Nitric Acid

H272: May intensify fire; oxidizer [Danger Oxidizing liquids; Oxidizing solids]

H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

H330: Fatal if inhaled [Danger Acute toxicity, inhalation]

P210, P220, P260, P264, P271, P280, P284, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P320, P321, P363, P370+P378, P403+P233, P405, and P501 (click each P-code to see the statement)

H331: Toxic if inhaled [Danger Acute toxicity, inhalation]

P210, P220, P260, P261, P264, P271, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P321, P363, P370+P378, P403+P233, P405, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for < 0.1% (1 of 4215) of reports.

H272 (98.6%): May intensify fire; oxidizer [Danger Oxidizing liquids; Oxidizing solids]

H290 (18.9%): May be corrosive to metals [Warning Corrosive to Metals]

H314 (> 99.9%): Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

H318 (17.5%): Causes serious eye damage [Danger Serious eye damage/eye irritation]

H331 (11.9%): Toxic if inhaled [Danger Acute toxicity, inhalation]

P210, P220, P234, P260, P261, P264, P264+P265, P271, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P321, P363, P370+P378, P390, P403+P233, P405, P406, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 4215 reports by companies from 71 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 1 of 4215 reports by companies.

There are 70 notifications provided by 4214 of 4215 reports by companies with hazard statement code(s).

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

H290 (100%): May be corrosive to metals [Warning Corrosive to Metals]

H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]

P234, P264, P270, P301+P317, P330, P390, P406, and P501 (click each P-code to see the statement)

The GHS information provided by 1 company from 1 notification to the ECHA C&L Inventory.

H290: May be corrosive to metals [Warning Corrosive to Metals]

H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]

H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure]

H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

H402: Harmful to aquatic life [Hazardous to the aquatic environment, acute hazard]

P210, P220, P234, P260, P264, P264+P265, P270, P271, P273, P280, P284, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P308+P316, P316, P317, P319, P320, P321, P363, P370+P378, P390, P403+P233, P405, P406, and P501 (click each P-code to see the statement)

H304: May be fatal if swallowed and enters airways [Danger Aspiration hazard]

P210, P220, P260, P264, P264+P265, P270, P271, P280, P284, P301+P316, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P308+P316, P316, P317, P319, P320, P321, P331, P363, P370+P378, P403+P233, P405, and P501 (click each P-code to see the statement)

P210, P220, P260, P264, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P321, P363, P370+P378, P405, and P501 (click each P-code to see the statement)

Fresh air, rest. Half-upright position. Artificial respiration may be needed. Refer immediately for medical attention.

Wear protective gloves when administering first aid. First rinse with plenty of water for at least 15 minutes, then remove contaminated clothes and rinse again. Refer immediately for medical attention .

Rinse with plenty of water for several minutes (remove contact lenses if easily possible). Refer immediately for medical attention.

Rinse mouth. Give nothing to drink. Do NOT induce vomiting. Refer immediately for medical attention.

Excerpt from NIOSH Pocket Guide for Nitric acid:

Eye: IRRIGATE IMMEDIATELY - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: WATER FLUSH IMMEDIATELY - If this chemical contacts the skin, immediately flush the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water. Get medical attention promptly.

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Swallow: MEDICAL ATTENTION IMMEDIATELY - If this chemical has been swallowed, get medical attention immediately. (NIOSH, 2024)

General First Aid:

· Call 911 or emergency medical service.

· Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.

· Move victim to fresh air if it can be done safely.

· Administer oxygen if breathing is difficult.

· If victim is not breathing:

-- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.

-- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).

-- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.

· Remove and isolate contaminated clothing and shoes.

· For minor skin contact, avoid spreading material on unaffected skin.

· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.

· For severe burns, immediate medical attention is required.

· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

· Keep victim calm and warm.

· Keep victim under observation.

· For further assistance, contact your local Poison Control Center.

· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.

Specific First Aid:

· For corrosives, in case of contact, immediately flush skin or eyes with running water for at least 30 minutes. Additional flushing may be required.

· In case of skin contact with Hydrofluoric acid (UN1790), if calcium gluconate gel is available, rinse 5 minutes, then apply gel. Otherwise, continue rinsing until medical treatment is available.

In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product. Please consult the shipping paper and/or the "ERAP" section.

(General first aid procedures)

Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: Water flush immediately - If this chemical contacts the skin, immediately flush the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water. Get medical attention promptly.

Breathing: Respiratory support

Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.

Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

Note: Some foams will react with the material and release corrosive/toxic gases.

SMALL FIRE: CO2 (except for Cyanides), dry chemical, dry sand, alcohol-resistant foam.

LARGE FIRE: Water spray, fog or alcohol-resistant foam. If it can be done safely, move undamaged containers away from the area around the fire. Avoid aiming straight or solid streams directly onto the product. Dike runoff from fire control for later disposal.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. (ERG, 2024)

Use water in large amounts, carbon dioxide. NO powder, foam. In case of fire: keep drums, etc., cool by spraying with water. NO direct contact of the substance with water.

Approach fire from upwind to avoid hazardous vapors & toxic decomposition products. Use flooding quantities of water as spray or fog. Use water spray to keep fire-exposed containers cool. Extinguish fire using agent suitable for surrounding fire.

If material /is/ involved in /a/ fire, extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible.

If material /is/ involved in /a/ fire, use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. /Nitric acid, red, fuming/

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· Keep unauthorized personnel away.

· Stay upwind, uphill and/or upstream.

· Ventilate closed spaces before entering, but only if properly trained and equipped.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

· All equipment used when handling the product must be grounded.

· Do not touch damaged containers or spilled material unless wearing appropriate protective clothing.

· Stop leak if you can do it without risk.

· A vapor-suppressing foam may be used to reduce vapors.

· DO NOT GET WATER INSIDE CONTAINERS.

· Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material.

· Prevent entry into waterways, sewers, basements or confined areas.

Small Spill

· Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain.

· Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal.

Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)

SPILL: See ERG Table 1 - Initial Isolation and Protective Action Distances on the UN/NA 2032 datasheet.

Immediate precautionary measure

· Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

· For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.

· For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind direction, as necessary.

· If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.

Small spill:

- ISOLATE in all directions: 30 m (100 ft)

Large spill:

- ISOLATE in all directions: 150 m (500 ft)

- PROTECT people from downwind during DAY time: 0.1 km (0.1 mi)

- PROTECT people from downwind during NIGHT time: 0.1 km (0.1 mi)

- PROTECT people from downwind during DAY time: 0.3 km (0.2 mi)

- PROTECT people from downwind during NIGHT time: 0.5 km (0.3 mi)

Evacuate danger area! Consult an expert! Personal protection: chemical protection suit including self-contained breathing apparatus. Do NOT absorb in saw-dust or other combustible absorbents. Ventilation. Collect leaking liquid in sealable containers. Cautiously neutralize remainder with sodium carbonate. Then wash away with plenty of water.

Spilled nitric acid must not be absorbed with sawdust or other flammable material (because of the fire hazard); instead, its spread must be prevented by the construction of earth barriers.

1. Ventilate area of spill or leak. 2. Flush with copious quantities of water & neutralize with alkaline material (such as soda ash, lime, etc).

Environmental considerations: Air spill: Apply water spray or mist to knock down vapors. Vapor knockdown water is corrosive or toxic and should be diked for containment.

Environmental considerations: Land spill: Dig a pit, pond, lagoon, or holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash or cement powder. Neutralize with agricultural lime (CaO), crushed limestone, or sodium bicarbonate.

Environmental considerations: Water spill: Neutralize with agricultural lime (slaked lime), crushed limestone, or sodium bicarbonate. Air spill: Apply water spray or mist to knock down vapors. Vapor knockdown water is corrosive or toxic and should be diked for containment.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. A vapor-suppressing foam may be used to reduce vapors. DO NOT GET WATER INSIDE CONTAINERS. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Prevent entry into waterways, sewers, basements or confined areas.

SMALL SPILL: Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain. Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal. (ERG, 2024)

Separated from combustible substances, reducing agents, bases, organic chemicals and food and feedstuffs. Cool. Dry. Keep in a well-ventilated room. Store only in original container.

As a rule, nitric acid is stored in stainless steel tanks and transported in stainless steel containers.

Store in a cool, dry, well-ventilated location. Separate from alkalies, metals, organics, and other oxidizing materials.

Storage areas should be separated from other premises, well-ventilated, sheltered from sunlight and sources of heat ... should have a cement floor ... contain no substances with which ... acid might react. Large stocks ... surrounded by curbs or sills ... In the event of leakage & provisions for neutralization should be made. A fire hydrant ... should be ... outside ... storage premises. ... Electrical equipment should be of the water-proof type and resistant to acid attack. Safety lighting is desirable.

· Wear positive pressure self-contained breathing apparatus (SCBA).

· Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE.

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

TIH (Toxic Inhalation Hazard) - Term used to describe gases and volatile liquids that are toxic when inhaled. Some are TIH materials themselves, e.g., chlorine, and some release TIH gases when spilled in water, e.g., chlorosilanes. [ERG 2016].

AEGL 1: Notable discomfort, irritation, or certain asymptomatic non-sensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure (Unit: ppm)

AEGL 2: Irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape (Unit: ppm)

AEGL 3: Life-threatening health effects or death (Unit: ppm)

AEGLs Status: Final

0.16 [ppm]

24 [ppm]

92 [ppm]

2 ppm (5 mg/m³)

4 ppm (10 mg/m³)

TWA 2 ppm (5 mg/m3) ST 4 ppm (10 mg/m3)

2.0 [ppm]

TWA 2 ppm (5 mg/m3) See Appendix G

25 ppm (NIOSH, 2024)

25.0 [ppm]

Excerpts from Documentation for IDLHs: Other animal data: Rats receiving a single exposure to 63 mg/m3 nitric acid (24 ppm) exhibited no apparent adverse effects [Diggle and Gage 1954].

See: 7697372

4.0 [ppm]

8 hr Time Weighted Avg (TWA): 2 ppm; 15 min Short Term Exposure Limit (STEL): 4 ppm.

2 ppm as TWA; 4 ppm as STEL.

2 ppm [1992]

4 ppm [1992]

2.6 mg/m

· Note: Some foams will react with the material and release corrosive/toxic gases.

Small Fire

· CO2 (except for Cyanides), dry chemical, dry sand, alcohol-resistant foam.

Large Fire

· Water spray, fog or alcohol-resistant foam.

· If it can be done safely, move undamaged containers away from the area around the fire.

· Avoid aiming straight or solid streams directly onto the product.

· Dike runoff from fire control for later disposal.

Fire Involving Tanks, Rail Tank Cars or Highway Tanks

· Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.

· Do not get water inside containers.

· Cool containers with flooding quantities of water until well after fire is out.

· Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.

· ALWAYS stay away from tanks in direct contact with flames.

Nitric acid, other than red fuming appears as a pale yellow to reddish brown liquid with reddish brown vapors and a suffocating odor. Very toxic by inhalation. Corrosive to metals or tissue. Accelerates the burning of combustible material and may cause ignition of combustible materials upon contact. Prolonged exposure to low concentrations or short term exposure to high concentrations may result in adverse health effects. Density 12 lb / gal.

Nitric acid, red fuming appears as a pale yellow to reddish brown liquid generating red-brown fumes and having a suffocating odor. Very toxic by inhalation. Corrosive to metals or tissue. Prolonged exposure to low concentrations or short term exposure to high concentrations may result in adverse health effects. Rate of onset: Immediate Persistence: Hours - days Odor threshold: ~1 ppm Source/use/other hazard: Used in many industries; Very corrosive to skin/mucous membranes as well as metals & other materials.

