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Chemical Datasheet

METHYL TERT-BUTYL ETHER

3 - Flammable liquid
Chemical Identifiers | Hazards | Response Recommendations | Physical Properties | Regulatory Information | Alternate Chemical Names

Chemical Identifiers

The Chemical Identifier fields include common identification numbers, the NFPA diamond U.S. Department of Transportation hazard labels, and a general description of the chemical. The information in CAMEO Chemicals comes from a variety of data sources.
CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 1634-04-4   (METHYL TERT-BUTYL ETHER)
  • Flammable Liquid
NIOSH Pocket Guide International Chem Safety Card
none
NFPA 704
data unavailable
General Description
A colorless liquid with a distinctive anesthetic-like odor. Vapors are heavier than air and narcotic (cause drowsiness when inhaled). This liquid has a flash point lower than most ambient temperatures, so it will readily ignite under most conditions. It is less dense than water and moderately soluble in water. Used as a octane booster in gasoline.

Hazards

The Hazard fields include special hazard alerts air and water reactions, fire hazards, health hazards, a reactivity profile, and details about reactive groups assignments and potentially incompatible absorbents. The information in CAMEO Chemicals comes from a variety of data sources.
Reactivity Alerts
Air & Water Reactions
Highly flammable. Oxidizes readily in air to form unstable peroxides that may explode spontaneously [Bretherick 1979. p.151-154, 164]. A mixture of liquid air and diethyl ether exploded spontaneously [MCA Case History 616. 1960].
Fire Hazard
Special Hazards of Combustion Products: May contain irritating and toxic gases.

Behavior in Fire: May be ignited by heat, sparks or flames. Containers may explode in heat of fire. Vapor explosion hazard indoors, outdoors, or in sewers. (USCG, 1999)
Health Hazard
INHALATION: May cause dizziness or suffocation. Contact may irritate or burn eyes or skin. May be harmful if swallowed. (USCG, 1999)
Reactivity Profile
Ethers, such as METHYL TERT-BUTYL ETHER, can act as bases. They form salts with strong acids and addition complexes with Lewis acids. The complex between diethyl ether and boron trifluoride is an example. Ethers may react violently with strong oxidizing agents. In other reactions, which typically involve the breaking of the carbon-oxygen bond, ethers are relatively inert.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

The Response Recommendation fields include isolation and evacuation distances, as well as recommendations for firefighting, non-fire response, protective clothing, and first aid. The information in CAMEO Chemicals comes from a variety of data sources.
Isolation and Evacuation
Excerpt from ERG Guide 127 [Flammable Liquids (Water-Miscible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet).

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)
Firefighting
Excerpt from ERG Guide 127 [Flammable Liquids (Water-Miscible)]:

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient. CAUTION: For fire involving UN1170, UN1987 or UN3475, alcohol-resistant foam should be used. CAUTION: Ethanol (UN1170) can burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.).

SMALL FIRE: Dry chemical, CO2, water spray or alcohol-resistant foam.

LARGE FIRE: Water spray, fog or alcohol-resistant foam. Avoid aiming straight or solid streams directly onto the product. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2024)
Non-Fire Response
Excerpt from ERG Guide 127 [Flammable Liquids (Water-Miscible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2024)
Protective Clothing
Wear goggles, self-contained breathing apparatus, rubber gloves, boots and overclothing. (USCG, 1999)
DuPont Tychem® Suit Fabrics
Tychem® Fabric Legend
QS = Tychem 2000 SFR
QC = Tychem 2000
SL = Tychem 4000
C3 = Tychem 5000
TF = Tychem 6000
TP = Tychem 6000 FR
RC = Tychem RESPONDER® CSM
TK = Tychem 10000
RF = Tychem 10000 FR
Testing Details
The fabric permeation data was generated for DuPont by a third party laboratory. Permeation data for industrial chemicals is obtained per ASTM F739. Normalized breakthrough times (the time at which the permeation rate exceeds 0.1 μg/cm2/min) are reported in minutes. All chemicals have been tested between approximately 20°C and 27°C unless otherwise stated. All chemicals have been tested at a concentration of greater than 95% unless otherwise stated.
Chemical warfare agents (Lewisite, Sarin, Soman, Sulfur Mustard, Tabun and VX Nerve Agent) have been tested at 22°C and 50% relative humidity per military standard MIL-STD-282. "Breakthrough time" for chemical warfare agents is defined as the time when the cumulative mass which permeated through the fabric exceeds the limit in MIL-STD-282 [either 1.25 or 4.0 μg/cm2].
A Caution from DuPont
This information is based upon technical data that DuPont believes to be reliable on the date issued. It is subject to revision as additional knowledge and experience are gained. The information reflects laboratory performance of fabrics, not complete garments, under controlled conditions. It is intended for informational use by persons having technical skill for evaluation under their specific end-use conditions, at their own discretion and risk. It is the user's responsibility to determine the level of toxicity and the proper personal protective equipment needed. Anyone intending to use this information should first verify that the garment selected is suitable for the intended use. In many cases, seams and closures have shorter breakthrough times and higher permeation rates than the fabric. If fabric becomes torn,abraded or punctured, or if seams or closures fail, or if attached gloves, visors, etc. are damaged, end user should discontinue use of garment to avoid potential exposure to chemical. Since conditions of use are outside our control, DuPont makes no warranties, express or implied, including, without limitation, no warranties of merchantability or fitness for a particular use and assume no liability in connection with any use of this information. This information is not intended as a license to operate under or a recommendation to infringe any patent, trademark or technical information of DuPont or others covering any material or its use.
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Methoxy 2-methylpropane, 2- 1634-04-4 Liquid >480 >480 >480 >480 >480 >480 >480
Methyl tert-butyl ether 1634-04-4 Liquid >480 >480 >480 >480 >480 >480 >480
> indicates greater than.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

