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2,4-D

Synonyms & Trade Names
Dichlorophenoxyacetic acid; 2,4-Dichlorophenoxyacetic acid
CAS No.
94-75-7
RTECS No.
AG6825000
DOT ID & Guide
2765 152
Formula
Cl2C6H3OCH2COOH
Conversion
IDLH
100 mg/m3
See: 94757
Exposure Limits
NIOSH REL
: TWA 10 mg/m3
OSHA PEL
: TWA 10 mg/m3
Measurement Methods

NIOSH 5001
See: NMAM or OSHA Methods
Physical Description
White to yellow, crystalline, odorless powder. [herbicide]
MW:
221.0
BP:
Decomposes		 MLT: 280°F
Sol:
0.05%		 VP(320°F): 0.4 mmHg
IP:
?
Sp.Gr:
1.57
Fl.P:
NA
UEL:
NA
LEL:
NA
Noncombustible Solid, but may be dissolved in flammable liquids.
Incompatibilities & Reactivities
Strong oxidizers
Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms
lassitude (weakness, exhaustion), stupor, hyporeflexia, muscle twitching; convulsions; dermatitis; in animals: liver, kidney injury
Target Organs
Skin, central nervous system, liver, 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
First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Soap wash promptly
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations

NIOSH/OSHA

Up to 100 mg/m3:
(APF = 10) Any air-purifying half-mask respirator with organic vapor cartridge(s) in combination with an N95, R95, or P95 filter. The following filters may also be used: N99, R99, P99, N100, R100, P100.
Click here for information on selection of N, R, or P filters.
(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.
(APF = 25) Any powered, air-purifying respirator with an organic vapor cartridge in combination with a high-efficiency particulate filter.
(APF = 10) Any supplied-air respirator
(APF = 50) Any self-contained breathing apparatus 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 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

See also: INTRODUCTION   See ICSC CARD: 0033   See MEDICAL TESTS: 0248
 

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