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Trimethyl phosphite

Synonyms & Trade Names
Methyl phosphite, Trimethoxyphosphine, Trimethyl ester of phosphorous acid
CAS No.
121-45-9
RTECS No.
DOT ID & Guide
2329 130
Formula
(CH₃O)₃P
Conversion
1 ppm = 5.08 mg/m3
IDLH
N.D.
See: IDLH INDEX
Exposure Limits
NIOSH REL
TWA 2 ppm (10 mg/m3)
OSHA PEL
none See Appendix G
Measurement Methods
None available
See: NMAM or OSHA Methods
Physical Description
Colorless liquid with a distinctive, pungent odor.
Molecular Weight
124.1
Boiling Point
232°F
Freezing Point
-108°F
Solubility
Reacts
Vapor Pressure
(77°F): 24 mmHg
Ionization Potential
?
Specific Gravity
1.05
Flash Point
82°F
Upper Explosive Limit
?
Lower Explosive Limit
?
Class IC Flammable Liquid: Fl.P. at or above 73°F and below 100°F.
Incompatibilities & Reactivities
Magnesium perchlorate, water [Note: Reacts (hydrolyzes) with water.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, upper respiratory system; dermatitis; In Animals: teratogenic effects
Target Organs
Eyes, skin, respiratory system, reproductive system
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
Provide:Quick drench
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
See also
INTRODUCTION   ICSC CARD: 1556
Page last reviewed: October 30, 2019