laboratory management and safety good

LABORATORY MANAGEMENT AND SAFETY

1. INTRODUCTION

Improper utilization of laboratory equipment and chemicals has been observed in most of our senior secondary schools and laboratory running sectors. The equipment and chemicals have not been organized and stored to their respective places. In addition, pictures, charts and collections of plant and animal specimens are not organized properly.

Inventory of chemicals and equipment have several advantage in checking the loss and misplacement of items used up and /or lost etc. but inventory is not a common phenomenon in most of our school laboratories. Many of the laboratory assistants in our schools are not in a position of preparing reagents, handling instruments, performing activities by themselves.

Careless behavior in the laboratory can result in serious injury, health hazard and damage to property. Recognizing potential hazards and to avoid accidents from happening and to abide by the rules of the laboratory expected from the users of the labs, every person is expected to do their part to ensure a safe laboratory environment for themselves and others in the laboratory.

GOALS:

The goals of the laboratory are:-

1. Provide the services of a general lab, with basic equipment and chemicals for standard analytical and biological tests.

2. Ensure access to basic and safe working spaces for all users of the laboratory facility.

3. Provide access to workplace/desk space to researchers that need them.4. Provide the services of a library.5. Facilitate the tools and services required by the researchers to do their

studies.

2. LABORATORY MANAGEMENT

The Science Laboratory is a place where classroom teaching is further strengthened. The new facts and ideas lectured in the class will be confirmed in

Laboratory Management And Safety

the laboratory through the use of equipments, chemicals and specimens. It provides an opportunity to studyorganisms closely and to examine the various structures, processes, relationships, etc. which are characteristics of these organisms. It is here, therefore, that students develop skills, abilities and attitudes through the practical activities they carry out. Therefore, all laboratory facility should have to be managed to strengthen the classroom teaching.

The science teacher should make certain that the theoretical lesson is supplemented with the necessary practical work. Otherwise, the work is considered to be done partially, because the knowledge students are expected to gain along with the development of the required skills and abilities cannot be materialized. So the teacher must not consider laboratory activities as something additional that could be omitted, but as an integral part of the subject matter.

Some schools have separate laboratories for biology, chemistry and physics. Others have two labs for the three subjects. And there are still others that have only one laboratory. Variations also exist in water and electricity services, material distribution and storage facilities. This is partly because the schools have been constructed and equipped under different projects, public contribution and government budget. Being aware of these differences, which could only be solved step by step in the process of development, teachers have to put much effort and be creative enough to effectively use the resources at hand.

2.1. GENERAL LABORATORY MANAGEMENT RULES

1. Environmental protection is one objective of the labs. For this reason, a complete treatment of chemical wastes and biological wastes are required when possible. The Lab manager/assistant should know about chemical management, disposal and storage. Fungal and bacterial cultures should be autoclaved before they are disposed.

2. Turn off the lights and equipments when they are not in use including the extractor hoods.

3. When working in the lab, goggles and lab coats must be used. Gloves and masks appropriate for procedure must be used when necessary (i.e. Acid resistant gloves or asbestos gloves for hot objects).Vapor hoods, with the air extraction on, are to be used when working with hazardous volatile


materials with the fume shield partially closed to protect against splashes. Safety goggles must always be used when working in the vapor hood. All safety materials (goggles and masks) should be provided for the Lab.

4. Classify your garbage (glass, paper, plastic bottles and aluminum cans) and put it in the proper containers located outside the lab.

5. All solutions and samples should be labeled with the identification of their nature.

6. Balances, pH-meters are calibrated every day by the lab assistants.7. Refrigerator and freezer space is provided to store solutions or samples.

All solutions and samples must be properly labeled. Solutions must be stored in their own containers, not in lab glassware. Stored material that is not properly labeled can be discarded without warning.

2.2. ARRANGEMENT OF EQUIPMENT AND CHEMICALS

Laboratory equipment andchemicals are sent to schools in accordance with the curriculum demand. They are part of the essentials to fulfill the specific objectives of each portion in the course. Hence, they have to be used at the right time. The timely use of these materials however, can only be possible if there is a systematic approach to their arrangement and storage in the laboratory. Keeping materials according to their use and nature is time saving and is essential for safety and guarantees their prolonged use.

