# NIOSH Pocket Guide to Chemical Hazards
Ethyl formate | CAS 109-94-4
CH3CH2OCHO | RTECS LQ8400000
Synonyms & Trade Names Ethyl ester of formic acid, Ethyl methanoate | DOT ID & Guide 1190 129
Exposure Limits | NIOSH REL: TWA 100 ppm (300 mg/m3)
OSHA PEL: TWA 100 ppm (300 mg/m3)
IDLH 1500 ppm | Conversion 1 ppm = 3.03 mg/m3
Physical Description Colorless liquid with a fruity odor.
MW: 74.1 | BP: 130°F | FRZ: -113°F | Sol(64°F): 9%
VP: 200 mmHg | IP: 10.61 eV |  | Sp.Gr: 0.92
Fl.P: -4°F | UEL: 16.0% | LEL: 2.8% |
Class IB Flammable Liquid: Fl.P. below 73°F and BP at or above 100°F.
Incompatibilities & Reactivities Nitrates; strong oxidizers, alkalis & acids [Note: Decomposes slowly in water to form ethyl alcohol and formic acid.]
Measurement Methods NIOSH 1452; OSHA 7
Personal Protection & Sanitation 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: Water flush immediately Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations NIOSH/OSHA Up to 1500 ppm: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode£/(APF = 25) Any powered, air-purifying respirator with organic vapor cartridge(s)£/(APF = 50) Any chemical cartridge respirator with a full facepiece and organic vapor cartridge(s)/(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister/(APF = 50) Any self-contained breathing apparatus with a full facepiece/(APF = 50) Any supplied-air respirator with a full facepiece 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
Exposure Routes inhalation, ingestion, skin and/or eye contact
Symptoms Irritation eyes, upper respiratory system; in animals: narcosis
Target Organs Eyes, respiratory system, central nervous system
See also: INTRODUCTION