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Ammonia

Synonyms & Trade Names
Anhydrous ammonia, Aqua ammonia, Aqueous ammonia [Note: Often used in an aqueous solution.]
CAS No.
7664-41-7
RTECS No.
BO0875000
DOT ID & Guide
1005 125 (anhydrous)
2672 154 (10-35% solution)
2073 125 (>35-50% solution)
1005 125 (>50% solution)
Formula
NH3
Conversion
1 ppm = 0.70 mg/m3
IDLH
300 ppm
See: 7664417
Exposure Limits
NIOSH REL
: TWA 25 ppm (18 mg/m3) ST 35 ppm (27 mg/m3)
OSHA PEL
†: TWA 50 ppm (35 mg/m3)
Measurement Methods

NIOSH 3800 , 6015 , 6016;
OSHA ID188
See: NMAM or OSHA Methods
Physical Description
Colorless gas with a pungent, suffocating odor. [Note: Shipped as a liquefied compressed gas. Easily liquefied under pressure.]
MW:
17.0
BP:
-28°F
FRZ:
-108°F
Sol:
34%
VP:
8.5 atm
IP:
10.18 eV
Fl.P:
NA (Gas)
UEL:
28%
LEL:
15%
RGasD:
0.60
[Note: Although NH3 does not meet the DOT definition of a Flammable Gas (for labeling purposes), it should be treated as one.]
Incompatibilities & Reactivities
Strong oxidizers, acids, halogens, salts of silver & zinc [Note: Corrosive to copper & galvanized surfaces.]
Exposure Routes
inhalation, ingestion (solution), skin and/or eye contact (solution/liquid)
Symptoms
irritation eyes, nose, throat; dyspnea (breathing difficulty), wheezing, chest pain; pulmonary edema; pink frothy sputum; skin burns, vesiculation; liquid: frostbite
Target Organs
Eyes, skin, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated (solution)
Remove: When wet or contaminated (solution)
Change: No recommendation
Provide: Eyewash (>10%), Quick drench (>10%)
First Aid
(See procedures)
Eye: Irrigate immediately (solution/liquid)
Skin: Water flush immediately (solution/liquid)
Breathing: Respiratory support
Swallow: Medical attention immediately (solution)
Respirator Recommendations

NIOSH

Up to 250 ppm:
(APF = 10) Any chemical cartridge respirator with cartridge(s) providing protection against the compound of concern*
(APF = 10) Any supplied-air respirator*

Up to 300 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*
(APF = 25) Any powered, air-purifying respirator with cartridge(s) providing protection against the compound of concern*
(APF = 50) Any chemical cartridge respirator with a full facepiece and cartridge(s) providing protection against the compound of concern
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted canister providing protection against the compound of concern
(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 canister providing protection against the compound of concern
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also: INTRODUCTION   See ICSC CARD: 0414   See MEDICAL TESTS: 0013
 
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