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Chemical Datasheet

HYDROGEN CYANIDE, SOLUTION IN ALCOHOL, WITH NOT MORE THAN 45% HYDROGEN CYANIDE

6.1 - Poison Inhalation Hazard 3 - Flammable liquid

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 74-90-8   (HYDROGEN CYANIDE)
  • 64-17-5   (ETHANOL)
  • 3294
  • Poison Inhalation Hazard
  • Flammable Liquid
none
NIOSH Pocket Guide International Chem Safety Card
Hydrogen cyanide
  • ETHANOL (ANHYDROUS)
  • HYDROGEN CYANIDE, LIQUEFIED
NFPA 704
Diamond Hazard Value Description
4
4 1
Blue Health 4 Can be lethal.
Red Flammability 4 Burns readily. Rapidly or completely vaporizes at atmospheric pressure and normal ambient temperature.
Yellow Instability 1 Normally stable but can become unstable at elevated temperatures and pressures.
White Special
Note: NFPA ratings shown are for hydrogen cyanide, CAS number 74-90-8
(NFPA, 2010)
General Description
A clear colorless liquid with a faint odor of bitter almonds. Less dense than water. Vapors are slightly lighter than air. Vapors are very toxic by inhalation or skin contact. Prolonged exposure to heat can cause a closed container to rupture violently and rocket.

Hazards

Reactivity Alerts
Air & Water Reactions
Highly flammable. Reacts with water to release gaseous hydrogen cyanide (very poisonous).
Fire Hazard
Excerpt from 131 Polymerizable warning [Flammable Liquids - Toxic]:

HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. CAUTION: Methanol (UN1230) will burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.) Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas (sewers, basements, tanks, etc.). Vapor explosion and poison hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids will float on water. (ERG, 2020)
Health Hazard
Excerpt from 131 Polymerizable warning [Flammable Liquids - Toxic]:

TOXIC; may be fatal if inhaled, ingested or absorbed through skin. Inhalation or contact with some of these materials will irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or asphyxiation. Runoff from fire control or dilution water may cause environmental contamination. (ERG, 2020)
Reactivity Profile
HYDROGEN CYANIDE, SOLUTION IN ALCOHOL, WITH NOT MORE THAN 45% HYDROGEN CYANIDE reacts with acid to evolve hydrogen cyanide, a very poisonous colorless gas smelling of bitter almonds. The solution also evolves gaseous hydrogen cyanide when heated. Inhalation of the gas is quickly fatal by respiratory arrest. The gas forms flammable or explosive mixtures with air (may be difficult to ignite at lower concentrations), presents an explosion hazard when heated with or exposed to other oxidizing agents, and may polymerize explosively at elevated temperature (50-60°C) or in the presence of traces of alkali [Wohler, L. et al., Chem. Ztg., 1926, 50, p. 761, 781]. Solution may react violently with acetaldehyde. Is incompatible with isocyanates, nitrides, peroxides, and epoxides. May react exothermically with metal salts. May generate flammable and/or toxic gases with alkali metals, nitrides, and strong reducing agents. During the preparation of imidoester hydrochlorides, hydrogen chloride was rapidly passed over an alcoholic solution of hydrogen cyanide. An explosion ensued, despite cooling of the process [J. Org. Chem., 1955, 20, 1573].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below.

Response Recommendations

Isolation and Evacuation
Excerpt from 131 Polymerizable warning [Flammable Liquids - Toxic]:

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

SPILL: See ERG Table 1 - Initial Isolation and Protective Action Distances on the UN/NA 3294 datasheet.

FIRE: If tank, rail car or tank truck 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, 2020)
Firefighting
Excerpt from 131 Polymerizable warning [Flammable Liquids - Toxic]:

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient. CAUTION: Methanol (UN1230) will burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.).

SMALL FIRE: Dry chemical, CO2, water spray or 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. Dike runoff from fire control for later disposal. Avoid aiming straight or solid streams directly onto the product.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. 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 engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)
Non-Fire Response
Excerpt from 131 Polymerizable warning [Flammable Liquids - Toxic]:

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 or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors.