CBI; Liquid; Other Solid; Liquid

Colorless, yellow, or red, fuming liquid with an acrid, suffocating odor. [Note: Often used in an aqueous solution. Fuming nitric acid is concentrated nitric acid that contains dissolved nitrogen dioxide.]; [NIOSH]

COLOURLESS-TO-YELLOW LIQUID WITH PUNGENT ODOUR.

Colorless, yellow, or red, fuming liquid with an acrid, suffocating odor.

Colorless, yellow, or red, fuming liquid with an acrid, suffocating odor. [Note: Often used in an aqueous solution. Fuming nitric acid is concentrated nitric acid that contains dissolved nitrogen dioxide.]

Transparent, colorless, or yellowish, fuming, hygroscopic, corrosive liquid

Colorless, yellow, or red fuming liquid.

Concentrated nitric acid is a colorless to yellow liquid.

Forms white, monoclinic crystals

Characteristic choking odor

Acrid; Sweet to acrid

Acrid, suffocating odor

1.1X10+3 N detection level in water. /Purity not specified/

181 °F at 760 mmHg (NIOSH, 2024)

83 °C @760 [mm Hg]

-44 °F (NIOSH, 2024)

-41.6 °C

The freezing point curve for aqueous solutions of nitric acid has two maxima corresponding to melting points for the two hydrates of nitric acid: the monohydrate (77.77 wt% acid) at -37.62 °C and the trihydrate (58.83 wt% acid) at -18.47 °C. Local minima occur at 32, 71, and 91 wt % acid.

Miscible (NIOSH, 2024)

Very soluble in water

Miscible with water

Solubility in water at 20 °C: miscible

Miscible

1.5 at 77 °F (NIOSH, 2024) - Denser than water; will sink

1.5129 g/cu cm at 20 °C

Fuming nitric acid is concentrated nitric acid that contains dissolved nitrogen dioxide. The density and vapor pressure of such solutions increase with the percentage of nitrogen dioxide present.

Relative density (water = 1): 1.4

1.5129 @ 20°C

(77 °F): 1.50

Relative vapor density (air = 1): 2.2

48 mmHg (NIOSH, 2024)

63.1 [mmHg]

63.1 mm Hg at 25 °C

Vapor pressure, kPa at 20 °C: 6.4

75 [mm Hg] @28.4 °C

On exposure to atmospheric humidity or heat there is decomposition with the formation of nitrogen peroxide.

When heated to decomposition it emits highly toxic fumes of /nitrogen oxide/ and hydrogen nitrate.

Nitric acid is unstable, decomposing on contact with heat and exposure to light, water, nitrogen dioxide, and oxygen.

Fumes in air. Fully soluble in water with the release of heat. Reacts violently with water with the production of heat, fumes, and spattering.

Fumes in air. Soluble in all proportions with water. Dissolution in water produces heat, fumes, and spattering.

Acids, Strong Oxidizing

Strong Oxidizing Agent

Known Catalytic Activity

Water-Reactive

CSL00004

Acetic anhydride + NITRIC ACID

Can explode and/or have large exotherm. Use only 1 eq. HNO3 and in high dilution.

Explosive

Nitration

User-Reported

CSL00008

NITRIC ACID + TERT-BUTYL CARBAZATE

Explosion during workup when half of the solvent was evaporated

BOCN3 formation

CSL00055

ACETONE + NITRIC ACID

Potentially explosive

CSL00067

Acetic anhydride + ACETIC ACID + NITRIC ACID

CSL00068

METHANOL + NITRIC ACID

Potentially explosive in the presence of polar molecules

CSL00110

NITRIC ACID + ACETONITRILE

Mixtures of fuming nitric acid and acetonitrile are high explosives.

Note that acetonitrile is one of many chemicals that can form explosive mixtures with fuming nitric acid

Bretherick's

CSL00155

Sodium hypochlorite + Nitric acid

The reaction produced chlorine gas and potentially fluorine gas which are extremely hazardous.

Gas Emitter

Not Available

Substance identification sources: Sodium hypochlorite. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=7681-52-9 (retrieved 2022-01-27) (CAS RN: 7681-52-9). Nitric acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=7697-37-2 (retrieved 2022-01-27) (CAS RN: 7697-37-2).

User Reported

01/27/2022

NITRIC ACID ignites upon contact with alcohols, amines, ammonia, beryllium alkyls, boranes, dicyanogen, hydrazines, hydrocarbons, hydrogen, nitroalkanes, powdered metals, silanes, or thiols [Bretherick 1979. p.174]. The reaction of finely divided antimony and nitric acid can be violent [Pascal 10:504. 1931-34]. Bromine pentafluoride reacts violently with strong nitric acid and strong sulfuric acid [Mellor 2, Supp. 1:172. 1956]. Fuming nitric acid reacts with hydrogen selenide with incandescence [Berichte 3:658]. Fuming nitric acid reacts with hydrogen sulfide with incandescence [Berichte 3:658]. A mixture of finely divided magnesium and nitric acid is explosive [Pieters 1957. p. 28]. Nitric acid oxidizes magnesium phosphide with incandescence [Mellor 8:842. 1946-47]. Experiments show that mixtures of over 50% nitric acid by weight in acetic anhydride may act as detonating explosives [BCISC 42:2. 1971]. An etching agent of equal portions of acetone, nitric acid, and 75% acetic acid exploded four hours after it was prepared and placed in a closed bottle. This is similar to a formulation for the preparation of tetranitromethane a sensitive explosive [Chem. Eng. News 38: 56. 1960]. Phosphine is violently decomposed by concentrated nitric acid, and flame is produced. Warm fuming nitric acid, dropped in a container of phosphine gas produces an explosion [Edin. Roy. Soc. 13:88. 1835]. An explosion occurs when nitric acid is brought into contact with phosphorus trichloride [Comp. Rend. 28:86]. The exothermic nitration of phthalic acid or phthalic anhydride by fuming nitric acid-sulfuric acid may give mixtures of the potentially explosive phthaloyl nitrates or nitrites or their nitro derivatives [Chem. & Ind. 20:790. 1972]. The reaction of sodium azide and strong nitric acid is energetic [Mellor 8, Supp 2:315. 1967]. Nitric acid can react with uranium with explosive violence [Katz and Rabinowitch 1951]. Reacts violently with water with the production of heat, fumes, and spattering.

