# NIOSH Pocket Guide to Chemical Hazards
Triorthocresyl phosphate | CAS 78-30-8
(CH3C6H40)3PO | RTECS TD0350000
Synonyms & Trade Names TCP, TOCP, Tri-o-cresyl ester of phosphoric acid, Tri-o-cresyl phosphate | DOT ID & Guide 2574 151
Exposure Limits | NIOSH REL: TWA 0.1 mg/m3 [skin]
OSHA PEL†: TWA 0.1 mg/m3
IDLH 40 mg/m3 | Conversion
Physical Description Colorless to pale-yellow, odorless liquid or solid (below 52°F).
MW: 368.4 | BP: 770°F (Decomposes) | FRZ: 52°F | Sol: Slight
VP(77°F): 0.00002 | IP: ? |  | Sp.Gr: 1.20
Fl.P: 437°F | UEL: ? | LEL: ? |
Class IIIB Combustible Liquid: Fl.P. at or above 200°F.
Incompatibilities & Reactivities Oxidizers
Measurement Methods NIOSH 5037
Personal Protection & Sanitation Skin: Prevent skin contact Eyes: No recommendation Wash skin: When contaminated Remove: When wet or contaminated Change: No recommendation | First Aid (See procedures) Eye: Irrigate immediately Skin: Soap wash immediately Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations NIOSH/OSHA Up to 0.5 mg/m3: (APF = 5) Any dust and mist respirator Up to 1 mg/m3: (APF = 10) Any dust and mist respirator except single-use and quarter-mask respirators/(APF = 10) Any supplied-air respirator Up to 2.5 mg/m3: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode/(APF = 25) Any powered, air-purifying respirator with a dust and mist filter Up to 5 mg/m3: (APF = 50) Any air-purifying, full-facepiece respirator with a high-efficiency particulate filter/(APF = 50) Any supplied-air respirator that has a tight-fitting facepiece and is operated in a continuous-flow mode/(APF = 50) Any powered, air-purifying respirator with a tight-fitting facepiece and a high-efficiency particulate filter/(APF = 50) Any self-contained breathing apparatus with a full facepiece/(APF = 50) Any supplied-air respirator with a full facepiece Up to 40 mg/m3: (APF = 1000) Any supplied-air respirator operated in a pressure-demand or other positive-pressure mode 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 with a high-efficiency particulate filter/Any appropriate escape-type, self-contained breathing apparatus
Exposure Routes inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms Gastrointestinal disturbance; peripheral neuropathy; cramps in calves, paresthesia in feet or hands; weak feet, wrist drop, paralysis
Target Organs peripheral nervous system, central nervous system
See also: INTRODUCTION