Material Safety Data Sheet (MSDS)

OSHA's Hazard Communication Standard (1983)-Worker's Right to Know and also Title III of Superfund Amendment and Reauthorization Act (SARA) , Emergency Planning and Community Right to Know (1986) require that MSDS be available for each chemical. OSHA does not set a specific format for MSDS, however the following must be included:

Hazardous ingredients

Physical and chemical characteristics (Boiling point, vapor pressure, etc.)

Potential for hazards such as fire, explosion, reaction

Possible health hazards and symptoms

Pathways into the body such as inhalation or skin exposure

Safe exposure limits and carcinogenic potential

The best way for a worker to find out whether a chemical is hazardous is to check the hazardous chemical list. If the name of the chemical appears on that list, it is hazardous, and an MSDS must be available for that chemical. The Hazard Communication Standard requires that the chemical's name be the same on the hazardous chemical list and on the MSDS to facilitate the worker's obtaining information about the hazardous chemical.

MSDS Organization

The MSDS should answer

o        What is the material and what do I need to know IMMEDIATELY in an emergency?

o        What should I do if a hazardous situation occurs?

o        How can I prevent hazardous situations from occurring?

o        Is there any other useful information about this material?

 

What is the material and what do I need to know IMMEDIATELY in an emergency?

1. Chemical Product and Company ID

2. Composition/Information on Ingredients

3. Hazards Identification.

 

What should I do if a hazardous situation occurs?

4. First Aid Measures

5. Fire-Fighting Measures

6. Accidental Release Measure.

 

How can I prevent hazardous situations from occurring?

7. Handling and Storage

8. Exposure Controls/Personal Protection

9. Physical and Chemical Properties

10. Stability and Reactivity

 

Is there any other useful information about this material?

11. Toxicological Information

12. Ecological Information

13. Disposal Considerations

14. Transport Information

15. Regulatory Information

16. Other Information

Click on the links below for more information on MSDS.

 

What is a MSDS?

MSDS according to OSHA Standard (USA only)

MSDS  ANSI-16 Part (USA and Canada only)

MSDS EU-16 Part (Europe/International)

 

MSDS Terminology

OSHA PEL (OSHA Permissible Exposure Level):

This is a time weighted average (TWA) over an 8-hour period and is expressed in (ppm) or (mgm/m3)

 OSHA PEL Limits

 

 

STEL (Short Term Exposure Level):

Maximum concentration exposed for up to 15 minutes without harm, while the daily TWA is not exceeded.

 

ACGIH TLV (American Congress of Governmental Industrial Hygienists Threshold Limit Value):

Chemical threshold limit value that is used to identify the airborne concentration of a material to which most persons can be exposed to on a daily basis without an adverse effect.

 

IDLH (Immediately Dangerous to Life and Health):

Usually refers to a concentration of a chemical measured in (ppm), (mg/m3) or (%) which will kill or impair a person exposed for 30 minutes or less.

TWA (Time Weighted Average)

 For exposures to a single chemical:

TWA =S  (xi ti ) / 8 = (x1 t1 + x2t2 + ..... +xntn) / 8

TWA value should be less than or equal to PEL. If TWA is greater than PEL it means overexposure.

where ,

xi = concentration of the chemical (ppm) or (mg/m3)

ti =exposure time (hr)

n=total number of concentrations at which chemical exposure occurs

Example:

In an eight-hour shift. an employee is exposed to the following concentrations of chemical A which has PEL = 400 ppm:

Duration of Exposure

(hr)

Amount of Exposure

(ppm)

4

250

1

380

2

425

1

450

 TWA =S  (xi ti ) / 8 = (x1 t1 + x2t2 + ..... +xntn) / 8 =

TWA = ( 250 x 4 + 380 x 1 + 425 x 2 + 450 x 1 )/8 = 335 ppm

TWA = 335 ppm < PEL=400 ppm

Since Time Weighted Exposure (TWA) is lower than PEL there is no overexposure.

 Additive Effects of Two or More Chemicals Exposed During 8-Hour Period

X = S Ci/(PEL)i = C1/(PEL) 1 + C2/(PEL)2 +.......+Cn/(PEL)n

where,

Ci = Concentration of each chemical (ppm) or (mg/m3)

(PEL)i = OSHA's permissible exposure level for each chemical

If X < 1.00 the mixture does not exceed the threshold value (TLV)

If X > 1.00 the mixture exceeds the TLV.

 

Example: During an eight-hour day an employee is exposed to the following mixture of substances. Does the mixture exceed the Threshold Value (TLV) ?

Chemical

Amount of Exposure

(ppm)

PEL

(ppm)

A

4

10

B

60

100

C

230

400

 

X = 4/10 + 60/100 + 230/400 = 1.575

Since X = 1.575 > 1.00 The mixture exceeds the threshold value.

 

Reactivity Data:

A "reactive" chemical has a tendency to undergo a chemical change and release energy. These chemical changes may cause:

o        Pressure buildup

o        Temperature increase

o        Formation of toxic or corrosive byproducts

 

Stability:

An unstable chemical can undergo changes that cause :

Pressure

Heat

Hazardous decay

Conditions to avoid: If the product is unstable, the following are the most common conditions to avoid:

Heat

Flame

Sparks

Sunlight

Pressure

Vibration

Incompatibility:

This part of MSDS lists the chemical or materials that must be kept away from the reactive chemical

 

Hazardous Decomposition or Byproducts:

Sometimes when a reactive chemical reacts, it decays and can break down into more hazardous materials such as carbon monoxide, chlorine, etc. Sometimes the byproduct can be fire, heat or explosion.

 

Hazardous Polymerization:

A reactive chemical may combine with another chemical to form "long-chain" molecules. The resulting chemical releases a significant amount of heat which usually causes fire.

 

Boiling Point:

Temperature at which a liquid changes to vapor.

 

Vapor Pressure:

Pressure that a liquid' s vapor exerts on the air. The higher the pressure, the more easily the liquid will evaporate.

 

Vapor Density:

Relative weight of a chemical's vapor to the weight of an equal volume of air.

If the vapor density of a chemical is greater than 1.00, chemical's vapor is heavier than air (the chemical sinks).

If vapor density is less than 1.00, chemical's vapor is lighter than air and it will rise.

 

Specific Gravity:

The weight of a chemical in relation to the weight of an equal volume of water.

If specific gravity greater than 1.00, the chemical is heavier than water and it will sink.

If specific gravity of a chemical is less than 1.00, the chemical is lighter than water and it will float.

 

LFL (Lower Flammable Level):

The lowest concentration of a chemical which will burn if an ignition source is present.

 

UFL (Upper Flammable Level):

The highest concentration of a chemical which will burn if an ignition source is present.

 

 Flash Point:

The temperature at which a liquid will give off enough flammable vapor to ignite.

 

CAS Number:

Chemical abstract number. A unique number assigned to a chemical to identify it.

 

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Last Update: January 9, 2007

By: Serdar Z. Elgun