Ethyl methyl ketone peroxide

CAS 1338-23-4 C₈H₁₆O₄ MW 176.2000 Danger NIOSH data available

Exploding Bomb

Flame

Corrosion

Skull and Crossbones

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Health Hazard

Emergency: 911 | Poison Control: 1-800-222-1222

Recommended safety equipment

Personal protective equipment commonly recommended for the hazard classes shown above.

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Hazard Statements

Code	Statement	Hazard Class
`H227`	Combustible liquid	Flammable liquids
`H241`	Heating may cause a fire or explosion	Self-reactive substances and mixtures; Organic peroxides
`H302`	Harmful if swallowed	Acute toxicity, oral
`H315`	Causes skin irritation	Skin corrosion/irritation
`H318`	Causes serious eye damage	Serious eye damage/eye irritation
`H330`	Fatal if inhaled	Acute toxicity, inhalation
`H335`	May cause respiratory irritation	Specific target organ toxicity, single exposure; Respiratory tract irritation
`H336`	May cause drowsiness or dizziness	Specific target organ toxicity, single exposure; Narcotic effects
`H370`	Causes damage to organs	Specific target organ toxicity, single exposure
`H401`	Toxic to aquatic life	Hazardous to the aquatic environment, acute hazard

Precautionary Statements

Code	Statement
`P210`	Keep away from heat, hot surface, sparks, open flames and other ignition sources. No smoking.
`P234`	Keep only in original container.
`P235`	Keep cool.
`P240`	Ground/bond container and receiving equipment.
`P260`	Do not breathe dust/fume/gas/mist/vapors/spray.
`P261`	Avoid breathing dust/fume/gas/mist/vapors/spray.
`P264`	Wash hands [and ...] thoroughly after handling.
`P264+P265`	Wash hands [and ...] thoroughly after handling. Do not touch eyes.
`P270`	Do not eat, drink or smoke when using this product.
`P271`	Use only outdoors or in a well-ventilated area.
`P273`	Avoid release to the environment.
`P280`	Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/...
`P284`	[In case of inadequate ventilation] Wear respiratory protection.
`P301+P317`	IF SWALLOWED: Get medical help.
`P302+P352`	IF ON SKIN: wash with plenty of water/...
`P304+P340`	IF INHALED: Remove person to fresh air and keep comfortable for breathing.
`P305+P354+P338`	IF IN EYES: Immediately rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing.
`P308+P316`	IF exposed or concerned: Get emergency medical help immediately.
`P316`	Get emergency medical help immediately.
`P317`	Get emergency medical help.
`P319`	Get medical help if you feel unwell.
`P320`	Specific treatment is urgent (see ... on this label).
`P321`	Specific treatment (see information on this label and safety datasheet)).
`P330`	Rinse mouth.
`P332+P317`	If skin irritation occurs: Get medical help.
`P362+P364`	Take off contaminated clothing and wash it before reuse.
`P370+P378`	In case of fire: Use ... to extinguish.
`P370+P380+P375`	In case of fire: Evacuate area. Fight fire remotely due to the risk of explosion.
`P378`	Use ... to extinguish.
`P403`	Store in a well-ventilated place.
`P403+P233`	Store in a well-ventilated place. Keep container tightly closed.
`P405`	Store locked up.
`P410`	Protect from sunlight.
`P411`	Store at temperatures not exceeding ... °C/...°F.
`P420`	Store separately.
`P501`	Dispose of contents/container to ...

Exposure Limits

NIOSH REL	Ceiling: 0.2 ppm
Skin Notation	Yes — can be absorbed through skin

Physical Properties

Colorless liquid with a characteristic odor.

Boiling Point	244°F (decomposes)
Flash Point	125-200°F for 60% MEKP (open cup)
Specific Gravity	1.12

NFPA 704 Diamond

Synonyms

2-butanone peroxide, MEKP, MEK peroxide

Data Sources

GHS Classification: PubChem CID 3672772
NIOSH REL/IDLH: NIOSH Pocket Guide

Disclaimer: This information is compiled from public regulatory databases for reference only. It does not replace the manufacturer's Safety Data Sheet (SDS). Always consult the official SDS for your specific product before handling chemicals.

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