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Laboratory
Is the special room that have been designed and equipped for carrying out scientific experiments for the purposes of study or research
OR
Is a working room for scientists
Examples of Laboratories are;
- Clinical laboratory
- Physics laboratory.
- Biology laboratory.
- Chemistry laboratory
Laboratory rules
Are the guidelines to be followed in the laboratory in order to reduce risks of accidents
The following are some of the physics laboratory rules.
1. Don't enter in the laboratory without permission from your teacher or laboratory assistance.
2. Never fight in the laboratory
3. Do not eat or drink in the laboratory
4. Do not run or play in the laboratory
5. Do not use laboratory container for drinking or storing food
6. Wash your hands with soap before you leave the laboratory
7. Don't perform any experiment in the laboratory without permission from your teacher or laboratory assistance.
8. All exits must be clear of abstraction/ obstacle.
9. Any damages that may occur must be reported immediately to the laboratory attendant technician.
10. All damaged or broken apparatus must be well deposited to a proper place. 11.Never use free hand to hold hot objects.
11. Replace immediately the cover or stopper of the particular chemical soon after use.
12. After experiment, clean the bench and leave it dry and well arranged.
13. All connections must be checked by laboratory attendant/technician in case of electrical experiments.
Features of a Laboratory
A good laboratory should have the following features
- Water supply system
- Drainage system
- Electricity supply
- Well illuminated
- Well ventilated
- Door opens out ward
- Gas supply
Laboratory Apparatus
Is a special tool or instrument commonly used to carry out the experiments in the laboratory
Laboratory Apparatus
| Item | Uses |
| Measuring cylinder | For measuring volume of liquids |
| Thermometer | For measuring temperature of substances |
| Stop watch | To measure time |
| Micrometer screw gauge | For measuring diameter of a wire |
| Vernier caliper | For measuring depth, length, internal and external diameters of objects |
| A ruler | For measuring length |
| Relative density bottle | For measuring relative density |
| Microscope | For magnifying very small objects |
| Beaker | Used as container for chemicals and other liquids. Also can be used to estimate the volume of liquids |
| Spring balance | For measuring force in Newton |
| Slotted masses | Used for measuring for the quantity of matter. |
| Magnets | For demonstrating attraction and repulsion |
| Ball and ring apparatus | For demonstrating thermal expansion |
| Bar breaking apparatus | To show forces that can be exerted during thermal expansion and contraction |
| Tripod stand | For providing a platform for heating for stability |
| Wire gauze | For providing equal distribution of heat while burning |
| Bunsen burner | As source of heat |
| Retort stand | For holding/gripping materials |
| Triple beam balance | Measuring mass |
| Flasks | For holding liquids during experiment |
| Electronic balance | For measuring mass in more precise values |
Laboratory Safety
Is the situation in which laboratory users can be protected from danger, risk or injury
Laboratory Safety includes: -
1. Laboratory should be well ventilated and his door should open outward
2. Fire extinguishers should be fitted in an accessible position with using instruction
3. Laboratory floors should not have polished to avoid slippery
4. First aid kit must present in the laboratory
5. Cabinets and drawer must present for storing apparatus
6. All apparatus should have checked regularly to ensure they are safe to use
7. Emergence exit should present and easy to access and use
First Aid
Is the immediate assistance given to a victim before getting professional medical help
OR
Is an immediate care given to an injured person before she/he is taken to a nearby hospital for further medical treatment.
Importance of First Aid
1. It helps to preserve life
2. It prevents the victim's condition from becoming worse
3. It promotes recovery by bringing hope and encouragement to the victim
4. It helps to reduce pain and suffering
5. It prevents infection
First Aid Kit
Is a small box used to store instruments and chemicals needed for first aid.
OR
Is a small box containing items that are used to give help to a sick or injured person.