1. ARRANGING AND STORING EQUIPMENT

Materials having similar and related functions are kept together or in adjacent shelves. For example, Microscopes, Microscopic Slides, Cavity Slides, Cover Slides and Magnifying lenses should be placed together or should take adjacent shelves. Similarly, materials used for dissection such as scissors, needles, forceps, razors, etc. should have their own separate places.

It is always preferable to have closed storage space. When equipment and supplies are stored in closed cabinets, they are not exposed to dust, fumes or fluctuations in humidity and temperature.


Microscopes can be stored and easily counted in a cabinet made up of individual sections. This type of storage cabinet reduces the change for tumbling or knocking of the microscopes.

The wooden slide box, which is available in most of the schools, has to be effectively used for storing prepared slides. All the slides contained in the sections of the slide box should be indicated by writing on the corresponding serially arranged lines, printed on the inner surface of the slide box covering.

Once equipment is arranged, the specific place for each item should be indicated by labeling. If the materials are kept in cabinets and shelves with glass covers, the printed labels could be attached to the inner surface of the glass cover. However, if the containers have opaque covering, the printed labels should be placed on the outer surface of the covering and may be protected by a layer of transparent plastic sheeting.

After moving equipment from its place for actual use, return it immediately to its specific (labeled) place. Do not leave apparatus out after use!

Manage and use the Laboratory instruments and equipment according to their nature.

Analytical Equipment: The Laboratory has basic lab equipment such as scales, microscopes, magnetic stirrers, centrifuges, water baths, etc. The user must know the equipment function, operation, care and maintenance. If not, the user must request help from the Lab Assistant.

Any equipment or instrument used should be returned clean and in good shape.

Some instruments such as the gas chromatographs, the lyophylizer, and the spectrophotometer, are of limited use and are to be used only by persons who have previous experience with them.

Refrigerators and freezers: The refrigerators and freezers are used to store samples and reagents.

They are not allowed for food storage. The user should ask the Lab Assistant for assigning space in them. If the refrigerators and freezers are intended to be used only during

the researcher’s stay at the Station, any stored material must be clearly labeled with the following information:-


Researcher’s name Project name Content (Name of the reagent, sample, etc.) Preparation date Expiration date (if applicable) Date in which it will be taken out of the refrigerator or

freezer If anybody needs to keep things in refrigerators and freezers after

leaving the station, the Lab Assistant must be informed. Regularly, the lab personnel will review the contents of refrigerators

and freezers. If there objects that do not contain the above information, if the owner is not at the station any more, or if the storing date has expired, they will be disposed.

When using an oven, temperature should be checked periodically as a safety measure for fire.After using it, the oven should be turned off and cleaned.

The laboratory maintains basic glassware available for researcher use. After using glassware, it must be cleaned and dried. Any broken material must be reported to the Lab Assistant and disposed off in the appropriate container.

2. ARRANGING AND STORING CHEMICALS

The arrangement and storage of chemicals should be done based on the nature of the substances.

Certain chemicals react when placed close to each other. Glycerin and nitric acid, potassium chloride and organic compounds, cyanides and acids, etc. are among such chemicals.

Combustible and dangerous materials such as poisons should be securely locked in metal cabinets.

Acids, strong bases and substances like chloroform, ether, iodine and hormones should be stored in facilities, which can be locked.

Large storage bottles of acids, alkalies and other dangerous chemicals, if on shelves, are to be no more than two feet above the floor. If possible, they should be kept on the floor.


If there are metallic sodium, potassium, and calcium and calcium carbide in the lab, they should not be kept near or above containers containing water or water solution. Metallic sodium and potassium, after the original container has been opened, must thereafter be kept under kerosene.

The containers of chemicals that absorb moisture and change their chemical nature should never be left open. For example, Sodium Hydroxide, Sodium Carbonate and Sodium bicarbonate are hygroscopic. They absorb water from the atmosphere; as a result, their volume increases. The nature of the chemicals also changes.