NITRIC ACID, RED FUMING is a powerful oxidizing agent and nitrating agent. Accelerates the burning of combustible material and may cause charring and then ignition of combustible materials. May ignite alcohols, amines, ammonia, beryllium alkyls, boranes, dicyanogen, hydrazines, hydrocarbons, hydrogen, nitroalkanes, powdered metals, silanes, or thiols on contact [Bretherick 1979. p.174]. Can react violently with finely divided antimony [Pascal 10:504. 1931-34]. Reacts violently with bromine pentafluoride [Mellor 2, Supp. 1:172. 1956]. Reacts with hydrogen selenide and hydrogen sulfide with incandescence [Berichte 3:658]. Mixtures with finely divided magnesium are explosive [Pieters 1957 p. 28]. Oxidizes magnesium phosphide with incandescence [Mellor 8:842. 1946-47]. Mixtures with acetic anhydride containing over 50% nitric acid by mass may act as detonating explosives [BCISC 42:2. 1971]. An etching agent prepared with equal portions of acetone, nitric acid, and 75% aqueous acetic acid exploded four hours after it was prepared and placed in a closed bottle. The explosive material may have been tetranitromethane [Chem. Eng. News 38: 56. 1960]. Reacts violently with phosphine [Edin. Roy. Soc. 13:88. 1835]. Explodes in contact with phosphorus trichloride [Comp. Rend. 28:86]. Reacts exothermically with phthalic acid or phthalic anhydride in the presence of sulfuric acid to give potentially explosive phthaloyl nitrates or nitrites or nitro derivatives of these compounds [Chem. & Ind. 20:790. 1972]. Reacts energetically with sodium azide [Mellor 8, Supp 2:315. 1967]. Reacts with uranium with explosive violence [Katz and Rabinowitch 1951].

Reacts violently with combustible or readily oxidizable materials such as alcohols, turpentine, charcoal, organic refuse. Reacts with most metals to release hydrogen gas.

Nitric acid is a corrosive acid and a powerful oxidizing agent. The major hazard posed by it is chemical burns as it carries out acid hydrolysis with proteins (amide) and fats (ester) which consequently decomposes living tissue (e.g. skin and flesh). Concentrated nitric acid stains human skin yellow due to its reaction with the keratin. These yellow stains turn orange when neutralized. Systemic effects are unlikely, however, and the substance is not considered a carcinogen or mutagen.

Ingested nitrate or nitrite under conditions that result in endogenous nitrosation is probably carcinogenic to humans (Group 2A). (L135)

Skin contact with nitric acid can cause redness, pain, and severe skin burns. Nitric acid may cause severe burns to the eye and permanent eye damage. Severe and rapid corrosive burns of the mouth, gullet and gastrointestinal tract will result if nitric acid is swallowed. Symptoms include burning, choking, nausea, vomiting and severe pain.

Serious local effects by all routes of exposure.

inhalation, ingestion, skin and/or eye contact

Oral (L1137) ; inhalation (L1137)

Cough. Sore throat. Burning sensation. Shortness of breath. Laboured breathing.

Pain. Yellow staining of the skin. Serious skin burns.

Redness. Pain. Severe burns.

Burns in mouth and throat. Burning sensation behind the breastbone. Abdominal pain. Vomiting. Shock or collapse.

irritation eyes, skin, mucous membrane; delayed pulmonary edema, pneumonitis, bronchitis; dental erosion

Skin contact can cause redness, pain, and severe skin burns. Nitric acid may cause severe burns to the eye and permanent eye damage. Severe and rapid corrosive burns of the mouth, gullet and gastrointestinal tract will result if nitric acid is swallowed. Symptoms include burning, choking, nausea, vomiting and severe pain.

Eyes, skin, respiratory system, teeth

Dermatotoxin - Skin burns.

Toxic Pneumonitis - Inflammation of the lungs induced by inhalation of metal fumes or toxic gases and vapors.

ACGIH Carcinogen - Not Classifiable.

LC50 (rat) = 67 ppm (NO2)/4H

LD50: 138 ppm over 30 minutes (Inhalation, Rat) (A677)

LC50 Sheep inhalation 0.004 mg/L 4 hr

LC50 Rat inhalation 7 mg/L 1hr

LC50 Mouse inhalation 67 ppm/4hr /Nitric acid, red fuming/

LC50 Rat inhalation 334 ppm/30 min

For more Non-Human Toxicity Values (Complete) data for NITRIC ACID (8 total), please visit the HSDB record page.

The mainstay of treatment of any acid burn is copious irrigation with large amounts of tap water. To be most effective, treatment should be started immediately after exposure, preferably before arrival in the emergency department. Remove any contaminated clothing. Do not attempt to neutralize the burn with weak reciprocal chemicals (i.e. alkali for acid burns), because the heat generated from the chemical reaction may cause severe thermal injury.

