METHYLACETYLENE AND PROPADIENE MIXTURE, STABILIZED

Methylacetylene-propadiene stabilized is a colorless gas with an acetylene like odor. It is shipped as a liquefied gas under its vapor pressure. Contact with the liquid can cause frostbite. It is easily ignited. The vapors are heavier than air. Any leak can either be liquid or vapor. It can asphyxiate by the displacement of air. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket.

• Highly Flammable
• Polymerizable

Highly flammable.

Behavior in Fire: Containers may explode. (USCG, 1999)

Simple asphyxiant. Toxicology of propadiene component not fully established. Contact with liquid may burn eyes and cause frostbite of skin. (USCG, 1999)

METHYLACETYLENE AND PROPADIENE MIXTURE presents a dangerous fire and explosion hazard when exposed to heat, flame or sparks or strong oxidizing agents. The liquid material in cylinders contains about 30% propadiene. Detonation may occur at 95°C [MCA Case History No. 632]. Reacts vigorously with strong oxidizing agents. Reaction with silver nitrate forms an acetylide igniting at 150°C [Grignard, 1935, vol. 3, p. 175]. Violent explosions occurring at low temperatures in ammonia synthesis equipment have been traced to the addition products of dienes and oxides of nitrogen produced from the interaction of nitrogen oxide and oxygen. [Bretherick, 1995].

• Hydrocarbons, Aliphatic Unsaturated
• Alkynes, with Acetylenic Hydrogen

Use caution: Liquids with this reactive group classification have been known to react with the absorbent listed below.

• Dirt/Earth

Excerpt from 116 [Gases - Flammable (Unstable); polymerization hazard]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 100 meters (330 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 800 meters (1/2 mile).

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 1600 meters (1 mile) in all directions; also, consider initial evacuation for 1600 meters (1 mile) in all directions. (ERG, 2020)

Excerpt from 116 [Gases - Flammable (Unstable); polymerization hazard]:

DO NOT EXTINGUISH A LEAKING GAS FIRE UNLESS LEAK CAN BE STOPPED.

SMALL FIRE: Dry chemical or CO2.

LARGE FIRE: Water spray or fog. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING 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. Do not direct water at source of leak or safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)

Excerpt from 116 [Gases - Flammable (Unstable); polymerization hazard]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Stop leak if you can do it without risk. Do not touch or walk through spilled material. Do not direct water at spill or source of leak. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. If possible, turn leaking containers so that gas escapes rather than liquid. Prevent entry into waterways, sewers, basements or confined areas. Isolate area until gas has dispersed. (ERG, 2020)

Excerpt from NIOSH Pocket Guide for Methyl acetylene-propadiene mixture:

Skin: FROSTBITE - Compressed gases may create low temperatures when they expand rapidly. Leaks and uses that allow rapid expansion may cause a frostbite hazard. Wear appropriate personal protective clothing to prevent the skin from becoming frozen.

Eyes: FROSTBITE - Wear appropriate eye protection to prevent eye contact with the liquid that could result in burns or tissue damage from frostbite.

Wash skin: No recommendation is made specifying the need for washing the substance from the skin (either immediately or at the end of the work shift).

Remove: WHEN WET (FLAMMABLE) - Work clothing that becomes wet should be immediately removed due to its flammability hazard (i.e., for liquids with a flash point <100°F).

Change: No recommendation is made specifying the need for the worker to change clothing after the workshift.

Provide: FROSTBITE WASH - Quick drench facilities and/or eyewash fountains should be provided within the immediate work area for emergency use where there is any possibility of exposure to liquids that are extremely cold or rapidly evaporating. (NIOSH, 2023)

No information available.

Excerpt from NIOSH Pocket Guide for Methyl acetylene-propadiene mixture:

Eye: FROSTBITE - If eye tissue is frozen, seek medical attention immediately; if tissue is not frozen, immediately and thoroughly flush the eyes with large amounts of water for at least 15 minutes, occasionally lifting the lower and upper eyelids. If irritation, pain, swelling, lacrimation, or photophobia persist, get medical attention as soon as possible.

Skin: FROSTBITE - If frostbite has occurred, seek medical attention immediately; do NOT rub the affected areas or flush them with water. In order to prevent further tissue damage, do NOT attempt to remove frozen clothing from frostbitten areas. If frostbite has NOT occurred, immediately and thoroughly wash contaminated skin with soap and water.

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible. (NIOSH, 2023)

• ALLENE-METHYLACETYLENE MIXTURE
• MAPP GAS
• MAPPGAS
• METHYL ACETYLENE, PROPADIENE MIXTURE
• METHYL ACETYLENE-ALLENE MIXTURE
• METHYL ACETYLENE-PROPADIENE MIXTURE
• METHYL ACETYLENE-PROPADIENE MIXTURE (STABILIZED)
• METHYLACETYLENE AND PROPADIENE MIXTURE, STABILIZED
• METHYLACETYLENE-ALLENE MIXTURE
• METHYLACETYLENE-PROPADIENE, [STABILIZED]
• PROPADIENE AND METHYLACETYLENE MIXTURE, STABILIZED
• PROPADIENE-METHYL ACETYLENE
• PROPADIENE-METHYLACETYLENE MIXTURE
• PROPYNE-ALLENE MIXTURE
• PROPYNE-PROPADIENE MIXTURE