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Methyl iodide																				Related Pages
Synonyms & Trade Names
			Iodomethane, Monoiodomethane
CAS No.
			74-88-4
	RTECS No.
			PA9450000
	DOT ID & Guide
			2644 151

FormulaCH3I
	Conversion
			1 ppm = 5.80 mg/m3
	IDLH
			Ca [100 ppm]See: 74884

Exposure Limits
			NIOSH RELCa TWA 2 ppm (10 mg/m3) [skin] See Appendix A
					OSHA PEL TWA 5 ppm (28 mg/m3) [skin]
	Measurement Methods
			**NIOSH** 1014
					
					See: NMAM or OSHA Methods
										
Physical Description
			Colorless liquid with a pungent, ether-like odor.
					[Note: Turns yellow, red, or brown on exposure to light & moisture.]													
										
Molecular Weight141.9	
	Boiling Point109°F
	Freezing Point-88°F
	Solubility1%
	Vapor Pressure400 mmHg
	Ionization Potential9.54 eV											
Specific Gravity2.28	
	Flash PointNA
	Upper Explosive LimitNA
	Lower Explosive LimitNA
Noncombustible Liquid
Incompatibilities & Reactivities
			Strong oxidizers
					[Note: Decomposes at 518°F.]
Exposure Routes
			inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms
			irritation eyes, skin, respiratory system; nausea, vomiting; dizziness, ataxia; slurred speech, drowsiness; dermatitis; [potential occupational carcinogen]
Target Organs
			Eyes, skin, respiratory system, central nervous system
Cancer Site[in animals: lung, kidney & forestomach tumors]										
Personal Protection/Sanitation
			(See protection codes) **Skin:**Prevent skin contact
							**Eyes:**Prevent eye contact
							**Wash skin:**When contaminated
							**Remove:**When wet or contaminated
							**Change:**No recommendation
							**Provide:**Eyewash, Quick drench
	First Aid
			(See procedures)**Eye:**Irrigate immediately
							**Skin:**Soap flush immediately
							**Breathing:**Respiratory support
							**Swallow:**Medical attention immediately
Respirator Recommendations
			**NIOSH****At concentrations above the NIOSH REL, or where there is no REL, at any detectable concentration:** (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 canisterAny appropriate escape-type, self-contained breathing apparatus
				Important additional information about respirator selection
See also
			INTRODUCTION
					  ICSC CARD: 0509

			
							

			Page last reviewed:  October 30, 2019						Content
							source: 	National Institute for Occupational Safety and Health NIOSH Pocket Guide to Chemical Hazards
Introduction
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CAS Numbers
RTECS Numbers
Appendices
A – NIOSH Potential Occupational Carcinogens
B – Thirteen OSHA-Regulated Carcinogens
C – Supplementary Exposure Limits
D – Substances with No Established RELs
E – OSHA Respirator Requirements for Selected Chemicals
F – Miscellaneous Notes
G – 1989 Air Contaminants Update Project: Exposure Limits NOT in Effect
Type C & CE – Definitions for Type C and Type CE Respirators
Personal Protection and Sanitation Codes
First Aid Procedures Follow NIOSH Facebook
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