Usually labeled as "FIRST AID" and stored in a safe and easily accessible place
The following table summarizes the items which are found in the first Aid kit
| Item(s) | Uses |
| 1.A pair of scissors | To cut adhesive tapes, bandages and gauze |
| 2. Rolls of adhesive tape | To hold firmly into wounds, bandages, gauze and cotton wool. |
| 3. Bandages and cotton wool | To clean and cover wounds. |
| 4.Sterilized new razor blade | Used in treating fresh or old wounds |
| Item(s) | Uses |
| 5. Sterilized gauze | To clean and cover wounds |
| 6.Safety pin | To tighten clip bandages |
| 7.One Jar petroleum jelly | To apply on burns |
| 8. Iodine tincture | To clean fresh cuts and bruises |
| 9.Antiseptic soap | To wash hand and wounds |
| 10. Antibiotic solution | To clean wounds. |
| 11.Painkillers | RelieRveinligeving pain |
Causes of Laboratory Accident
1. Slippery floor,
2. Incorrect use and handling of apparatus,
3. Gas leakages from faulty gas taps,
4. Fires,
5. Improper arrangement of laboratory instruments and chemicals.
6. Playing, fighting or quarreling in the laboratory.
7. Deviating from instruction for using chemical reagents or laboratory equipment.
8. Performing unauthorized experiment or deviating from instruction of experiment.
9. Insufficient personal protection when performing an experiment
10. Improper handling of potentially dangerous chemicals.
11. Ignoring laboratory rules.
The following are the ways used to minimize accidents in the laboratory:
Through following laboratory rules and safety precaution.
By using protection wears before beginning any experiment.
Proper arrangement of laboratory instruments and chemicals.
First Aid Procedure
Is the step-by-step process taken in order to help the victim when accident occurs
The following procedures may be used: -
A. Electric Shock
When dealing with a victim of electric shock, remember to take the following actions
1. Do not touch the victim who still in contact with electric current.
2. BREAK the contact by switching off the current at the switch or meter box if can be reached easily
3. If it is not possible to switch off the current, move the person from the current using a dry non-metallic object, for instance a piece of dry wooden plank or a bloom
4. If you suspect that the area has high voltage electricity, call for professional help immediately
5. If the victim is unconscious, check the breathing and pulse rate. If he or she has breathing problem, he prepared to resuscitate if necessary
6. Administer First Aid for shock, burns or other injuries sustained by the victim.
7. Seek medical assistance
B. Cuts (Or Wounds)
For a small cut or wound:
Wash your hands using soap and cleaning water.
Put on your gloves.
Wash your wounds using salty water and clean cloth.
Cover the wounds or cut with an adhesive bandage or plaster.
For a large cut or wounds:
Let the victim lay under a shade or allow her to sit comfortably.
Wash your hands using soap and clean water.
Put on your gloves.
Prevent further blood loss by applying pressure over the wound using a folded but clean handkerchief or cloth.
Use another cloth to secure the first one in place.
Take the injured person to hospital.
C. Fainting
Fainting is the situation where by victim is weak and unable to stand. It is caused by too much heat and congestion
Steps to Help a Victim
1. Take the person to a cool place or under a shade
2. Let him lie on his back with his legs raised higher than the head.
3. Loosen his clothes and ensure sufficient supply of air
4. Dip a clean handkerchief in water and press on his forehead.
5. Give him/her clean water to drink when he regains consciousness
6. If not, take the victim to the nearest hospital
FIRE
Is the state (process) of combustion that results into light, heat, smokes and flame
Fire Triangle
Are the components needed to start a fire.
