# NIOSH Pocket Guide to Chemical Hazards
n-Pentane | CAS 109-66-0
CH3[CH2]3CH3 | RTECS RZ9450000
Synonyms & Trade Names Pentane, normal-Pentane | DOT ID & Guide 1265 128
Exposure Limits | NIOSH REL: TWA 120 ppm (350 mg/m3) C 610 ppm (1800 mg/m3) [15-minute]
OSHA PEL†: TWA 1000 ppm (2950 mg/m3)
IDLH 1500 ppm [10%LEL] | Conversion 1 ppm = 2.95 mg/m3
Physical Description Colorless liquid with a gasoline-like odor. [Note: A gas above 97°F. May be utilized as a fuel.]
MW: 72.2 | BP: 97°F | FRZ: -202°F | Sol: 0.04%
VP: 420 mmHg | IP: 10.34 eV |  | Sp.Gr: 0.63
Fl.P: -57°F | UEL: 7.8% | LEL: 1.5% |
Class IA Flammable Liquid: Fl.P. below 73°F and BP below 100°F.
Incompatibilities & Reactivities Strong oxidizers
Measurement Methods NIOSH 1500; 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 wash promptly Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations NIOSH Up to 1200 ppm: (APF = 10) Any supplied-air respirator Up to 1500 ppm: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode/(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, skin, nose; dermatitis; chemical pneumonitis (aspiration liquid); drowsiness; in animals: narcosis
Target Organs Eyes, skin, respiratory system, central nervous system
See also: INTRODUCTION