Dimethyl hydrogen phosphite

  • Dimethoxyphosphine oxide
  • Dimethylacid phosphite
  • Dimethylhydrogenphosphite
  • Dimethyl phosphite
  • Dimethyl phosphonate
  • DMHP
Formula
C2H7O3P
Structure
Description
Colorless liquid.
Uses
Lubricant additives, intermediate, adhesive.

Registry Numbers and Inventories.
CAS
868-85-9
EC (EINECS/ELINCS)
212-783-8
R 36/37/38 40
S 26 36/37/39
RTECS
SZ7710000
RTECS class
Tumorigen; Mutagen; Primary Irritant
UN (DOT)
1993
Beilstein/Gmelin
605574
Canada DSL/NDSL
NDSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C2H7O3P
Formula mass
110.04
Boiling point, °C
170.5
Vapor density (air=1)
3.80
Density
1.20 g/cm3 (20 C)
Solubility in water
soluble
Refractive index
1.4036 (20 C)

Hazards and Protection.
Storage
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Flammables-area. Store protected from moisture.
Handling
Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Avoid contact with eyes, skin, and clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep container tightly closed. Avoid contact with heat, sparks and flame. Avoid ingestion and inhalation. Do not allow contact with water. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames. Keep from contact with moist air and steam.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.
Small spills/leaks
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. Do not get water inside containers. A vapor suppressing foam may be used to reduce vapors.
Stability
Stable at room temperature in closed containers under normal storage and handling conditions.
Incompatibilities
Moisture, acid chlorides, strong acids, strong bases, strong oxidizing agents.
Decomposition
Phosphine, carbon monoxide, oxides of phosphorus, irritating and toxic fumes and gases, carbon dioxide.

Fire.
Flash Point,°C
29
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Will burn if involved in a fire. Use water spray to keep fire-exposed containers cool. Containers may explode in the heat of a fire. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT get water inside containers. Do NOT use straight streams of water.
Fire potential
HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
Hazards
Emits toxic fumes under fire conditions.
Combustion products
Emits toxic fumes under fire conditions.
Health
2
 
Flammability
3
 
 
Reactivity
0
 

Health.
Exposure effects
Effects may be delayed.
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea. Ingestion of large amounts may cause CNS depression.
   Inhalation
Causes respiratory tract irritation. Aspiration may lead to pulmonary edema. Vapors may cause dizziness or suffocation. Can produce delayed pulmonary edema. May cause burning sensation in the chest.
   Skin
Causes skin irritation. May cause irritation and dermatitis. May cause cyanosis of the extremities.
   Eyes
Causes eye irritation. May cause chemical conjunctivitis and corneal damage.

First aid
 
   Ingestion
Get medical aid. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
   Skin
Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.
UN number
1993
Response guide
Hazard class
3
Packing Group
I; II; III
 
USCG CHRIS Code
DPI
 
IMO Chemical Code
17
IMO Pollution Category
B
IMO Hazard code
S/P