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Chemical Sampling Information (CSI)
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General Description

Synonyms: Refrigerant 21; Freon 21; Dichlorofluoromethane; F-21

OSHA IMIS Code Number: 0887

Chemical Abstracts Service (CAS) Registry Number: 75-43-4

NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: PA8400000; 47892

Department of Transportation Regulation Number (49 CFR 172.101): 126 UN1029; Non-Flammable Liquid

Chemical Description and Physical Properties:

colorless liquid or gas with a slight ether-like odor
molecular weight: 103
boiling point: 48°F
melting point: -211°F

Incompatibilities: Chemically active metals: sodium, potassium, calcium, powdered aluminum, zinc, magnesium

Exposure Limits

OSHA Permissible Exposure Limit (PEL):

General Industry: 1000 ppm, 4200 mg/m3

Construction Industry: 1000 ppm, 4200 mg/m3 TWA

American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 10 ppm, 42 mg/m3 TWA

National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): 10 ppm TWA

Health Factors

Potential Symptoms: Asphyxia, cardiac arrhythmias, cardiac arrest

Health Effects: Cumulative liver damage (HE3); Asphyxiant (HE17)

Affected Organs: Respiratory system, CVS

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):

  • sampling media: Two Charcoal Tubes (400/200 mg sections, 20/40 mesh) in series (See note)
    analytical solvent: Carbon Disulfide
    maximum volume: 3 Liters
    maximum flow rate: 0.05 L/min
    current analytical method: Gas Chromatography; GC/FID
    method reference: 1 (NIOSH 2516 [21 KB PDF, 4 pages])
    sampling and analytical error: 0.10
    method classification: Fully Validated
    note: Before sampling, remove the large section of charcoal from one tube and the small section of charcoal from the other tube. Connect the tubes in series so the air passes through the large section of charcoal first.

Secondary Laboratory Sampling/Analytical Method (SAM2):

  • device: Organic Vapor Analyzer
    part #: MIRAN 1A & 1B Min. Det. Con.
    range: 0.08 ppm @ 9.4 um
    classification:     Mfg

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