3. ARRANGEMENTS AND STORAGE OF OTHER TEACHING AIDS: Pictures and

Charts

A drawer or filing cabinet filled with unclassified picture is practically worthless (valueless). To be effective, pictures must be put into some kind of order classification may be by topic, process, activity, or any other meaningful system.

Pictures may be mounted for longer use. When mounted they should be laminated between plastic sheets to ensure a longer life and to give a better appearance.

Many charts can be stored conveniently, and they are not exposed to wear and tear, when stored in hanging position. Each chart can be wired at one end and hooked on to the sliding arms of the cabinet. If each arm holds the charts dealing with a given topic in biology, teachers or students can find the charts quickly when they are needed. The teacher may hang the charts according to his filing system.

Models, skeletons, jar mounts and other specimens may be stored in cabinets that many drawers (if the school is equipped with such cabinets). They may also be kept in a storage cabinet that has a glass cover. The later also serves as a display case. If you are using open shelf storage space, you may cover it with transparent plastic sheeting to avoid the accumulation of dust.

If cabinets are not available, specimens and models can be stored and found most easily if they are kept in some uniform kind of container.


Plastic boxes, polythene bags, match and shoe boxes, tin lids, plates, etc. may be used. There is no rule. You can choose what you get cheaply and easily in your area. However, classification should be done.

When arranging models, skeleton and other specimens in cabinets, similarity and relations regarding structure and function should be considered. Finally, the materials should be properly labeled for identification.

Sometimes, to avoid smearing, printed labels can be placed inside a jar-containing specimen preserved in alcohol. The procedure is as follows:-

Print labels with India ink and set aside to dry until the ink no longer glistens.

Dip them into a jar containing 5 to 10% glacial acetic acid (use forceps).

Then drain the labels on blotting paper and insert into the specimen jars containing 70% ethyl alcohol.

NB. Strong paper should be used for labels because glacial acetic acid tends to soften the paper.

2.2. LABORATORY ETIQUETTE (RULE)

A. Your responsibility includes keeping your workstation properly. You will use equipment and parts stored in trays or drawers in an orderly fashion. Keep it in that order, for your own convenience.

B. Keep your work area uncluttered (organized). Store all instruments and components not actively in use in their proper place, away from your work area, or in the specials storage cabinets.

C. You may need other equipment and components stored in a different area from your workstation, perhaps in drawers or bins, or on shelves in the stockroom. Return these to their proper place immediately when you have finished with them.

D. Do not make unauthorized modifications to the equipment.

2.3. DUTIES AND RESPONSIBILITIES OF LABORATORY ASSISTANTS


The idea of assigning a lab assistant originate from the need to effectively utilize the laboratory and facilitate conditions, so that teachers and students can carry out all the compulsory practical activities which are necessary to attain the defined objectives of the lesson.

After a certain lab session, equipments and other materials may be found scattered in the laboratory. Plant specimens, soil samples and the like, brought to the laboratory by students, may be left to cover and spoil the benches and the floor. Used glassware’s may be found unwashed and need cleaning. Apparatus set up for experimentation need to be dismantled. Students may leave forgetting to return equipment and chemicals to their shelves. These and similar others, which affect the neatness and the readiness of the laboratory for next session, should be given careful attention by the laboratory assistant.

Sometimes the teacher may not have enough time to collect all the necessary materials and set-up an apparatus for an experiment or demonstration. The practical activity he wanted to perform may also require materials that need to be prepared ahead of time. For instance, if the teacher wants germinating seeds, he asks him to germinate seeds for him. He should get seeds soaked in water 4 to 8 days before the laboratory session. A reagent that can be prepared in the laboratory may also be needed for a particular experiment. This should be made ready for use whenever needed. Occasionally, equipment necessary to carry out an experiment may not be available in the laboratory. Under this condition, alternative method and improvisation will be found to be highly essential. The laboratory assistant in collaboration with the teachers is therefore expected to deal with the above and other related cases.

