# NIOSH Pocket Guide to Chemical Hazards
Potassium cyanide (as CN) | CAS 151-50-8
KCN | RTECS TS8750000
Synonyms & Trade Names Potassium salt of hydrocyanic acid | DOT ID & Guide 1680 157
Exposure Limits | NIOSH REL*: C 5 mg/m3 (4.7 ppm) [10-minute] [*Note: The REL also applies to other cyanides (as CN) except Hydrogen cyanide.]
OSHA PEL*: TWA 5 mg/m3 [*Note: The PEL also applies to other cyanides (as CN) except Hydrogen cyanide.]
IDLH 25 mg/m3 (as CN) | Conversion
Physical Description White, granular or crystalline solid with a faint, almond-like odor.
MW: 65.1 | BP: 2957°F | MLT: 1173°F | Sol(77°F): 72%
VP: 0 mmHg (approx) | IP: NA |  | Sp.Gr: 1.55
Fl.P: NA | UEL: NA | LEL: NA |
Noncombustible Solid, but contact with acids releases highly flammable hydrogen cyanide.
Incompatibilities & Reactivities Strong oxidizers (such as acids, acid salts, chlorates & nitrates) [Note: Absorbs moisture from the air forming a syrup.]
Measurement Methods NIOSH 6010, 7904
Personal Protection & Sanitation Skin: Prevent skin contact Eyes: Prevent eye contact Wash skin: When contaminated Remove: When wet or contaminated Change: Daily Provide: Eyewash, Quick drench | First Aid (See procedures) Eye: Irrigate immediately Skin: Soap wash immediately Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations NIOSH/OSHA Up to 25 mg/m3: (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 canister providing protection against the compound of concern and having 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 Irritation eyes, skin, upper respiratory system; asphyxia; lassitude (weakness, exhaustion), headache, confusion; nausea, vomiting; increased respiratory rate, slow gasping respiration; thyroid, blood changes
Target Organs Eyes, skin, respiratory system, cardiovascular system, central nervous system, thyroid, blood
See also: INTRODUCTION