1. Handling Chemicals Safely
Unit 00 Lab Safety Notes
Handling Chemicals Safely
12/22/2017
Work with only small containers
Use containers that can be easily handled.
Example:
What would you do if you had a big jug of a solution of potassium nitrate and you needed to pour it into a 10 mL graduated cylinder?

2. Handling Chemicals Safely
2. Mix chemicals only when instructed to do so by the teacher or by the directions.
Mixing chemicals in the wrong order or mixing the wrong chemicals together could result in dangerous reactions.
Pouring water into concentrated sulfuric or phosphoric acid releases a large amount of heat quickly - could boil the acid and cause it splatter or even be ejected from the container (AA - add acid to water)
Adding acid to ammonium thiocyanate releases highly toxic cyanide gas.

3. Handling Chemicals Safely
3. Read and reread labels
Look for:
Name
Concentration
Safety warnings

4. Aside Most chemicals we use are in solution.
They are solutions (mixtures) of the chemical and water.
M stands for molar and is used with the concentration measurement molarity.
% = percent

5. Handling Chemicals Safely
3. Read and reread labels
Name of chemical
- some chemicals have similar names so watch out (sodium sulfate, sodium sulfite, sodium sulfide)
Concentration
18M NaCl, 12M NaCl, 6M NaCl, 1M NaCl etc. . .
In this example
18M (18 molar) is the most concentrated (more NaCl, less water)
1M (1 molar) is the least concentrated (less NaCl, more water)

6. Handling Chemicals Safely
3. Read and reread labels cont’
Concentration
70% isopropyl alcohol, 90% isopropyl alcohol (usually percentage by mass)
70% isopropyl alcohol is 70 g of isopropyl alcohol mixed with 30g of water
90% isopropyl alcohol is 90 g of isopropyl alcohol for every 10 g of water
Important concept: the higher the number  the higher the concentration (less water)

7. Handling Chemicals Safely
3. Read and reread labels cont’
Safety Warnings
Corrosive - eat away skin, metals.
Poison/toxic
Carcinogenic - cancer causing
Oxidizer - starts fires easily or may react violently with other chemicals (provides oxygen)
Mutagen - causes mutations in DNA (genetic code)
Teratogen - causes mutations or birth defects in a developing fetus.

8. Handling Chemicals Safely
3. Read and reread labels cont’
Safety Warnings
Flammable - burns
Inflammable - burns
Volatile - evaporates easily
Explosive - could explode under certain circumstances.
Shock sensitive - bump, jar, etc… could cause explosive.
Hygroscopic - absorbs water from the air.

9. Handling Chemicals Safely
4. Read instructions all the way through first. (before you start the lab)
5. Replace caps, lids, and stoppers in bottles immediately when finished using that bottle.
Prevents spilling.
Prevents contamination of the bottle (dust, dirt, flies, etc…)
Prevents evaporation of water and volatile liquids. (changes the concentration and it may produce dangerous conditions in the lab)

10. Handling Chemicals Safely
6. Keep chemicals away from your face.
Never touch, taste, or smell a chemical directly.
(The proper way to smell a chemical is to waft it.)
Some vapors can cause immediate damage to eyes, mucous membranes, and lining of the lungs.
Damage to the lining of the lungs results in an outpouring of fluids (body is trying to wash away the cause of the damage) which in some cases results in death. (Hint: If you were performing an autopsy on someone, you would find a lot of fluid in the lungs.)

11. Handling Chemicals Safely
7. Work with flammable or toxic volatile chemicals under the fume hood.
Only dispense concentrated acids, ammonium hydroxide, flammable liquids, and toxic chemicals in a fume hood.
8. Keep chemicals as pure and uncontaminated as possible.
Never pour any back into a bottle.
Put the lids back on.
Ensure glassware is clean before you use it. (Could cause a dangerous reaction)

12. Handling Chemicals Safely
9. Use a pipette filler to fill a pipette with chemicals, never pipette by mouth.
10. Notify your teacher of spills.
The teacher may give you directions on how to clean it up.
Some spills may require evacuation of the room: Concentrated acids, concentrated ammonium hydroxide, mercury etc…

13. How to Use a Pipette. A = aspirate (remove air from bulb)
S = suction (draw liquid up into the pipet)
E = evacuate (drain liquid out of the pipet)
Always fill the pipet to zero. Move the pipet to the container you are using. Make sure the level is still at zero then drain out the amount you that you need. The markings on the pipet measure how much has drained out of the pipet.
The size of the pipet and graduations are mark on the pipet. (10 ml in 1/10 means it can deliver a maximum of 10 ml and each mark is 0.1 mL. When measuring you also read one decimal lower than the smallest graduation. Therefore on this pipet we would measure to the nearest .01mL.)