These include
a) Fuel
b) Oxygen
c) Heat
Causes of Laboratory Fire
a) Electrical faults
b) Smoking materials
c) Carelessness
d) Ignorance and negligence
Basic Principles of Fire Prevention
i. No lighting of open fires near buildings
ii. No smoking in prohibited areas
iii. No interference with electrical installations
iv. All electrical appliances must be switched off after use
v. All sources of heat should not be kept near the bench edge where they can easily be knocked down
vi. All flammable substances should be locked up in drawers or cabinets
Fire Extinguisher
Is the one in which is used to fight or stop fire to continue
Types of Fire Extinguisher
i. water extinguisher
ii. Sand extinguisher
iii. Fire Blanket extinguisher
iv. Dry powder extinguisher
v. Carbon dioxide extinguisher
vi. Foam extinguisher
vii. Wet chemical extinguisher
viii. ABC extinguisher
Mechanism of fighting for Fire
Fire extinguisher stop fire by preventing one among of the fire components/fire triangle
Classes of Fire
Fire is classified according to materials burnt; therefore, we have six classes of fire namely
Class A Class B Class C Class D Class E Class F
| Fire class | Burning material | Suitable extinguisher |
| CLASS A | Organic solids (wood, paper plastics etc) | Water |
| CLASS B | Flammable liquids and greases (Petrol, Paraffin and alcohol) | Dry Powder |
| CLASS C | Flammable gases (methane, LPG ) | Dry powder |
| CLASS D | Combustible metals (Magnesium or sodium) | Dry powder |
| CLASS E | Electrical hazards (damaged electrical cables, switch boards) | Carbon dioxide |
| CLASS F | Cooking oils and fats (deep fat fryers) | Wet chemical |
NB: There is NO one extinguisher type which works on all classes of fire
Warning Signs
Warning sign is the symbol established to ensure safety in the laboratory and in other fields like goods or commodities. This sign should have obeyed to avoid accidents, include the following
| Toxic | Irritant (harmful) | Flammable |
| Corrosive | Radio Active | Danger of electric shock |
| Fragile | Explosive | Careful |
| Flammable | Keep away from water | Oxidizing agent |
Toxic
Toxic symbol means that a substance is dangerous and can cause death within a short time.
Toxic substances containing poisonous ingredients, examples of toxic substance are jik, mercury etc
Toxic substance enters the body through Ingestion (by eating and drinking), Inhalation (by breathing) ,by injection and Contact
Irritant (Harmful)
It means that a substance is dangerous and can affect our health for long time.
Examples are alcohol, paint, insecticide, tobacco, ammonia etc
Flammable
It means that the substance can catch fire easily.
For example, gasoil, kerosene, petrol, butane, methane, spirit,
Oxidizing Agent
It means that the substance can speed up the rate of burning.
For example, oxygen gas, chlorine gas, fluorine gas and hydrogen peroxide
Corrosive
The symbol means that the substance causes gradual change when in contact with various materials.
Radio Active
It means that the substance emits harmful radiations that penetrate the human body and cause damage. For Example, uranium, plutonium etc
Danger of Electric Shock
It means that the substance has high voltage which you should not touch.
Fragile
It means that the substance should be handled with care to prevent them from breaking. For example, glass etc.
Explosive
The symbol means that the substance can erupt (explode) easily.
Never store explosive material in glass container because when explode pieces of glass would fly all over and injure people
Careful
The symbol is the caution (advice), you need to be carefully
Keep Away from Water
Is the caution (advice) you have to keep items away from water.
For example, computer, mobile phones, radio etc
Scientific Investigation (scientific procedure)
Scientific method is a set of techniques used by scientists to investigate a problem/answer question
Steps of a Scientific Method
The following are steps followed when carrying out a scientific investigation
1. Problem identification
2. Asking questions
3. Formulation a testable hypothesis
4. Performing an experiment
5. Data collection and analysis
6. Data interpretation
7. Data presentation
8. Drawing a conclusion
Significance of the Scientific Procedure
1. It helps us to solve scientific problems
2. It helps us to gain new knowledge
3. It helps us to conduct project work
4. It helps us to carry out field study
5. It helps us to solve problems or answer scientific questions
Assignment
1. Define the term laboratory.
2. Describe the common features of a science laboratory.
3. Explain why one should know the laboratory safety rules before entering or starting any activity in the Science Laboratory.
4. Mention some of the rules which ensure safety in the Science Laboratory.
5. What are warning signs?
6. Mention types of laboratories
7. State five classes of fire and their most appropriate fire extinguishers.
8. Mention safety measures that protect your body from the dangers of an experiment you are doing.
9. Draw the following apparatus and state their uses
i. Beaker
ii. Thermometer
iii. Micrometer screw gauge
iv. Measuring cylinder
9. List down at least four accidents that are likely to occur in the science laboratory
10. What do you understand by First Aid? 13.What is the importance of first Aid?
11. List ten (10) contents of the first Aid Kit.