...Tychem® ThermoPro, Tychem® Reflector® and Tychem® TK styles 600T/601T (with aluminized outer suit) garments are designed and tested to help reduce burn injury during escape from a flash fire. Users of Tychem® ThermoPro, Tychem® Reflector® and Tychem® TK styles 600T/601T (with aluminized outer suit) garments should not knowingly enter an explosive environment. Tychem® garments with attached socks must be worn inside protective outer footwear and are not suitable as outer footwear. These attached socks do not have adequate durability or slip resistance to be worn as the outer foot covering.

(DuPont, 2024)

First Aid
INHALATION: Move victim to fresh air; call emergency medical care. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.

EYES OR SKIN: Flush with running water for at least 15 minutes; hold eyelids open if necessary. Remove and isolate contaminated clothing and shoes at the site. Keep victim quiet and maintain normal body temperature.

INGESTION: If victim is unconscious or having convulsions, do nothing except keep victim warm. (USCG, 1999)

Physical Properties

The Physical Property fields include properties such as vapor pressure and boiling point, as well as explosive limits and toxic exposure thresholds The information in CAMEO Chemicals comes from a variety of data sources.

Note: For Vapor Density and Specific Gravity, comparing the value to 1.0 can tell you if the chemical will likely sink/rise in air or sink/float in fresh water (respectively). Short phrases have been added to those values below as an aid. However, make sure to also consider the circumstances of a release. The Vapor Density comparisons are only valid when the gas escaping is at the same temperature as the surrounding air itself. If the chemical is escaping from a container where it was pressurized or refrigerated, it may first escape and behave as a heavy gas and sink in the air (even if it has a Vapor Density value less than 1). Also, the Specific Gravity comparisons are for fresh water (density 1.0 g/mL). If your spill is in salt water (density about 1.027 g/mL), you need to adjust the point of comparison. There are some chemicals that will sink in fresh water and float in salt water.
Chemical Formula:
  • C5H12O
Flash Point: -14°F (USCG, 1999)
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: -164.2°F (USCG, 1999)
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 0.7405 at 68°F (USCG, 1999) - Less dense than water; will float
Boiling Point: 131.4°F at 760 mmHg (USCG, 1999)
Molecular Weight: 88.15 (USCG, 1999)
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

Interim AEGLs for Methyl-tertiary-butyl ether (MTBE) (1634-04-4)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 50 ppm 1400 ppm 13000 ppm 2-flame icon indicates value is 50-99% of LEL. Extreme safety consideration against explosions must be taken into account.
30 minutes 50 ppm 800 ppm 7500 ppm 1-flame icon indicates value is 10-49% of LEL. Safety consideration against explosions must be taken into account.
60 minutes 50 ppm 570 ppm 5300 ppm 1-flame icon indicates value is 10-49% of LEL. Safety consideration against explosions must be taken into account.
4 hours 50 ppm 400 ppm 2700 ppm 1-flame icon indicates value is 10-49% of LEL. Safety consideration against explosions must be taken into account.
8 hours 50 ppm 400 ppm 1900 ppm 1-flame icon indicates value is 10-49% of LEL. Safety consideration against explosions must be taken into account.
Lower Explosive Limit (LEL) = 16000
1-flame icon indicates value is 10-49% of LEL. Safety consideration against explosions must be taken into account.
2-flame icon indicates value is 50-99% of LEL. Extreme safety consideration against explosions must be taken into account.
(NAC/NRC, 2024)

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
Methyl tert-Butyl Ether (MTBE) (1634-04-4) 50 ppm star-in-circle icon indicates that odor should be detectable near ERPG-1. 1000 ppm 5000 ppm 1-flame icon indicates value is 10-49% of LEL. LEL = 16000 ppm
star-in-circle icon indicates that odor should be detectable near ERPG-1.
1-flame icon indicates value is 10-49% of LEL.
(AIHA, 2022)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Methyl tert-butyl ether; (MTBE) (1634-04-4) 50 ppm 570 ppm 5300 ppm 1-flame icon indicates value is 10-49% of LEL. LEL = 16000 ppm
1-flame icon indicates value is 10-49% of LEL.
(DOE, 2024)

Regulatory Information

The Regulatory Information fields include information from the U.S. Environmental Protection Agency's Title III Consolidated List of Lists, the U.S. Cybersecurity and Infrastructure Security Agency's Chemical Facility Anti-Terrorism Standards, and the U.S. Occupational Safety and Health Administration's Process Safety Management of Highly Hazardous Chemicals Standard List (see more about these data sources).

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Methyl tert-butyl ether 1634-04-4 1000 pounds 313

(EPA List of Lists, 2024)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names

This section provides a listing of alternate names for this chemical, including trade names and synonyms.