Respiratory tract injury resulting from inhalation of mixtures of ozone and nitrogen dioxide and of ozone and formaldehyde was studied in Sprague-Dawley rats under exposure conditions of rest and exercise. Mixtures of ozone (0.35 or 0.6 ppm) with nitrogen dioxide (respectively 0.6 or 2.5 ppm) doubled the level of lung injury produced by ozone alone in resting exposures to the higher concn and in exercising exposures to the lower concn. Mixtures of ozone and nitrogen dioxide at high and low concn formed respectively 0.73 and 0.02 ppm nitric acid (HNO3) vapor. Chemical interactions among the oxidants, HNO3, and other reaction products (nitrogen pentoxide and nitrate radical) and lung tissue may be the basis for the ozone-nitrogen dioxide synergism. Increased dose and dose rate associated with exercise exposure may explain the presence of synergistic interaction at lower concn than observed in resting exposure. No oxidation products were detected in ozone-formaldehyde mixtures, and the antagonistic interaction observed in lung tissue during resting exposure may result from irritant breathing pattern interactions.

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Inorganic acids and related compounds/

Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist respirations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. Activated charcoal is not effective. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Do not attempt to neutralize because of exothermic reaction. Cover skin burns with dry, sterile dressings after decontamination ... . /Inorganic acids and related compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Early intubation, at the first sign of upper airway obstruction, may be necessary. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's(LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Inorganic acids and related compounds/

A complete history and physical exam: The purpose is to detect existing conditions that might place the exposed employee at incr risk, and to establish a baseline for future health monitoring. Examination of the eyes, respiratory tract, skin, and teeth should be stressed. The skin should be examined for evidence of chronic disorders.

NIOSH recommends that workers subject to nitric acid exposure have comprehensive preplacement and annual medical examinations including a 14"X17" posterior-anterior chest x-ray, pulmonary function tests, and a visual examination of the teeth for evidence of dental erosion.

Respiratory Symptom Questionnaires: Questionnaires have been published by the American Thoracic Society and the British Medical Research Council. These questionnaires have been found to be useful in identification of people with chronic bronchitis, however certain pulmonary function tests such as FEV 1 have been found to be better predictors of chronic airflow obstruction.

Chest Radiography: This test is widely used for assessing pulmonary disease. Chest radiographs have been found to be useful for detection of early lung cancer in asymptomatic people, especially for detection of peripheral tumors such as adenocarcinomas. However, even though OSHA mandates this test for exposure to some toxicants such as asbestos, there are conflicting views on its efficacy in detection of pulmonary disease.

For more Medical Surveillance (Complete) data for NITRIC ACID (6 total), please visit the HSDB record page.

/HUMAN EXPOSURE STUDIES/ The use of a 0.2-ppm NOEL for healthy humans exposed to HNO3 based on /a previous/ study appears appropriate. However, /subsequent/ studies indicate that individuals with asthma might be more sensitive than those without. In these studies, adolescent asthmatic subjects (six males and nine females) with exercise-induced bronchospasm were exposed via a rubber mouthpiece with nose clips to HNO3 aerosol at a concentration of 0.05 ppm (130 ug/cu m). Respiratory function was measured at the end of the exposure. The exposure at 0.05 ppm for 40 min (30 min at rest followed by a 10-min moderate exercise period) produced a decrease in forced expiratory volume (FEV) of 4% and an increase in respiratory resistance of 23%. The authors concluded that individuals with asthma represent a population group that might be exquisitely more sensitive to the effects of HNO3 than healthy individuals.

/HUMAN EXPOSURE STUDIES/ /Investigators/ showed that a 200-ug/cu m (0.08 ppm) exposure for 2 hr produced no adverse respiratory effects in nine human subjects. That concentration was chosen to represent a concentration of HNO3 that was higher than those observed in ambient air (EPA 1993); ambient concentrations ranged from 0.1 to 20 ppb. Later, /the same investigators/ used the same exposure concentration and duration, but did not observe any adverse effects as judged by bronchoalveolar lavage and pulmonary-function tests. None of the biochemical measures, such as protein levels, lactate dehydrogenase (LDH), and fibronectin, changed as a result of the exposure. The investigators observed a surprising increase in the phagocytic activity of alveolar macrophages from exposed individuals, but that was not believed to be an adverse effect. Therefore, no toxic effects occurred in humans exposed to HNO3 for 2 hr at 0.08 ppm.

/HUMAN EXPOSURE STUDIES/ /Investigators/ conducted a ... study to determine the effects of HNO3 gas, not aerosol, in healthy humans. They designed the study to reflect the conditions of exposure that might occur in dry weather. The test subjects (eight males and two females) were exposed to HNO3 at 500 ug/cu m (0.2 ppm) in a 2.5 x 2.5 x 2.4 meter chamber for 4 hr during moderate exercise. Eighteen hours later the subjects underwent bronchoscopy, which included bronchial lavage and bronchial biopsy to evaluate biochemical and morphological changes. The study was done carefully and a number of end points were examined, including pulmonary function. None of the assessments of respiratory toxicity showed any effects from HNO3 gas in the 10 subjects. Therefore, a human no-observed-effect level (NOEL) for HNO3 can be established as 0.2 ppm for 4 hr.

/HUMAN EXPOSURE STUDIES/ In a study with humans, exposure of 12 nonsmoking subjects with mild asthma for 3 min to an "acid fog" that was 30 milliosmolar (mOsm) at pH 2 significantly increased specific airway resistance. The approximate concentration of HNO3 in those studies was very high, 40 mg/cu m (15 ppm). Subjects inhaled the aerosols through a mouthpiece from an ultrasonic nebulizer. Bronchoconstriction was correlated with acidity of the fog, not the nature of the acid, since fogs made up of either HNO3 or H2SO4 or both showed equally potent effects. These studies showed that very short exposures to high concentrations of HNO3 can cause moderate-to-severe effects in sensitive humans.

For more Human Toxicity Excerpts (Complete) data for NITRIC ACID (20 total), please visit the HSDB record page.

