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Ethyl silicate

Synonyms & Trade Names
Ethyl orthosilicate, Ethyl silicate (condensed), Tetraethoxysilane, Tetraethyl orthosilicate, Tetraethyl silicate
CAS No.
78-10-4
RTECS No.
DOT ID & Guide
1292 129
Formula
(C₂H₅)₄SiO₄
Conversion
1 ppm = 8.52 mg/m3
IDLH
700 ppm
See: 78104
Exposure Limits
NIOSH REL
TWA 10 ppm (85 mg/m3)
OSHA PEL
TWA 100 ppm (850 mg/m3) See Appendix G
Measurement Methods
NIOSH S264 (II-3)
See: NMAM or OSHA Methods
Physical Description
Colorless liquid with a sharp, alcohol-like odor.
Molecular Weight
208.3
Boiling Point
336°F
Freezing Point
-117°F
Solubility
Reacts
Vapor Pressure
1 mmHg
Ionization Potential
9.77 eV
Specific Gravity
0.93
Flash Point
99°F
Upper Explosive Limit
?
Lower Explosive Limit
?
Class IC Flammable Liquid: Fl.P. at or above 73°F and below 100°F.
Incompatibilities & Reactivities
Strong oxidizers, water [Note: Reacts with water to form a silicone adhesive (a milky-white mass).]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, nose; In Animals: lacrimation (discharge of tears); dyspnea (breathing difficulty), pulmonary edema; tremor, narcosis; liver, kidney damage; anemia
Target Organs
Eyes, respiratory system, liver, kidneys, blood, skin
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet (flammable)
Change:No recommendation
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash promptly
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH

Up to 100 ppm:
(APF = 10) Any supplied-air respirator*

Up to 250 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*

Up to 500 ppm:
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

Up to 700 ppm:
(APF = 2000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode

Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0333
Page last reviewed: October 30, 2019