning due to these substances, but their effects can be treated and mos t exposed persons get well. People who have had serious exposures may need to be hospitalized. Are any future health effects likely to occur? A single, small exposure from which a person recovers quickly is not likely to cause delayed or longterm effec ts. Patients who breath a large amount of hydrogen chloride may develop permanent lun g injury. If hydrochloric acid was swallowed, a patient may permanently have trouble swallowing. What tests can be done if a person has been exposed to hydrogen chloride? Specific test s for the presence of hydrogen chloride in blood or urine generally are not useful to th e doctor. If a severe exposure h as occurred, blood and urine analyses and other tests may show whether the lungs or stomach has been injured. Testing is not needed in every case. Where can more information about hydrogen chloride and hydrochloric acid be found? Mor e information about hydrogen chloride and hydrochloric acid can be obtained from your regional poison control center; your state, coun ty, or local health department; the Agency for Toxic Substances and Disease Registry (ATSDR); your doctor; or a clinic in your area tha t specializes in occupational and environmental health. If the exposure happened at work, you may wish to d iscuss it with your employer, the Occupational Safety and Health Administrati on (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.

ATSDR • Patient Information Sheet 19Hydrogen Chloride 

### Follow-up Instructions Keep this page and take it with you to your next appointment. Follow only the instructions checked below. [ ] Call y our doctor or the Emergency Department if you develop any unusual signs or symptoms within the next 24 hours, especially: C coughing or wheezing C difficulty breathing, shortness of breath, or chest pain C stomach pain or vomiting C increased pain or a discharge from exposed eyes

C increased redness or pain or a pus-like discharge in the area of a skin burn [ ] No follow-up appointment is necessary unless you develop any of the symptoms listed above. [ ] Call for an appointment with Dr. in the practice of

. When you call for your appointment, please say 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 1 to 2 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; smoke may worsen the condition of your lungs. [ ] Avoid drinking alcoholic beverages for at least 24 hours; alcohol may worsen injury to your stomach or have other effects. [ ] Avoid taking the following medications: [ ] You may continue taking the following medication(s) that your doctor(s) prescribed for you:

[ ] Other instructions:

• Provide the Emerg ency Department with the name and the number of your primary care physician so that the ED can send him or her a record of your emergency department visit.

• You or your physician can get more information on the chemical by contacting: or , or by checking out the following Internet Web sites: ; . Signature of patient Date Signature of physician Date

20 Patient Information Sheet • ATSDR