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MSDS for MAGNESIUM OXIDE Page 1

1 - PRODUCT IDENTIFICATION

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PRODUCT NAME: MAGNESIUM OXIDE

FORMULA: MGO

FORMULA WT: 40.30

CAS NO.: 1309-48-4

NIOSH/RTECS NO.: OM3850000

PRODUCT CODES: 2477,2484,2476,2480

EFFECTIVE: 09/03/86

REVISION #02

PRECAUTIONARY LABELLING

BAKER SAF-T-DATA(TM) SYSTEM

HEALTH - 1 SLIGHT

FLAMMABILITY - 0 NONE

REACTIVITY - 1 SLIGHT

CONTACT - 1 SLIGHT

HAZARD RATINGS ARE 0 TO 4 (0 = NO HAZARD; 4 = EXTREME HAZARD).

LABORATORY PROTECTIVE EQUIPMENT

SAFETY GLASSES; LAB COAT

PRECAUTIONARY LABEL STATEMENTS

WARNING

MAY CAUSE IRRITATION

MAY BE HARMFUL IF INHALED

DURING USE AVOID CONTACT WITH EYES, SKIN, CLOTHING. WASH THOROUGHLY AFTER

HANDLING. WHEN NOT IN USE KEEP IN TIGHTLY CLOSED CONTAINER.

SAF-T-DATA(TM) STORAGE COLOR CODE: ORANGE (GENERAL STORAGE)

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2 - HAZARDOUS COMPONENTS

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COMPONENT % CAS NO.

MAGNESIUM OXIDE 90-100 1309-48-4

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3 - PHYSICAL DATA

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BOILING POINT: 3600 C ( 6512 F) VAPOR PRESSURE(MM HG): N/A

MELTING POINT: 2800 C ( 5072 F) VAPOR DENSITY(AIR=1): N/A

SPECIFIC GRAVITY: 3.60 EVAPORATION RATE: N/A

(H2O=1) (BUTYL ACETATE=1)

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MSDS for MAGNESIUM OXIDE Page 2

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SOLUBILITY(H2O): NEGLIGIBLE (LESS THAN 0.1 %) % VOLATILES BY VOLUME: 0

APPEARANCE & ODOR: WHITE TO LIGHT-GRAY POWDER.

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4 - FIRE AND EXPLOSION HAZARD DATA

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FLASH POINT (CLOSED CUP N/A

FLAMMABLE LIMITS: UPPER - N/A % LOWER - N/A %

FIRE EXTINGUISHING MEDIA

USE EXTINGUISHING MEDIA APPROPRIATE FOR SURROUNDING FIRE.

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5 - HEALTH HAZARD DATA

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THRESHOLD LIMIT VALUE (TLV/TWA): 10 MG/M3 ( PPM)

PERMISSIBLE EXPOSURE LIMIT (PEL): 15 MG/M3 ( PPM)

CARCINOGENICITY: NTP: NO IARC: NO Z LIST: NO OSHA REG: NO

EFFECTS OF OVEREXPOSURE

DUST INHALATION MAY CAUSE TIGHTNESS AND PAIN IN CHEST, COUGHING, AND

DIFFICULTY IN BREATHING.

INHALATION OF FUMES MAY RESULT IN LEUKOCYTOSIS.

CONTACT CAN CAUSE EYE IRRITATION.

TARGET ORGANS

RESPIRATORY SYSTEM, EYES

MEDICAL CONDITIONS GENERALLY AGGRAVATED BY EXPOSURE

NONE IDENTIFIED

ROUTES OF ENTRY

INHALATION, EYE CONTACT, SKIN CONTACT

EMERGENCY AND FIRST AID PROCEDURES

INGESTION: IF SWALLOWED AND THE PERSON IS CONSCIOUS, IMMEDIATELY GIVE

LARGE AMOUNTS OF WATER. GET MEDICAL ATTENTION.

INHALATION: IF A PERSON BREATHES IN LARGE AMOUNTS, MOVE THE EXPOSED

PERSON TO FRESH AIR. GET MEDICAL ATTENTION.

EYE CONTACT: IMMEDIATELY FLUSH WITH PLENTY OF WATER FOR AT LEAST 15

MINUTES. GET MEDICAL ATTENTION.

SKIN CONTACT: IMMEDIATELY WASH WITH PLENTY OF SOAP AND WATER FOR AT LEAST

15 MINUTES.

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6 - REACTIVITY DATA

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MSDS for MAGNESIUM OXIDE Page 3

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STABILITY: STABLE HAZARDOUS POLYMERIZATION: WILL NOT OCCUR

CONDITIONS TO AVOID: AIR

INCOMPATIBLES: BROMINE TRIFLUORIDE AND TRICHLORIDE,

PHOSPHORUS PENTACHLORIDE

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7 - SPILL AND DISPOSAL PROCEDURES

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STEPS TO BE TAKEN IN THE EVENT OF A SPILL OR DISCHARGE

WEAR SUITABLE PROTECTIVE CLOTHING. CAREFULLY SWEEP UP AND REMOVE.

DISPOSAL PROCEDURE

DISPOSE IN ACCORDANCE WITH ALL APPLICABLE FEDERAL, STATE, AND LOCAL

ENVIRONMENTAL REGULATIONS.

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8 - PROTECTIVE EQUIPMENT

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VENTILATION: USE GENERAL OR LOCAL EXHAUST VENTILATION TO MEET

TLV REQUIREMENTS.

RESPIRATORY PROTECTION: RESPIRATORY PROTECTION REQUIRED IF AIRBORNE

CONCENTRATION EXCEEDS TLV. AT CONCENTRATIONS UP

TO 45 PPM, A HIGH-EFFICIENCY PARTICULATE

RESPIRATOR IS RECOMMENDED. ABOVE THIS LEVEL, A

SELF-CONTAINED BREATHING APPARATUS IS ADVISED.

EYE/SKIN PROTECTION: SAFETY GLASSES WITH SIDESHIELDS, NEOPRENE GLOVES

ARE RECOMMENDED.

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9 - STORAGE AND HANDLING PRECAUTIONS

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SAF-T-DATA(TM) STORAGE COLOR CODE: ORANGE (GENERAL STORAGE)

SPECIAL PRECAUTIONS

KEEP CONTAINER TIGHTLY CLOSED. SUITABLE FOR ANY GENERAL CHEMICAL STORAGE

AREA.

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10 - TRANSPORTATION DATA AND ADDITIONAL INFORMATION

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DOMESTIC (D.O.T.)

PROPER SHIPPING NAME CHEMICALS, N.O.S. (NON-REGULATED)

INTERNATIONAL (I.M.O.)

PROPER SHIPPING NAME CHEMICALS, N.O.S. (NON-REGULATED)