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Compressed Gas: Toxic and Hazardous Gas Classifications

Last updated September 2, 2009 9:14:00 AM PDT
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Check this table to determine the hazard classification of a gas for UCSD facilities.

UCSD Toxic and Hazardous Gas Classifications*
(See abbreviations and footnotes at bottom.)
Gas and Formula
CAS and UN or NA No.
UBC / CFC Class1
UCSD Class2
IDLH 3
LC504
PEL5
Ammonia – NH3 7664–41–7, UN1005 Corrosive6,7,
flammable
III
 300 ppm 4000 ppm 50 ppm
Arsine – AsH3 7784–42–1, UN2188 Highly toxic,
flammable
I
 3 ppm 20 ppm 0.05 ppm
Boron Tribromide – Bbr3 10294–33–4, UN2692 Toxic
II
 50 ppm 380 ppm 1 ppm5(C)
Boron Trichloride – BCl3 10294–34–5, UN1741 Corrosive6
III
 25 ppm8 2541 ppm 5 ppm
Boron Trifluoride – BF3 7637–07–2, UN1008 Toxic
II
 25 ppm 806 ppm 1 ppm5(C)
Bromine – Br2 7726–95–6, UN1744 Highly toxic,
corrosive,
oxidizer
I
 3 ppm 113 ppm 0.1 ppm
Carbon Monoxide – CO 630–08–0, UN1016 Flammable6
III
 1200 ppm 3760 ppm 50 ppm
Chlorine – Cl2 7782–50–5, UN1017 Toxic,
corrosive,
oxidizer
II
 10 ppm 293 ppm 1 ppm5(C)
Chlorine Dioxide – ClO2 10049–04–4, NA9191 Toxic,
oxidizer
II
 5 ppm 250 ppm 0.1 ppm
Chlorine Trifluoride – ClF3 7790–91–2, UN1749 Toxic,
oxidizer
II
 20 ppm 299 ppm 0.1 ppm5(C)
Diborane – B2H6 19278–45–7, UN1911 Highly toxic,
flammable
I
 15 ppm 80 ppm 0.1 ppm
Dichlorosilane – SiH2Cl2 (HCl) 4109–96–0, UN2189 Toxic,
corrosive,
flammable
II
 50 ppm 314 ppm 5 ppm5(C)
Ethylene Oxide – C2H40 75–21–8, UN1040 Flammable6
III
 800 ppm 4350 ppm 1 ppm
Fluorine – F2 7782–41–4, UN1045 Highly toxic,
oxidizer
I
 25 ppm 185 ppm 0.1 ppm
Germane – GeH4 7782–65–2, UN2192 Toxic,
flammable
II
 6 ppm8 622 ppm 0.2 ppm9
Hydrogen Bromide – HBr 10035–10–6, UN1048 Corrosive6
III
 30 ppm 2860 ppm 3 ppm
Hydrogen Chloride – HCl 7647–01–0, UN1050 Corrosive6
III
 50 ppm 2810 ppm 5 ppm5(C)
Hydrogen Cyanide – HCN 74–90–8, UN1051 Highly toxic,
flammable
I
 50 ppm 40 ppm 10 ppm
Hydrogen Fluoride – HF 7664–39–3, UN1052 Toxic
II
 30 ppm 1300 ppm 3 ppm
Hydrogen Selenide – H2Se 7783–07–5, UN2202 Highly toxic,
flammable
I
 1 ppm 2 ppm 0.05 ppm
Hydrogen Sulfide – H2S 7783–06–4, UN1053 Toxic,
flammable
II
 100 ppm 712 ppm 20 ppm
Methyl Bromide – CH3Br 74–83–9, UN1062 Toxic,
flammable
II
 250 ppm 1007 ppm 20 ppm5(C)
Methylisocyanate – CH3NCO 624–83–9, UN2480 Highly toxic,
flammable
I
 3 ppm 22 ppm 0.02 ppm
Methyl Mercaptan – CH3SH 74–93–1, UN1064 Toxic,
flammable
II
 150 ppm 1350 ppm 10 ppm5(C)
Nickel Carbonyl – Ni(CO)4 13463–39–3, UN1259 Highly toxic,
flammable
I
 2 ppm 18 ppm 0.001 ppm
Nitric Oxide – NO 10102–43–9, UN1660 Highly toxic,
oxidizer
I
 100 ppm 115 ppm 25 ppm
Nitrogen Dioxide – NO2 10102–44–0, UN1067 Highly toxic,
oxidizer
I
 20 ppm 115 ppm 5 ppm5(C)
Phosgene – COCl2 75–44–5, UN1076 Highly toxic
I
 2 ppm 5 ppm 0.1 ppm
Phosphine – PH3 7803–51–2, UN2199 Highly toxic,
pyrophoric
I
 50 ppm 20 ppm 0.3 ppm
Phosphorus Oxychloride – POCl3 10025–87–3, UN1810 Highly toxic
I
 0.96 ppm8 96 ppm 0.1 ppm9
Phosphorus Pentafluoride – PF 5 7647–19–0, UN2198 Toxic,
oxidizer
II
 2.6 ppm8 260 ppm 3 ppm
Phosphorus Trichloride – PCl3 7719–12–2, UN1809 Toxic,
oxidizer
II
 25 ppm 208 ppm 0.5 ppm
Selenium Hexafluoride – SeF6 7783–79–1, UN2194 Highly toxic
I
 2 ppm 50 ppm 0.05 ppm (as Se)
Silicon Tetrachloride – SiCl4 (HCl) 10026–04–7, UN1818 Toxic,
corrosive
II
 50 ppm 750 ppm 5 ppm5(C)
Silicon Tetrafluoride – SiF4 (HF) 7783–61–1, UN1859 Toxic
II
 30 ppm 450 ppm 0.1 ppm
Stibine – SbH3 7803–52–3, UN2676 Highly toxic,
flammable
I
 5 ppm 20 ppm 0.1 ppm
Sulfur Dioxide – SO2 7446–09–5, UN1079 Corrosive6
III
 100 ppm 2520 ppm 5 ppm
Sulfuryl Fluoride – SO 2F2 2699–79–8, UN2191 Corrosive6
III
 200 ppm 3020 ppm 5 ppm
Tellurium Hexafluoride – TeF6 7783–80–4, UN2195 Highly toxic
I
 1 ppm 25 ppm 0.02 ppm (as Te)
Titanium Tetrachloride – TiCl4 7550–45–0, UN1838 Highly toxic,
corrosive
I
 1.3 ppm 119 ppm
—
Tungsten Hexafluoride – WF6 (HF) 7783–82–6, UN2196 Toxic,
corrosive
II
 30 ppm 217 ppm 0.1 ppm

