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Hydrogen Cyanide Chemical Sampling Information
Hydrogen Cyanide
General Description
    Synonyms: Hydrocyanic acid; Prussic acid; Formonitrile; HCN

    OSHA IMIS Code Number: 1440

    Chemical Abstracts Service (CAS) Registry Number: 74-90-8

    NIOSH, Registry of Toxic Effects (RTECS) Identification Number: MW6825000

    Department of Transportation Regulation Number (49 CFR 172.101) and Guide: 1051 117 (>20% solution); 1051 117 (anhydrous); 1613 154 (≤20% solution)

    NIOSH Pocket Guide to Chemical Hazards, Hydrogen Cyanide: chemical description, physical properties, potentially hazardous incompatibilities, and more
Exposure Limits
    OSHA Permissible Exposure Limit (PEL) for General Industry: 29 CFR 1910.1000 Z-1 Table -- 10 ppm, 11 mg/m3 TWA; Skin

    OSHA Permissible Exposure Limit (PEL) for Construction Industry: 29 CFR 1926.55 Appendix A -- 10 ppm, 11 mg/m3 TWA; Skin

    OSHA Permissible Exposure Limit (PEL) for Maritime: 29 CFR 1915.1000 Table Z-Shipyards -- 10 ppm, 11 mg/m3 TWA; Skin

    American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 4.7 ppm, 5 mg/m3 Ceiling; Skin

    National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): 4.7 ppm, 5 mg/m3 STEL; Skin
Health Factors
    Environmental Protection Agency (EPA) carcinogenic classification: Group D, not classifiable as to human carcinogenicity

    NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 50 ppm

    Potential symptoms: Asphyxia and death at high levels, preceded by seizures, coma with abolished deep reflexes and dilated pupils, paralysis; weakness; dizziness; numbness; tremor; loss of visual acuity; headaches; nausea, vomiting; loss of appetite, weight loss; increased rate and depth of respiration, or slow and gasping respiration; eye irritation; rash, chemical burns on skin; enlargement of thyroid gland

    Health Effects: Acute Systemic Toxicity (HE4); Cumulative systemic toxicity---weight loss (HE3); Irritation-Eyes, Skin---skin lesions

    Affected organs: CNS, cardiovascular system, thyroid, eyes, skin

    Notes:
    1. Fatal concentrations in air that have been reported for various exposure times are 109 ppm for one hour, 182 ppm for 10 minutes, and 364 ppm for 2 minutes.
    2. Neurological sequelae in survivors of acute cyanide poisoning include parkinsonism and dystonia.
    3. Regulated by OSHA under 29 CFR 1910.119 (Process safety management of highly hazardous chemicals).

    Date Last Revised: 06/30/2003

    Literature Basis:
    • (symptoms)
      Agency for Toxic Substances and Disease Registry (ATSDR): Toxicological Profile for Cyanide (Update). PHS, U.S. DHHS, Atlanta, GA, 1997.
    • U.S. EPA Technology Transfer Network Air Toxics Website: Cyanide Compounds.
    • (fatal concentrations; conversion factor, 1 ppm=1.10 mg/m3)
      NIOSH Registry of Toxic Effects of Chemical Substances: Hydrocyanic acid.
    • (neurological sequelae)
      Albin, R.L.: Basal ganglia neurotoxins. Neurol. Clin. 18(3): 665-680, 2000.
Monitoring Methods used by OSHA
    Laboratory Sampling/Analytical Method:

    • sampling media: Mixed Cellulose Ester Filter (MCEF) 0.8 microns in series with Midget Fritted Glass Bubbler (MFGB) containing 10 mL 0.1 N NaOH
      maximum volume: 120 Liters   maximum flow rate: 1.0 L/min
      current analytical method: Ion Specific Electrode; ISE
      method reference: OSHA Analytical Method (OSHA ID-120)
      method classification: Fully Validated
      note: Submit as a separate sample. If present, sulfide should be listed as an interference. Particulate cyanide, if present (see Cyanide (as CN)), is collected on the filter. HCN is collected in the Midget Fritted Glass Bubbler. Within 1 hour after the sample has been collected, transfer the filter to a clean screw cap vial containing 10 mL 0.1 N of NaOH.

    • sampling media: Mixed Cellulose Ester Filter (MCEF) 0.8 microns in series with Soda Lime sampling tube (600/200 mg)
      maximum volume: 90 Liters   maximum flow rate: 0.2 L/min
      current analytical method: Ion Specific Electrode; ISE
      method reference: Modification of NIOSH Method (NIOSH 6010) with OSHA Method ID-120
      method classification: Fully Validated
      note: Submit as a separate sample. If present, sulfide should be listed as an interference. Particulate cyanide, if present (see Cyanide (as CN)), is collected on the filter. HCN is collected on the Soda Lime sampling tube. Within 1 hour after the sample has been collected, transfer the filter to a clean screw cap vial containing 10 mL of 0.1 N NaOH.

    On-Site Sampling Techniques/Methods:

    • device: Detector Tube
      manufacturer: AUER/MSA
      model/type: HCN-2, MSA P/N 803945, AUER P/N 5085-824
      sampling information: follow manufacturer’s instructions
      upper measurement limit: 50 ppm
      detection limit: approx. 2 ppm
      overall uncertainty: unknown
      method reference: on-site air secondary (manufacturer)

    • device: Detector Tube
      manufacturer: Gastec
      model/type: 12LL
      sampling information: 2 strokes
      upper measurement limit: 7 ppm
      detection limit: 0.05 ppm
      overall uncertainty: 16% for 0.2 to 2 ppm, 8% for 3 to 7 ppm
      method reference: on-site air secondary (manufacturer)

    • device: Detector Tube
      manufacturer: Gastec
      model/type: 12L
      sampling information: 0.5 to 5 strokes
      upper measurement limit: 120 ppm
      detection limit: 0.1 ppm
      overall uncertainty: 16% for 2.5 to 20 ppm, 8% for 20 to 60 ppm
      method reference: on-site air secondary (manufacturer)

    • device: Detector Tube
      manufacturer: Gastec
      model/type: 12M
      sampling information: 0.5 to 2 strokes
      upper measurement limit: 2400 ppm
      detection limit: 1 ppm
      overall uncertainty: 16% for 50 to 200 ppm, 8% for 200 to 800 ppm
      method reference: on-site air secondary (manufacturer)

    • device: Detector Tube
      manufacturer: Gastec
      model/type: 12H
      sampling information: 1 stroke
      upper measurement limit: 1.6%
      detection limit: 0.005%
      overall uncertainty: 16% for 0.05 to 0.4%, 8% for 0.4 to 2%
      method reference: on-site air secondary (manufacturer)

    • device: Detector Tube
      manufacturer: Matheson-Kitagawa
      model/type: 8014-112SB
      sampling information: follow manufacturer’s instructions
      upper measurement limit: 100 ppm
      detection limit: approx. 0.5 ppm
      overall uncertainty: unknown
      method reference: on-site air secondary (manufacturer)

    • device: Detector Tube
      manufacturer: Matheson-Kitagawa
      model/type: 8014-112SA
      sampling information: follow manufacturer’s instructions
      upper measurement limit: 3.0%
      detection limit: approx. 0.01%
      overall uncertainty: unknown
      method reference: on-site air secondary (manufacturer)

    Wipe sampling: No
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 Safety and Health
 Topics
 
  Chemical Sampling Information:
  Hydrogen Cyanide
  General Description
  Exposure Limits
  Health Factors
  Monitoring
     
 
 
Page last updated: 03/26/2007
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