Skip directly to local search Skip directly to A to Z list Skip directly to navigation Skip directly to site content Skip directly to page options
CDC Home

Enter search terms separated by spaces.

Methylene bisphenyl isocyanate

Synonyms & Trade Names
4,4'-Diphenylmethane diisocyanate; MDI; Methylene bis(4-phenyl isocyanate); Methylene di-p-phenylene ester of isocyanic acid
CAS No.
101-68-8
RTECS No.
NQ9350000
DOT ID & Guide
Formula
CH2(C6H4NCO)2
Conversion
1 ppm = 10.24 mg/m3
IDLH
75 mg/m3
See: 101688
Exposure Limits
NIOSH REL
: TWA 0.05 mg/m3 (0.005 ppm) C 0.2 mg/m3 (0.020 ppm) [10-minute]
OSHA PEL
: C 0.2 mg/m3 (0.02 ppm)
Measurement Methods

NIOSH 5521 , 5522 , 5525;
OSHA 18
See: NMAM or OSHA Methods
Physical Description
White to light-yellow, odorless flakes. [Note: A liquid above 99°F.]
MW:
250.3
BP:
597°F
MLT: 99°F
Sol:
0.2%
VP(77°F): 0.000005 mmHg
IP:
?
Sp.Gr:
1.23 (Solid at 77°F) 1.19 (Liquid at 122°F)
Fl.P:
390°F
UEL:
?
LEL:
?
Combustible Solid
Incompatibilities & Reactivities
Strong alkalis, acids, alcohol [Note: Polymerizes at 450°F.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, nose, throat; resp sensitization; cough, pulmonary secretions, chest pain, dyspnea (breathing difficulty); asthma
Target Organs
Eyes, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet or contaminated
Change: Daily
First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Soap wash immediately
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations

NIOSH

Up to 0.5 mg/m3:
(APF = 10) Any supplied-air respirator*

Up to 1.25 mg/m3:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*

Up to 2.5 mg/m3:
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

Up to 75 mg/m3:
(APF = 2000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode

Emergency or planned entry into unknown concentrations or IDLH conditions:
(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 canister having an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also: INTRODUCTION   See ICSC CARD: 0298   See MEDICAL TESTS: 0147
 
Contact Us:
USA.gov: The U.S. Government's Official Web PortalDepartment of Health and Human Services
Centers for Disease Control and Prevention   1600 Clifton Road Atlanta, GA 30329-4027, USA
800-CDC-INFO (800-232-4636) TTY: (888) 232-6348 - Contact CDC–INFO