NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

Dibutyl phosphate



Synonyms & Trade Names

Dibutyl acid o-phosphate, Di-n-butyl hydrogen phosphate, Dibutyl phosphoric acid
DOT ID & Guide


NIOSH REL: TWA 1 ppm (5 mg/m3) ST 2 ppm (10 mg/m3)
OSHA PEL: TWA 1 ppm (5 mg/m3)
30 ppm See: 107664
1 ppm = 8.60 mg/m3
Physical Description
Pale-amber, odorless liquid.
MW: 210.2
BP: 212°F (Decomposes)
FRZ: ?
Sol: Insoluble
VP: 1 mmHg (approx)
IP: ?

Sp.Gr: 1.06
Fl.P: ?
UEL: ?
LEL: ?

Combustible Liquid
Incompatibilities & Reactivities

Strong oxidizers
Measurement Methods
NIOSH 5017
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet or contaminated
Change: No recommendation
Provide: Quick drench
First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Soap wash promptly
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations
Up to 10 ppm:
(APF = 10) Any supplied-air respirator
Up to 25 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode
Up to 30 ppm:
(APF = 50) Any supplied-air respirator that has a tight-fitting facepiece and is 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
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister having an N100, R100, or P100 filter. Click here for information on selection of N, R, or P filters./Any appropriate escape-type, self-contained breathing apparatus
Important additional information about respirator selection
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Irritation eyes, skin, respiratory system; headache
Target Organs
Eyes, skin, respiratory system
See also: INTRODUCTION   See ICSC CARD: 1278   See MEDICAL TESTS: 0070