(Table adapted from Santa Clara County's Hazardous Gas Table.)

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Footnotes

  1. UBC/ CFC Class:
    • UBC (Uniform Building Code)
    • CFC (California Fire Code)
    • Class as defined in CFC:
      • Health hazards per Article 2
      • Highly toxic = < 200 LC50
      • Toxic = 201–2000 LC50
    • Physical hazards per CFC Standard 7903.
  2. UCSD Hazard Class defined as:
    • Class I = < 200 LC50
    • Class II = 201–2000 LC50
    • Class III = 2001–5000 LC50
  3. IDLH values published in 1994 by the National Institute for Occupational Safety and Health (NIOSH).
  4. LC50 data: Lowest reported value, 1 hour adjusted, taken from Dept. of Transportation, Compressed Gas Association, Registry of Toxic Effects of Chemical Substances.
  5. PEL (Permissible Exposure Limit) values published by Occupational Safety & Health Administration (OSHA), 29 Code of Federal Regulations, Part 1910.1000, Table Z–1, 7/1/95. OSHA values used if available; otherwise, Threshold Limit Values (TLV) from American Conference of Governmental Industrial Hygienists (ACGIH) or Cal/Occupational Safety & Health Administration (Cal/OSHA) values used.
    (C) = TLV-ceiling limit, an exposure limit not to be exceeded under any circumstances.
  6. Moderately toxic as adopted by the cities of San Jose, Santa Clara, and Milpitas: LC50 = 2,000–5000.
  7. When used as a refrigerant, Uniform Building Code Class does not apply.
  8. IDLH determined by 0.01 of LC50.
  9. Cal/OSHA PEL, Title 8, Section 5155, 9/1/95.

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Contacts

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Departments

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See Also

Material Safety Data Sheet (MSDS) Sources