NIOSH logo and tagline

Oxalic acid

Related Pages
Synonyms & Trade Names
Ethanedioic acid, Oxalic acid (aqueous), Oxalic acid dihydrate
CAS No.
144-62-7
RTECS No.
RO2450000
DOT ID & Guide
Formula
HOOCCOOH • 2H₂O
Conversion
IDLH
500 mg/m3
See: 144627
Exposure Limits
NIOSH REL
TWA 1 mg/m3 ST 2 mg/m3
OSHA PEL
TWA 1 mg/m3 See Appendix G
Measurement Methods
None available
See: NMAM or OSHA Methods
Physical Description
Colorless, odorless powder or granular solid. [Note: The anhydrous form (COOH)2 is an odorless, white solid.]
Molecular Weight
126.1
Boiling Point
Sublimes
Melting Point
215°F (Sublimes)
Solubility
14%
Vapor Pressure
<0.001 mmHg
Ionization Potential
?
Specific Gravity
1.90
Flash Point
?
Upper Explosive Limit
?
Lower Explosive Limit
?
Combustible Solid
Incompatibilities & Reactivities
Strong oxidizers, silver compounds, strong alkalis, chlorites [Note: Gives off water of crystallization at 215°F and begins to sublime.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, mucous membrane; eye burns; localized pain, cyanosis; shock, collapse, convulsions; kidney damage
Target Organs
Eyes, skin, respiratory system, kidneys
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:Daily
Provide:Eyewash
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Water flush promptly
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH/OSHA

Up to 25 mg/m3:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode£
(APF = 25) Any powered, air-purifying respirator with a high-efficiency particulate filter.£

Up to 50 mg/m3:


(APF = 50) Any air-purifying, full-facepiece respirator with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters. 


(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

Up to 500 mg/m3:
(APF = 2000) Any supplied-air respirator that has a full facepiece and is 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 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

See also
INTRODUCTION   ICSC CARD: 0707   MEDICAL TESTS: 0170
Page last reviewed: October 30, 2019
Content source: National Institute for Occupational Safety and Health