Safety precautions, Dos and Donts in Labs

1. Laboratory Safety
for Chemistry students

2. The Four Principles of Safety
• The safety procedures in a chemistry laboratory can be summarized as RAMP.
• Recognize, Assess, Minimize, and Prepare.

3. Basic Safety Rules for Laboratories Handling Chemicals
1. Follow instructor and laboratory instructions carefully.
2. Wear proper eye protection.
3. Wear clothing that protects against exposure and provides protection
from spills. Wear chemically resistant gloves when needed.
4. Do not eat, drink, smoke or use smokeless tobacco products, chew
gum, apply cosmetics, or take medications in the laboratory.
5. Use the chemical hood if needed.
6. There should be no boisterous conduct.

4. 7. Never taste any laboratory chemical. Do not directly inhale the vapors.
8. Do not work alone in the laboratory.
9. Notify the instructor immediately of all accidents, incidents, injuries,
spills, or hazardous situations.
10. Dispose of waste chemicals in the containers provided.
11. Do not heat flammable liquids with a Bunsen burner or other open
flame.
12. Label all containers with chemicals or solutions of any kind.

5. Material Safety Data Sheet (MSDS)
Readily available information about the hazards of a chemical and also include basic information about chemicals.
1. Identification
2. Hazard(s) Identification
3. Composition/Information on Ingredients
4. First Aid Measures
5. Firefighting Measures
6. Accidental Release Measures
7. Handling and Storage
8. Exposure Controls/Personal Protection
9. Physical and Chemical Properties
10. Stability and Reactivity
11. Toxicological Information
12. Ecological Information
13. Disposal Considerations
14. Transport Information
15. Regulatory Information
16. Other Information

6. Globally Harmonized System for Classification and Labelling
of Chemicals (GHS)
• a standardized labeling system for chemicals, and the protocols for the determination of the hazard
ratings.

7. 4 General Accidents caused in Labs
• Fires
• Chemical Spills
• Contact with corrosive chemicals
• Reactions between incompatible chemicals

8. Fire Accidents
Causes
Due to the burning of easily flammable liquids or reactive metals or due to short circuit.
RAMP
 Recognize: The first step is to recognize the fire and alert others in the lab. Pull the fire alarm and call for emergency
services, if necessary.
 Assess: Assess the situation to determine the severity of the fire and the potential risks to personnel and the
environment. Determine whether it is safe to fight the fire or if evacuation is necessary.
 Minimize: Take immediate action to minimize the spread of the fire. Use appropriate fire extinguishing equipment to
extinguish the fire if it is safe to do so. Shut off any sources of ignition or fuel that could feed the fire.
 Prepare: Be prepared for any emergencies that may arise during the fire. Ensure that all personnel have been
accounted for and that they are safe. Provide first aid if necessary.

9. Types of Fires and Fire extinguishing in
Chemistry Laboratory

10. Fire extinguishing

12. Chemical Spills
A chemical spill is a situation in which a chemical is accidentally released. There are a number of things
which can cause a chemical spill. In a laboratory, a dropped beaker, piece of malfunctioning equipment, or
poorly handled package of chemicals can potentially cause a spill.
 Evacuate
 Communicate
 Isolate
 Mitigate

14. Spill Kits
For spills of liquids and solutions it is desirable to contain the spill with appropriate
materials. There are commercially available spill control “pillows,” “socks,” and “pads” that
absorb many times their own weight in acids, bases, and organic solvents.
These are an effective and safe way to minimize the spread of a spill and largely accomplish
a cleanup as well.
These containment devices often contain material such as shredded polypropylene filling,
which can absorb acids, bases, solvents, and oils. They do not neutralize acids or bases, but
only absorb them.

15. Corrosive Chemicals
Corrosives are defined as chemicals that cause harm or injury by damaging and
destroying tissue, such as eyes or skin, at the point of contact or the exposure
site. Corrosives can be gases, liquids, solids, or solutions.

16. RAMP
• • Recognize chemicals that are corrosive.
• • Assess the level of risk based on likelihood of exposure and concentration of the corrosive.
• • Minimize the risk by using a noncorrosive or less-corrosive chemical (if possible), eliminating exposure
possibilities by using chemical goggles and gloves and or working in a chemical hood.
• Add acid to water, when diluting concentrated solutions.
• • Prepare for emergencies by learning locations of eyewashes, safety showers, sinks, and spill kits.

17. Corrosives

18. Incompatibles Chemicals
Incompatible chemicals are combinations of substances, usually in
concentrated form, that react with each other to produce very
exothermic reactions that can be violent and explosive and/or can
release toxic substances, usually as gases.

19. Examples of Incompatible reactions are;
• Any soluble cyanide salt plus any strong acid produces toxic HCN gas:
NaCN(aq) + HCl(aq)→ NaCl(aq) + HCN(g)
• Any soluble azide salt plus any strong acid produces toxic and explosive HN3 gas:
NaN3(aq) + H2SO4(aq)→ Na2SO4(aq) + HN3(g)
• Any soluble sulfide salt plus any strong acid produces toxic and flammable H2S gas:
Na2S(aq) + 2HCl(aq)→ 2NaCl(aq) + H2S(g)

22. RAMP
 Recognize chemicals that you are using (or storing) that are considered to be “incompatible” with other chemicals. If
uncertain, do the necessary library or online research to learn more about unfamiliar chemicals.
 Assess the risk level when using or storing these chemicals. Review chemical procedures to assess the possibility that
incompatibles might unintentionally mix.
 Minimize risks by using incompatible chemicals only when necessary and limiting quantities that are used. Design
experimental procedures to minimize the chance for unintentional interaction between incompatibles. Store
incompatibles in separate locations. Minimize storage volumes by ordering only as much as reasonably necessary.
 Prepare for emergencies by knowing how to respond to unexpected reactions between incompatibles and how to
respond to spills.