SMALL SPILL: Absorb with earth, sand or other non-combustible material and transfer to containers for later disposal. Use clean, non-sparking tools to collect absorbed material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2020)
Protective Clothing
Excerpt from ERG Guide 131 [Flammable Liquids - Toxic]:

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. (ERG, 2020)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Hydrogen cyanide (21°C, liquid) 74-90-8 Liquid 135 >480 135
Hydrogen cyanide (27°C, gaseous) 74-90-8 Vapor 30 >480 >480 >480
Ethanol 64-17-5 Liquid >480 >480 >480 >480 >480
Ethyl alcohol 64-17-5 Liquid >480 >480 >480 >480 >480
Spiritus 64-17-5 Liquid >480 >480 >480 >480 >480
> indicates greater than.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

(DuPont, 2023)

First Aid
Excerpt from 131 Polymerizable warning [Flammable Liquids - Toxic]:

Call 911 or emergency medical service. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air if it can be done safely. Give artificial respiration if victim is not breathing. Do not perform mouth-to-mouth resuscitation if victim ingested or inhaled the substance; wash face and mouth before giving artificial respiration. Use a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. Wash skin with soap and water. In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin. Keep victim calm and warm. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. (ERG, 2020)

Physical Properties

Chemical Formula:
  • HCN (hydrogen cyanide)
  • C2H5OH (ethanol)
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: data unavailable
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: data unavailable
Boiling Point: data unavailable
Molecular Weight: data unavailable
Water Solubility: data unavailable
Ionization Energy/Potential: 13.60 eV [From NPG: Hydrogen cyanide] (NIOSH, 2023)
IDLH: 50 ppm [From NPG: Hydrogen cyanide] (NIOSH, 2023)

AEGLs (Acute Exposure Guideline Levels)

Final AEGLs for Hydrogen cyanide (74-90-8)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 2.5 ppm 17 ppm 27 ppm
30 minutes 2.5 ppm 10 ppm 21 ppm
60 minutes 2 ppm 7.1 ppm 15 ppm
4 hours 1.3 ppm 3.5 ppm 8.6 ppm
8 hours 1 ppm 2.5 ppm 6.6 ppm
(NAC/NRC, 2023)

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
Hydrogen Cyanide (74-90-8) NA 10 ppm 25 ppm
Ethanol (64-17-5) 1800 ppm star-in-circle icon indicates that odor should be detectable near ERPG-1. 3300 ppm 1-flame icon indicates value is 10-49% of LEL. NA LEL = 33000 ppm
NA = not appropriate.
star-in-circle icon indicates that odor should be detectable near ERPG-1.
1-flame icon indicates value is 10-49% of LEL.
(AIHA, 2022)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Hydrogen cyanide; (Hydrocyanic acid) (74-90-8) 2 ppm 7.1 ppm 15 ppm LEL = 56000 ppm
Ethanol: (Ethyl alcohol) (64-17-5) 1800 ppm 3300 ppm 1-flame icon indicates value is 10-49% of LEL. 15000 ppm 1-flame icon indicates value is 10-49% of LEL. LEL = 33000 ppm
1-flame icon indicates value is 10-49% of LEL.
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Cyanide Compounds N106 & 313
Hydrocyanic acid 74-90-8 100 pounds 10 pounds 10 pounds X P063 2500 pounds
Hydrogen cyanide 74-90-8 100 pounds 10 pounds 10 pounds 313 P063 2500 pounds

(EPA List of Lists, 2022)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

RELEASE THEFT SABOTAGE
Chemical of Interest CAS Number Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Hydrocyanic acid 74-90-8 1.00 % 2500 pounds toxic
Hydrogen cyanide; [Hydrocyanic acid] 74-90-8 4.67 % 15 pounds WME

(CISA, 2007)

OSHA Process Safety Management (PSM) Standard List

Chemical Name CAS Number Threshold Quantity (TQ)
Hydrogen Cyanide, Anhydrous 74-90-8 1000 pounds

(OSHA, 2019)

Alternate Chemical Names