With this in mind, the following points are some of the duties and responsibilities of a laboratory assistant:-


this in mind, the following points are some of the duties and responsibilities of a laboratory assistan

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For efficient and smooth functioning of the laboratory, good understanding and close cooperation between teachers and the lab assistant is essential.

They (teachers) are expected to brief him on the use and handling of chemicals and sensitive instruments. Under no condition should the lab assistant be ordered to mix or treat chemicals he does not know. A planned and programmed


1. The laboratory assistant will take charge of laboratory equipment, apparatus and chemicals.

2. Will keep the laboratories open for use during class hours.3. Takes proper measures in the arrangement, organization and storage

of equipment, chemicals, specimens, charts, models, pictures, etc. regarding the laboratory, provides guide to pupils whenever necessary.

4. Controls the neatness and proper handling of laboratory rooms.5. Prepare necessary materials and set-up an apparatus for an

experiment or demonstration.6. The laboratory assistant checks the proper functioning of pipelines,

water taps, sinks, light bulbs, plugs, etc. If there are things that should be repaired, he reports to the office and follows up the case until proper measures are taken.

7. He will post up clearly written laboratory safety rules and precautions on the walls in the laboratory. Checks fire extinguishers to be conveniently placed and properly functioning. Makes sure that a first aid kit (equipment) is available in the lab.

8. Carries out the yearly inventory, registers materials lost, broken and used up, and reports for proper measures. He prepares certain laboratory formats, (as the ones indicated below to be used in the laboratory).

utilization of the lab will be necessary for maximum efficiency. Depending on the number of teachers and sections that make use of the lab, teachers along with the lab assistant should arrange a convenient timetable and work according it. This time table, which should enable each section to use the lab at least once in a week; helps avoid programme clashing and ensures that all teachers using the laboratory.

2.4. FORMATS IN THE LABORATORY

The laboratory assistant may prepare different kinds of formats to help him in his work. Some of the formats, if they are properly documented, serve as a source of information and give necessary data accurately. Among such formats, the following three are recommended to be used.

1.Requisition Format

Sometimes a teacher wants to take a model, chart or a specimen from the laboratory to show his students in the classroom. Another teacher may ask for certain equipment and chemicals for a class demonstration. It is part of the duty of the lab assistant to supply them with the needed materials. It is also his responsibility to see that the materials have been returned.

In entertaining such cases, using requisition formats will be of much help. It allows safe and timely return of materials borrowed from the lab.

Sample

BIOLOGICAL ITEM REQUISITION FORM

Date_______________

Name of the school______________

Teacher’s Name_________________

Grade and Section_______________

Unit_____________

Type of Activity_______________


Item Requested Quantity Condition

Chemicals _______________ _______________ _____________

________________________________ _____________

________________ ________________ _____________

Equipment ________________ ________________ ______________

________________ ________________ _____________

________________ ________________ _____________

Others___________________________________________________

Date of performance_________________________

Department Head Remark_________________________

Teacher’s Signature_________________________

Signature of the Dep. Head___________________

2. Format for Registering Materials Lost and Broken

One of the reasons why teachers refrain from effectively using the laboratory is the fear associated with the losing and breaking of the materials. Materials are kept in the lab to be used whenever needed. In fact, they may be lost for broken while in use. The important thing is to use them carefully. In case the materials are lost or broken while using them, the case should be immediately reported to the person who is in charge (the lab assistant or any other person assigned).

A form should always be ready to register the item lost or broken. The condition should be specified this then should be reported to the concerned committee for decision.


The committee is usually formed from people representing the administration, the laboratory assistant and teacher’s representative. Such a procedure allows avoiding the unnecessary arguments that arise between teachers and store keepers at the end of the academic year.

Sample

BIOLOGY LABORATORY FORM FOR REGISTERING MATERIALS LOST OR BROKEN

Name of the school____________________

Dat

e

Item Lost Orbroken

Quantity Specific Condition

Person In Charge

Signature Remark

By the end of the year, the form will be containing list of materials lost during the academic year, and hence helps as a reference for making all replacements and necessary preparations for the coming year.