14. Handling Chemicals Safely
11. Put waste in the proper container.
Some chemical waste can be thrown in the regular trash.
Some require special disposal and will disposed of in a specific bottle labeled to receive that waste.
Unless directed otherwise, paper towels that have come in contact with chemicals must be rinsed with water before being thrown in the trash.

15. Handling Chemicals Safely
12. Clean up when finished.
Wipe down the lab table with a wet paper towel.
Wash all glassware with soap and water; then rinse with tap water and rinse with distilled water.

16. Bunsen Burner and Glassware Safety
1. Never use a Bunsen burner to heat flammable liquids.
2. Check gas hose for cracks
3. Make sure the hose fits securely on the gas valve and Bunsen burner fittings.
4. Stand back from the burner while lighting it.
5. Use a striker to light the burner. If not available, always strike the match away from you.
6. Light the match first, then turn on the gas.

17. Bunsen Burner and Glassware Safety
7. Turn the gas off immediately if the flame sputters, flares, or goes out, or if you smell gas.
8. Check glassware for stars, chips, cracks, etc…glass with fracture may break when heat or put under pressure.
9. Clamp narrow-necked containers to the ring stand.
10. Move test tubes back and forth through the flame at an angle while heating. (Point the opening away from people)

18. Bunsen Burner and Glassware Safety
11. Don’t heat closed containers. (It’s a bomb.)
12. Hold hot glassware in beaker tongs or hot mitts.

19. Bunsen Burner Safety
What do you have to worry about if you are using flammable chemicals at home or work?
Electrical equipment: In a room with normal ventilation: plugging or unplugging an electrical cord, turning on a light switch, or a motor running (fan, refrigerator compressor, air conditioner, etc..) will produce enough spark to cause an explosion.
Pilot lights: most things that run on natural gas, have a pilot light (small flame that’s always on)
Smoking/open flames

20. Thermometer Safety.. Prevent Thermometers from breaking by:
Don’t shake them down - could hit them on something
Don’t overheat them -
(Even the metal thermometers) Don’t put in flames (only the wire of a thermocouples can be put in a flame)
Don’t allow the thermometer to touch the bottom of the glassware when heating.
Preventing them from rolling off the tables.

21. Thermometer Safety.. If a thermometer breaks, Tell the teacher,
If it is a mercury thermometer, we will evacuate the room and the teacher will have to clean it up. (Mercury gives off vapors which can pass through the skin or be breathed in; Mercury is poisonous.)

22. Glass Tubing Safety..
When inserting glass tubing into a rubber stopper,
Use leather gloves to protect your hands,
Use water or glycerin to lubricate the tubing.
Twist the stopper if any resistance

23. Centrifuge Safety.. A centrifuge spins at a very high rate of speed.
Never run a centrifuge with an unbalanced load.
Never run a centrifuge faster then the directions or the instructor tells you to. The basket, the thing that holds the test tubes, is only rated up to a certain speed. If you over speed the basket it could come apart. (bomb)

24. Dressing for safety.. Don’t wear loose or baggy clothing
Could knock over something,
Catch fire
Could drag it through chemicals
Wear long pants/skirts to protect the legs
Wear long sleeves to protect the arms.
Closed toed shoes to protect the feet
2, 3, & 4 to protect from spills and flying glass.
Avoid synthetic materials that burn easily and that melt and stick to the skin (nylon, polyester, rayon, etc…) (use natural: cotton, wool)

25. Dressing for safety..
6. Tie up long hair: hair that is not tied up could fall into a flame, chemicals.
7. Remove rings and watches: corrosive chemicals could get trapped between the jewelry and the skin.

26. Dressing for safety..
8. Take out contact lenses: If a chemical gets in your eye,
Lenses trap the chemical against your eye
Lenses prevent the chemical from being washed away.
Pain of the chemical will cause your eyelids to clamp shut
Someone will have to hold your eyes open to remove the contacts.
You have literally seconds to prevent permanent eye damage or blindness
Gas permeable lenses trap toxic/corrosive vapors next to your eye (contact lens demo)

27. Dressing for safety.. 9. Cover your eyes with splash proof goggles.
10. Protect your hands with the right kind of gloves.
Rubber (thick) - protects from corrosive chemicals (concentrated acids and bases)
Rubber - protects from chemicals (short term protection from acids/bases/solvents. IOW: if you get acetone on them, the acetone will slowly go through the gloves)
Leather - protects from cuts from broken glass and sharp metal.
Thermal - (hot mitts) protects from burns from extreme heat or cold.

28. Behavior in the lab..
Have a healthy respect for the lab - accidents can and do happen!!!
1. Be mature - No horseplay in the lab ever!!!
2. Be safety minded - look for safety problems and fix them (keep aisles clear, move flammable material away before lighting the bunsen burner, etc…)
3. No eating, drinking, or applying makeup in the lab.

