# NIOSH Pocket Guide to Chemical Hazards
Propylene glycol monomethyl ether | CAS 107-98-2
CH3OCH2CHCH3 | RTECS UB7700000
Synonyms & Trade Names Dowtherm® 209, 1-Methoxy-2-hydroxypropane, 1-Methoxy-2-propanol, 2-Methoxy-1-methylethanol, Propylene glycol methyl ether | DOT ID & Guide
Exposure Limits | NIOSH REL: TWA 100 ppm (360 mg/m3) ST 150 ppm (540 mg/m3)
OSHA PEL†: none
IDLH N.D. | Conversion 1 ppm = 3.69 mg/m3
Physical Description Clear, colorless liquid with a mild, ethereal odor.
MW: 90.1 | BP: 248°F | FRZ: -139°F (Sets to glass) | Sol: Miscible
VP(77°F): 12 mmHg | IP: ? |  | Sp.Gr: 0.96
Fl.P: 97°F | UEL(calc): 13.8% | LEL(calc.): 1.6% |
Class IC Flammable Liquid: Fl.P. at or above 73°F and below 100°F.
Incompatibilities & Reactivities Oxidizers, strong acids [Note: Hygroscopic (i.e., absorbs moisture from the air). May slowly form reactive peroxides during prolonged storage.]
Measurement Methods OSHA 99
Personal Protection & Sanitation Skin: No recommendation Eyes: Prevent eye contact Wash skin: No recommendation Remove: When wet (flammable) Change: No recommendation | First Aid (See procedures) Eye: Irrigate immediately Skin: Water wash Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations To be added later
Exposure Routes inhalation, ingestion, skin and/or eye contact
Symptoms Irritation eyes, skin, nose, throat; headache, nausea, dizziness, drowsiness, incoordination; vomiting, diarrhea
Target Organs Eyes, skin, respiratory system, central nervous system
See also: INTRODUCTION