Page 216 - Handbook of Hazardous Chemical Properties

206 HYDROGEN, LIQUEFIED

Chemical Reactivity - Reactivity with Water: Dissolves with a moderate reaction; Reactivity with
Common Materials: None; Stability During Transport: May become unstable and subject to explosion
if stored for extended periods of time or is exposed to high temperatures and pressures; Neutmlizing
Agents for Acids and Caustics: The weak acidity can be neutralized by slaked lime, however this does
not destroy the hazardous properties of the material; Polymerization: Not pertinent; Inhibitor of
Polymerization: Not pertinent.

HYDROGEN FLUORIDE
Chemical Designations - Synonyms: Hydrofluoric acid, anhydrous; Chemical Fomla: &F2,
Observable Characteristics - Physical State (as shipped) : Liquid; Color: Colorless; Odor: pungent,
irritating.
Physical and Chemical Properties - Physical State at 15 "c and I am. : Liquid; Molecular Weight:
20.01; Boiling Point at I m.: 67.1, 19.5, 292.7; Freezing Point: -134, -92.2, 181.0; Critical
Temperature: 447,230.6,503.8; Critical Pressure: 1100,74.8,7.58; Specific Gravity: 0.992 at 19 "C
(liquid); Vapor (Gas) Specific Gravity: 0.7; Ratio of Specific Heats of Vapor (Gas): 1.399; Latent Heat
of Vaporization: 145, 80.85, 3.37; Heat of Combustion: Not pertinent; Heat of Decomposition: Not
pertinent.
Health Hazards Information - Recommended Personal Protective Equipment: Acid-resistant hat,
safety goggles, face shield, jacket, overalls, gauntlet-type gloves, and boots. The goggles and face
shield must have plastic lenses. There must be a shower and eye wash. Observe all precautions in the
Manufacturing Chemists Association Chemical Safety Data Sheet SD-25; Symptoms Following
Exposure: Serious and painful burns of eyes, skin and respiratory tract; pulmonary edema; General
Treatment for Exposure: INGESTION: have victim drink water or milk; do NOT induce vomiting.
SKIN: flush with water; consult physician. EYES: flush with water for at least 15 min.; consult
physician; Toxicity by Inhalation (Threshold Limit Value) : 3 ppm; Short-Tenn Inhalation Limits: 3 ppm
for 15 min.; Toxicity by Ingestion: Oral LD, = 80 mg/kg (guinea pig); Late Toxicity: Data not
available; Vapor (Gas) Irritant Characteristics: Vapors cause severe irritation of eye and throat and can
cause eye and lung injury. They cannot be tolerated even at low concentrations; Liquid or Solid Irritant
Characteristics: Severe skin irritant. Causes second- and third-degree burns on short contact; very
injurious to the eyes; Odor Threshold 0.03 mg/m3.
Fire Hazards - Flash Point : Not flammable; Flammable Limits in Air (I): flammable; Fire
Not
Extinguishing Agents: Not pertinent; Fire Extinguishing Agents Not To Be Used: Not pertinent; Special
Hazards of Combustion Products: Toxic and irritating vapors are generated when exposed to hear;
Behavior in Fire: Not pertinent; Ignition Temperature : Not flammable; Electrical Hazard: Not
pertinent; Burning Rate: Not flammable.
Chemical Reactivity - Reactivity with Water: Dissolves with liberation of heat; Reactivity with
Common Materials: Will attack glass, concrete and certain metals containing silica, such as cast iron.
Will attack natural rubber, leather, and many organic materials. Can generate flammable and explosive
hydrogen when in contact with some metals; Stability During Tmport: Stable but requires special
packaging; Neutralizing Agents for Acids and Caustics: Flush with water and apply powdered
limestone, slaked lime, soda ash, or sodium bicarbonate; Polymerization: Not pertinent; Inhibitor of
Polymerizm'on: Not pertinent.

HYDROGEN, LIQUEFIED
Chemical Designations - Synonyms: Liquid hydrogen; para Hydrogen; Chemical Fonnuh: H2.
Observable Characteristics - Physical State (as shipped): Liquid; Color: Colorless; Odor: None.
Physical and Chemical Properties - Physical State at 15 "c and I ah. : Gas; Molecular Weight: 2.0;
Boiling Point at I atm.: -423, -253, 20; Freezing Point: -434, -259, 14; Critical Temperature: -400,
-240,33; Critical Pressure: 188, 12.8, 1.30; Specific Gravity: 0.071 at -253 "C (liquid); Vapor (Gas)
Specific Gravity: 0.067; Ratio of Specific Heats of Vapor (h): Latent Heat of Vaporization:
1.3962;
190.5, 105.8, 4.427; Heat of Combustion: -50,080, -27,823, -1164.1; Heat of Decomposition: Not
pertinent.