/LABORATORY ANIMALS: Acute Exposure/ ... A single exposure to nitric acid mist in a concentration of 63 mg/cu m had no apparent adverse effect on rats.

/LABORATORY ANIMALS: Acute Exposure/ Based on acute parallel exposures of rats to white (97.5%) nitric acid vapor, nitrogen dioxide, or nitrogen dioxide (8%-17% dissolved) in red fuming nitric acid. ... /Investigators/ concluded nitrogen dioxide was the primary toxic constituent of fuming nitric acid and that nitric acid may potentiate the toxicity of inhaled nitrogen dioxide. Nitric acid vapor alone was less toxic to rats on inhalation than was an equivalent exposure to nitrogen dioxide or the red fuming preparation of nitric acid.

LC50; Species: Carcinus maenas (Shore crab); Conditions: /static, aerated water/; Concentration: 180 mg/L for 48 hr

LC50; Species: Cerastoderma edule (Cockle); Conditions: renewal, /aerated water/; Concentration: 330-1000 mg/L for 48 hr

LC50; Species: Asterias rubens (Starfish); Conditions: renewal, /aerated water/; Concentration: 100-300 mg/L for 48 hr

LC50; Species: Agonus cataphractus (Hooknose or pogge); Conditions: saltwater, renewal; Concentration: 100-330 mg/L for 48 hr

/AQUATIC SPECIES/ /A/ semi-static open-system 96 hr acute toxicity test using the freshwater fish Aphanius dispar /was conducted/. After acclimation, 15 fish were transferred to each test aquarium at pH 4.5, 4.0, 3.75, 3.25, or 3.0. The control had a pH of 7.6. The pH grades were prepared by adding the required amount of the respective acids. The number of dead fish at each pH was registered at 6, 24, 48, 72, and 96-hours of exposure. ...Initially, exposure to the lethal pH resulted in hyperactivity, erratic swimming, and occasional convulsion. Over time, fish at pH 4.5 and 4.0 settled motionless at the bottom and those at pH 3.25 and 3.0 showed restlessness. Test animals secreted mucus so profusely at advanced stages of exposure that the water became milky. At the final stage of exposure, fish lost their sense of balance and swam lateral-side up. Physiological and mechanical responses eventually resulted in death in some specimens. The results of this study show that nitric acid is only moderately toxic while sulfuric acid is the most toxic. Therefore, the quantity as well as quality of acid must be considered in assessing the impact of acid precipitation in fish populations.

/AQUATIC SPECIES/ The concentration of hydrogen ions which caused 50% mortality of bluegill in 96 hr was between pH 3.5 and 3.0 for nitric acid. The quantity rather than the quality of acids is the primary factor in fish toxicity brought about by acid parts per thousand. At sublethal concentrations of acid, bluegill became hypoactive with respect to their swimming behavior.

/AQUATIC SPECIES/ The acute toxicity of nitric acid to fingerling rainbow trout was measured in a 7 day bioassay at 11 °C. The medium lethal concentration was approx pH 4.0. Fish which died at low pH (3.0-4.0) exhibited classical symptoms of acid toxicity. Comparison of the present results with other toxicity measurements suggests that nitric acid has intermediate toxicity between sulfuric acid and hydrochloric acid at pH 3.0 and less toxic than either acid at pH greater than or equal to 3.3.

/AQUATIC SPECIES/ /A/ semi-static open-system 7 day toxicity test using the freshwater fish /Oncorhynchus mykiss/ (Rainbow trout, 0.95 g fish) /was conducted/. ...Tests were run in 38-L glass aquarium containing filtered tapwater adjusted to the treatment pH. The aquaria were held at 11 °C under a 12-hr light/12-hr dark cycle. Ten fish were randomly selected for each treatment and each treatment was randomly assigned to an incubator. The following treatments were used: pH 3.0, 3.3, 3.7, 4.0, 4.3, 4.7, and 5.0 tapwater, and tapwater plus nitric acid. The water was bubbled to remove CO2. Final adjustment to the experimental pH was done using reagent grade NaOH. ...At pH 3.0 to 4.0, fish became flecked with thick white mucus just prior to death and exhibited "coughing". They became disoriented shortly before death and tended to drift in the current produced by the aeration in the tank. Fish that died at pH 5.0 didn't show any of these symptoms. The authors were unable to explain the mortality observed at pH 5.0. Comparison with the results of this experiment and results of other toxicity studies suggests that HNO3 is intermediate in toxicity between H2SO4 and HCl at pH 3.0 and less toxic than either acid at pH 3.3 and above.

For more Ecotoxicity Excerpts (Complete) data for NITRIC ACID (6 total), please visit the HSDB record page.

Nitric acid is formed in the troposphere by gas-phase chemistry.

SRP: Component of acid rain.

TERRESTRIAL FATE: During transport through the soil, nitric acid will dissolve some of the soil material, in particular, the carbonate based materials. The acid will be neutralized to some degree with adsorption of the proton also occurring on clay materials. However, significant amounts of acid are expected to remain for transport down toward the ground water table. Upon reaching the ground water table, the acid will continue to move, now in the direction of the ground water flow. A contaminated plume will be produced with dilution and dispersion serving to reduce the acid concn.

ATMOSPHERIC FATE: In Colorado, nitric acid vapor is scavenged by incorporation into snow.