29. Emergency Equipment.. 1. Cuts
Small cuts - wash to remove any chemicals then put on a bandage.
Large cuts - apply constant direct pressure to the wound.
2. Burns - rinse in cold water for at least 5 minutes.

30. Emergency Equipment.. 3. Chemical in the eyes:
Rinse with eye wash for at least 15 min
Eye should be held open by the injured student or classmate.
Eyes should be continuously rolled left, right, up and down
If wearing contact lenses remove them as soon as possible.
Get immediate medical attention

31. Emergency Equipment.. 4. Chemical on the skin
Small amount on bare skin - wash off with plenty of water in the sink.
Large spills of corrosive chemicals - safety shower - remove clothing - rinse for 15 min
5. Lab fire -
Small fire - cover/smother
Fire extinguisher - aim at the base of the fire
Too big to control - 88 and out the gate
6. Clothing fire
Stop, drop, and roll - smother with fire blanket - immediate medical attention

32. Types of Fires. Class A (alpha):
wood, paper, trash, general combustibles; can be put out with any type of extinguisher.
Class B (bravo):
flammable liquids, petroleum products; gasoline, oil, tar;
No water: petroleum products float on water.
Put out with foam, CO2, or powder extinguishers. B

33. Types of Fires. Class C (charley): electrical fires No water
Use powder or CO2 extinguishers
Danger of electrocution
4. Class D (delta):
Special fires
Combustible metals C D

34. OSHA Symbols

35. OSHA Symbols

36. OSHA Symbols

37. Aside. Flash point is a term describing how flammable a liquid is.
The lower the flash point the more flammable it is. (key concept)
Flash Point: the lowest temperature above which a volatile solid or liquid will produce enough vapor that will ignite when exposed to a brief flame.
IOW: above the flash point, there is enough vapor to catch fire.

38. NFPA. National Fire Protection Association
Chemical labeling system showing the hazards of a chemical.
It is usually represented by a diamond, separated into 4 diamonds.
Each of the smaller diamonds has a code from 0 to 4 representing the immediate danger of the substance. (0 = no threat) (4=great threat)
Health (left, blue) = how poisonous is it.
Flammability (top, red) = how flammable it is
Reactivity (right, yellow) = how likely to explode, react violently, or decompose under heat.

39. NFPA. National Fire Protection Association
Special (specific hazards) (bottom/white): gives the specific hazard for this chemical
ACID - acid (such as hydrochloric acid, HCl)
ALK - alkali (base such as NaOH, sodium hydroxide)
OXY - oxidizer
W - no water (chemical reacts with water)

40. NFPA. National Fire Protection Association

41. SDS Safety Data Sheet Every product in the United States has a SDS.
(From potassium cyanide to 409 spray cleaner)
An SDS lists the safety data for a particular substance.
When you buy a product from a store you can request a copy of the SDS.
Most businesses are required to keep a copy of the SDS for each chemical that they use.
They are also required to have it available for employees to look at.
An SDS is divided into 16 sections.

42. SDS Safety Data Sheet Section 1: Chemical product
Name the chemical is sold under.
Manufacturer
Section 2: Composition, information on ingredients.
Lists all the chemicals present and how much.
For each chemical it may list the synonym or other names that it goes by.
Pure substances: one chemical listed.
Mixtures: more that one chemical listed.

43. SDS Safety Data Sheet Section 3: Hazards identification
Physical description
Hazards overview
Section 4: First Aid Measures
What to do for inhalation, eye contact, external contact (skin), and internal contact (swallowing)
Section 5: Fire fighting measures
NFPA code
Special procedures if substance is involved in a fire

44. SDS Safety Data Sheet Section 6: Accidental Release Measures
What do you do if you spill it
Section 7: Handling and Storage
how to store and dispense it
Section 8: Exposure controls, personal protection
What type of exposure to avoid
Personal protection equipment to be used.

45. SDS Safety Data Sheet Section 9: Physical and chemical properties
Physical description
Solubility: What will it dissolve in
Chemical formula
Formula weight
Specific gravity or density
Melting point/ boiling point
Vapor pressure
Vapor density

46. SDS Safety Data Sheet Section 10: Stability and reactivity
Situations or substances to avoid
Situations that cause it to decompose.
Section 11: Toxicological information.
How poisonous it is
Acute = short term effects
Chronic = long term effects
LD50 (lethal dose 50%): dose per kilogram of body weight required to kill 50% of a test animal population.

47. SDS Material Safety Data Sheet
Section 12: Ecological Information
Impact it could have on the environment
Section 13: Disposal considerations
How to dispose of the substance.
Section 14: Transport Information
Section 15: Regulatory information
Section 16: Other information.