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Chemical Datasheet

SILANE

2.1 - Flammable gas

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7803-62-5   (SILANE)
  • 2203
  • Flammable Gas
none
NIOSH Pocket Guide International Chem Safety Card
Silicon tetrahydride
  • SILANE
NFPA 704
Diamond Hazard Value Description
4
1 3
Blue Health 1 Can cause significant irritation.
Red Flammability 4 Burns readily. Rapidly or completely vaporizes at atmospheric pressure and normal ambient temperature.
Yellow Instability 3 Capable of detonation or explosive decomposition or explosive reaction but requires a strong initiating source or must be heated under confinement before initiation.
White Special
(NFPA, 2010)
General Description
Silane is a colorless, flammable and poisonous gas, with a strong repulsive odor. It is easily ignited in air, reacts with oxidizing agents, is very toxic by inhalation, and is a strong irritant to skin, eyes and mucous membranes. Silane is lighter than air. Under prolonged exposure to fire or heat the containers may rupture violently and rocket. It is used in the production of amorphous silicon.

Hazards

Reactivity Alerts
Air & Water Reactions
Highly flammable. Pure state ignites in air, the first seven to eight of the series 6H2n+1 ignite spontaneously in air at room temperature or slightly elevated temperatures [Mellor 1:376 1946-47]. Slowly reacts with water to form silicon hydroxides and hydrogen gas.
Fire Hazard
Excerpt from 116 Polymerizable warning [Gases - Flammable (Unstable)]:

EXTREMELY FLAMMABLE. Will be easily ignited by heat, sparks or flames. Will form explosive mixtures with air. Acetylene (UN1001, UN3374) may react explosively even in the absence of air. Silane (UN2203) will ignite spontaneously in air. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Vapors from liquefied gas are initially heavier than air and spread along ground. Vapors may travel to source of ignition and flash back. Cylinders exposed to fire may vent and release flammable gas through pressure relief devices. Containers may explode when heated. Ruptured cylinders may rocket. (ERG, 2020)
Health Hazard
Excerpt from 116 Polymerizable warning [Gases - Flammable (Unstable)]:

Vapors may cause dizziness or asphyxiation without warning. Some may be toxic if inhaled at high concentrations. Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite. Fire may produce irritating and/or toxic gases. (ERG, 2020)
Reactivity Profile
Slowly reacts with water to form silicon hydroxides and hydrogen gas [Hydrides of the Elements of Main Groups I - IV 1971 p.513]. Silane burns in contact with bromine, chlorine or covalent chlorides (carbonyl chloride, antimony pentachloride, tin(IV) chloride). Even traces of the free halogens may cause violent explosions, when handling silane, extreme caution should be taken, [Mellor, 1940, Vol. 6, 220]. Mixtures of silane and nitrogen oxides, nitrous oxide, detonate very easily, [Chem. Abs., 1990, 112, 121711].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from 116 Polymerizable warning [Gases - Flammable (Unstable)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 100 meters (330 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 800 meters (1/2 mile).

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 1600 meters (1 mile) in all directions; also, consider initial evacuation for 1600 meters (1 mile) in all directions. (ERG, 2020)
Firefighting
Excerpt from 116 Polymerizable warning [Gases - Flammable (Unstable)]:

DO NOT EXTINGUISH A LEAKING GAS FIRE UNLESS LEAK CAN BE STOPPED.

SMALL FIRE: Dry chemical or CO2.

LARGE FIRE: Water spray or fog. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING TANKS: 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. Do not direct water at source of leak or safety devices; icing may occur. 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 116 Polymerizable warning [Gases - Flammable (Unstable)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Stop leak if you can do it without risk. Do not touch or walk through spilled material. Do not direct water at spill or source of leak. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. If possible, turn leaking containers so that gas escapes rather than liquid. Prevent entry into waterways, sewers, basements or confined areas. Isolate area until gas has dispersed. (ERG, 2020)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Silicon tetrahydride:

Skin: No recommendation is made specifying the need for personal protective equipment for the body.

Eyes: No recommendation is made specifying the need for eye protection.

Wash skin: No recommendation is made specifying the need for washing the substance from the skin (either immediately or at the end of the work shift).

Remove: No recommendation is made specifying the need for removing clothing that becomes wet or contaminated.

Change: No recommendation is made specifying the need for the worker to change clothing after the workshift. (NIOSH, 2023)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Silane 7803-62-5 Vapor >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 NIOSH Pocket Guide for Silicon tetrahydride:

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible. (NIOSH, 2023)

Physical Properties

Chemical Formula:
  • H4Si
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: -301°F (NIOSH, 2023)
Vapor Pressure: greater than 1 atm (NIOSH, 2023)
Vapor Density (Relative to Air): 1.11 (NIOSH, 2023) - Heavier than air; will sink
Specific Gravity: data unavailable
Boiling Point: -169°F at 760 mmHg (NIOSH, 2023)
Molecular Weight: 32.1 (NIOSH, 2023)
Water Solubility: Decomposes (NIOSH, 2023)
Ionization Energy/Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

Interim AEGLs for Silane (7803-62-5)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 100 ppm 170 ppm 300 ppm
30 minutes 100 ppm 170 ppm 300 ppm
60 minutes 100 ppm 130 ppm 270 ppm
4 hours NR 80 ppm 170 ppm
8 hours NR 42 ppm 80 ppm
NR = Not recommended due to insufficient data
(NAC/NRC, 2023)

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Silane; (Silicon tetrahydride) (7803-62-5) 100 ppm 130 ppm 270 ppm LEL = 14000 ppm
(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
Silane 7803-62-5 10000 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
Silane 7803-62-5 1.00 % 10000 pounds flammable

(CISA, 2007)

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names