ATMOSPHERIC FATE: A mesoscale model of pollutant transport, transformation and deposition was used to perform a detailed analysis of acidic deposition to the states of New York and Ohio (USA) during a 3 day springtime deposition episode. This model can be used to assess the roles of wet and dry deposition to individual land types in the removal of pollutants from the atmosphere. Over two-thirds (67%, Ohio; 78%, New York) of the acidic deposition during this rainy period fell as wet deposition, primarily in the form of sulfuric acid. Dry deposition of sulfur dioxide accounted for 70-75% of the total dry acidic deposition in both areas, and most of the remaining dry deposition occurred as nitric acid. Over both deposition areas, particulate sulfate deposition accounted for < 1% of the total acid deposition. Due to the highly surface specific nature of the dry deposition process, individual land types displayed unique patterns of pollutant uptake. Water surfaces absorbed primarily sulfur dioxide, while rougher forested areas absorbed a larger proportion of nitric acid vapor. Urban areas, with their associated material surface, were found to absorb significantly less acid in the dry form, and during dry periods most of this deposition may occur as nitric acid vapor, although considerable uncertainty exists regarding the treatment of rainfall wetted surfaces. These model results suggest that dry pollutant fluxes to individual surface types will show significant variability from any averaged flux estimates over larger areas encompassing numerous land types.

ATMOSPHERIC FATE: Dry deposition of nitric acid (HNO3) to forests is controlled by aerodynamic properties of the canopy. Most surfaces are strong sinks for HNO3, and measurements show that deposition rates to vegetation are determined entirely by atmospheric transport, i.e. there are no surface resistances limiting uptake rates. For a typical forest 10 m high in a wind speed of about 5 m/sec, values of deposition velocity for HNO3 are likely to be in the range 50-100 mm/sec. For an avg air concn of HNO3 of 0.5 nL/L this would result in the deposition of about 4-8 kg N/ha/yr. A multi-layer canopy gas and radiation exchange model (Maestro) was modified to calculate air pollutant deposition. Leaf boundary layer resistances, and stomatal resistances in the model were adjusted for gas molecular diffusivity, and leaf surface resistances and internal resistances were added. A comparison between HNO3 deposition on Keilder Forest (300 m above sea level), United Kingdom and Whitetop Mountain (1682 m above sea level), Virginia for 6 mo (spring-summer) gave gas concn of 0.3 nL/L and 0.7 nL/L, respectively.

Nitric acid will be gradually neutralized by hardness minerals (calcium and magnesium) in water. The nitrate ion may persist longer but will ultimately be consumed as a plant nutrient.

Nitric acid is removed from the gas phase in the lower atmosphere at temperatures lower than 195 K through the formation of crystalline nitric acid trihydrate; below 188 K, nitric acid is found in association with ice crystals(1).

... Nitric acid ... reduced the amount of carbon mineralized ... in soil amended with 1% glucose ... than did hydrogen sulfate.

RAIN/SNOW: Rain chemistry was measured in August 1983 on Allegheny Mountain and Laurel Hill in southwestern Pennsylvania (USA). The average composition approximated an sulfuric acid/ nitric acid mixture with a volume-weighted average pH of 3.5 and sulfate/nitrate mole ratio of 1.8. There was very little undissociated (weak) acidity and very little sulfur(IV). The acidic rains were associated with air masses traversing sulfur dioxide source regions west of the sites; stagnation and intervening precipitation were important influences. The geographic scale for a halving of rain sulfate concentration downwind of sulfur dioxide sources washing ratios were inferred for sulfur dioxide, aerosol sulfate, and nitric acid. On average about half of the rain sulfate resulted from scavenging of sulfur dioxide, the rest from scavening of aerosol sulfate. The rain hydrogen was attributed about 25% to nitric acid, 55% to scavenging of sulfur dioxide, and 20% to scavenging of aerosol acid sulfate. Cumulative deposition totals in rain were compared with deposition in fog and with dry deposition in the same experiment. A crude acid deposition budget was calculated as follows: 47%, sulfuric acid in rain; 23%, sulfur dioxide dry deposition without dew; 16%, nitric acid and sulfuric acid in fog and dew; 0.5%, aerosol dry deposition without dew.

URBAN/SUBURBAN: The level of nitric acid outside of seven Southern California museums were 6.7 (El Pueblo), 4.0 (Olivas), 7.1 (LACMA), 13.0 (Huntington), 15 (Natural History), 5.5 (Page), 13 (UCLA), and 4.4 (Southwest) ppb(1).

RURAL/REMOTE: Nitric acid was detected in 6 hr average trace gas and aerosol samples at a mean concentration of 0.85 ppb during winter analysis of samples collected January 20 to February 24, 1989 from Powassan, a rural site in south central Ontario, Canada(1). Nitric acid was detected, not quantified at Lewes, Delaware and High Point Bermuda during air sampling conducted across the Western Atlantic Ocean from Delaware to Bermuda in March, 1985 (detection limit = 10 parts/trillion volume)(2). Measurements of airborne nitric acid in the area of the Azores, mid-North Atlantic Ocean resulted in a mean concentration of 0.13 ug/cu m under an anticyclonic event in June 1992. Samples from air which had crossed over the British Isles three days earlier showed a mean concentration of 0.17 ng/cu m(3). Long-range transport of nitric acid was illustrated at a coastal clean air station south of Gottenburg Sweden. Mean monthly nitric acid gas-phase concentrations were 30, 47, 110, 120, 120, 80, 50, 45, 46, 47, 90 and 47 nmol/cu m, as a result of measurements taken from November 1981 to October 1982. The corresponding particulate-phase concentrations were 23, 24, 61, 63, 90, 51, 24, 15, 25, 26, 75, and 27 nmol/cu m. Mean and maximum concentrations of nitric acid at Rorvik, Sweden were 32 and 140 nmole/cu m (November 1981 through April 1982), respectively, and 18 and 86 nmol/cu m (April 1982 through October 1982), respectively, exhibiting an overall mean of 25 nmole/cu m(4).

SOURCE DOMINATED: Nitric acid maximum concentrations were 4.5 ppb and 6.3 ppb from two southern California smog receptor sites; Perris and Palm Springs are located 90 and 120 km east-south east and east of Los Angeles, respectively. Sampling was conducted from June 1989 to June 1990, as part of the Southern California Air Quality Study. Seasonal concentrations were 1.4 (spring), 1.4 (summer), 0.8 (fall), and 0.4 (winter) ppb for Perris and 1.2 (spring), 0.6 (summer), 0.8 (fall), and 0.8 (winter) ppb for Palm Springs(1).

INDOOR: The level of nitric acid in seven Southern California museums were 7.6 (El Pueblo), 5.7 (Olivas), 10.4 (LACMA), 3.6 (Huntington), 3.7 (Natural History), 5.0 (Page), 9.7 (UCLA), and 3.7 (Southwest) ppb(1).

Nitric acid is present in the gas-phase of environmental cigarette smoke; the average concentration range was reported as 24 to 380 umol/mol CO, generated using one to four cigarette (1R1 Kentucky Reference cigarette) electrically lit and burned in a 30 cu cm Teflon chamber(1).

According to the 2006 TSCA Inventory Update Reporting data, the number of persons reasonably likely to be exposed in the industrial manufacturing, processing, and use of nitric acid is 1000 or greater; the data may be greatly underestimated(1).

ANILINE MANUFACTURE BY NITRATION OF BENZENE AND SUBSEQUENT REDUCTION OF THE NITROBENZENE INVOLVES POTENTIAL EXPOSURES TO NITRIC ACID, NITROGEN OXIDES, BENZENE, AND NITROBENZENE, IN ADDITION TO ANILINE ITSELF.

The following occupations are potentially exposed to nitric acid: Aircraft workers, ammonium nitrate makers, bleachers, brass cleaners, bright dip workers, cellulose nitrate makers, drug makers, dyemakers, electroplaters, etchers, jewelers, chemical laboratory workers, lithographers, mirror makers, nitration workers, nitric acid workers, nitrobenzene makers, nitro-compound workers, oreflotation workers, organic chemical synthesizers, photoengravers, rocket fuel handlers, steel etchers, and, sulfuric acid makers.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Disposal of waste nitric acid into sewers or watercourses should not be permitted until the ph of the soln is /SRP: adjusted/ to a range of 5.5-8.5.

Recovering: Sodium carbonate-calcium hydroxide is added to form the neutral soln of nitrate of sodium and calcium. This soln can be discharged after dilution with water. Also, nitric acid can be recovered and reused. Recommendable methods: Neutralization & discharge to sewer. Not recommendable method: Landfill. Peer-review: Prior to neutralization dilute 10 times. Beware - Potential toxic. (Peer-review conclusions of an IRPTC expert consultation (May 1985))

If ... THERE IS NO FIRE, go directly to the Table of Initial Isolation and Protective Action Distances /(see table below)/ ... to obtain initial isolation and protective action distances. IF THERE IS A FIRE, or IF A FIRE IS INVOLVED, go directly to the appropriate guide /(see guide(s) below)/ and use the evacuation information shown under PUBLIC SAFETY. /Nitric acid, fuming; Nitric acid, red fuming/

Table: Table of Initial Isolation and Protective Action Distances for Nitric acid, fuming; Nitric acid, red fuming [Table#3445]

/GUIDE 157: SUBSTANCES - TOXIC AND/OR CORROSIVE (NON-COMBUSTIBLE/WATER -SENSITIVE)/ Health: TOXIC; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance may cause severe injury, burns, or death. Reaction with water or moist air will release toxic, corrosive or flammable gases. Reaction with water may generate much heat which will increase the concentration of fumes in the air. Fire will produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution. /Nitric acid, fuming; Nitric acid, red fuming; Nitric acid, other than red fuming/

/GUIDE 157: SUBSTANCES - TOXIC AND/OR CORROSIVE (NON-COMBUSTIBLE/WATER -SENSITIVE)/ Fire or Explosion: Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Vapors may accumulate in confined areas (basement, tanks, hopper/tank cars etc.). Substance will react with water (some violently), releasing corrosive and/or toxic gases. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or contaminated with water. /Nitric acid, fuming; Nitric acid, red fuming; Nitric acid, other than red fuming/

/GUIDE 157: SUBSTANCES - TOXIC AND/OR CORROSIVE (NON-COMBUSTIBLE/WATER -SENSITIVE)/ Public Safety: CALL Emergency Response Telephone Number ... As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate enclosed areas. /Nitric acid, fuming; Nitric acid, red fuming; Nitric acid, other than red fuming/

For more DOT Emergency Guidelines (Complete) data for NITRIC ACID (9 total), please visit the HSDB record page.

2031 157(other than red fuming)

2032 157(fuming)

UN 2032; Nitric acid, red fuming

UN 2031; Nitric acid other than red fuming, with at least 65 percent, but not more than 70 percent nitric acid; Nitric acid other than red fuming, with more than 20 percent and less than 65 percent nitric acid; Nitric acid other than red fuming with not more than 20 percent nitric acid; Nitric acid other than red fuming, with more than 70 percent nitric acid

IMO 8.0; Nitric acid other than red fuming, with more than 70% nitric acid; Nitric acid other than red fuming, with not more than 70% nitric acid; Nitric acid, red fuming

49 185 25; Nitrating acid, mixture (with more than 50% nitric acid)

49 302 45; Nitrating acid, mixture (with not more than 50% nitric acid)

49 302 54; Nitrating acid, spent

49 185 28; Nitric acid (over 40%)

49 185 29; Nitric acid, fuming

49 302 42; Nitric acid, 40% or less

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

Corrosive Oxidizer

Corrosive Oxidizer Poison Inhalation Hazard

Unbreakable packaging. Put breakable packaging into closed unbreakable container. Do not transport with food and feedstuffs.

Symbol: O, C; R: 8-35; S: (1/2)-23-26-36-45; Note: B

UN Hazard Class: 8; UN Subsidiary Risks: 5.1; UN Pack Group: I