3. Format for Recording Practical Activities Performed

In this form, experiments and demonstrations done are recorded along with the materials used. From among the compulsory experiments, those that cannot be done are also indicated and the reasons for not doing are also specified.

An experiment might have been omitted due to lack of materials. Another might have been found to be difficult to perform. A teacher might have also neglected an experiment which he thought was irrelevant to the subject matter. Whatever the reason may be, the teacher is expected to state it clearly in the form. This enables to know how many of the compulsory practical activities have been


carried out in the year and how many of them have not been conducted. The reasons stated (for not performing some of the experiments) also enable teachers to be in a position to give constructive comments on the use of the laboratory, the practical activities listed in the lab manuals and the curriculum as a whole.

Sample

BIOLOGY LABORATORY FORM FOR RECORDING PRACTICAL ACTIVITIES PERFORMED

Name of the School_______________________

Name of the teacher______________________

Dat

e

Topic Of Practical Activity

Un

it

Mat

eria

l U

sed

Gra

de

Sec

tion

Reason In Case Not Performed

Sig

.

Rem

ark

2.5. INVENTORY

In some schools, materials supplied at different timeswere found kept in the store for many years. In such schools, since yearly inventory is not done it is not possible even to know what materials are available.

The word inventory refers to the counting and listing of materials in the school store, laboratory etc. available, broken or lost. A properly carried out yearly inventory enables:-

To check the loss and misplacement of equipment To cross check with the previous counting To take corrective measures if difference are observed and find

the reason why the difference are seen To replace items used up and/or lost and maintenance.


For the proper handling and use of materials, the yearly inventory is very essential. The following points may be considered when carrying out the counting.

If materials in the lab are found to be unknown to the storekeeper or lab assistant, it will be necessary to ask the help of teachers for identification. If this does not solve the problem, instead of giving vague and irrelevant description, it is better to identify them using code (item) numbers.

A short description about the condition of the material will be helpful.

Registering quantities of the same item separately (under different serial numbers) will not be convenient for counting.

The list should include materials bought by the school, those prepared by teachers and students and materials obtained from organizations and individuals.

Separate lists should be prepared for materials in the three science laboratories.

2. LABORATORY SAFETY

2.1. Laboratory Safety Rules

Careless behavior in the laboratory can result in serious injury, health hazards and damage to property. Learn to recognize potential hazards, to avoid accidents from happening and to abide by the rules of the laboratory. Every person is expected to do their part to ensure a safe laboratory environment for themselves and others in the laboratory.

Some of the main rules that all individuals using the laboratory must abide by are:-

o No smoking, eating, and drinking in the laboratory.

o Horseplay is not allowed in the laboratory.

o Lab users must become familiar with the location and operation of the fire

extinguisher and other safety devices.


o If an individual has a question about the operation of a certain laboratory

device, the lab supervisor should be consulted. Equipment that you are not familiar with should not be used.

o Be aware of the biological and/or chemical agents are used in the

laboratory. Even if you are not performing experiments using hazardous agent, you should take appropriate precautions to keep yourself safe. Always wash your hands before leaving the laboratory and remove any gloves you are wearing.

General Laboratory Safety Rules

1. Smoking, eating, drinking

No smoking, eating, drinking, chewing, or applying cosmetics in laboratory areas. No food or drink is to be stored in laboratories (including refrigerators and freezers).

2. Disposable Laboratory Gloves

Disposable laboratory gloves are not to be worn in communal areas. Door handles, telephones, computer keyboards (except in clearly labeled circumstances), lift buttons, etc. are not to be touched with gloves. If needle, wear one glove and use the un-gloved hand to open doors, operate lift etc.

Rubber or disposable gloves should be worn when handling/working with:

Human blood or other body fluids Dangerous chemicals Potentially infectious material

3. Laboratory Gowns or Lab Coats

Laboratory gowns or lab coats must always be worn in laboratories, and they must be removed before entering “clean areas”, e.g. the tea room, stores, toilets, library, office areas, etc. The gowns or coats must be of sufficient length to protect the worker (i.e. down to about the wearer’s knees). They must close at the back or, if front-closing, have enough overlap at the front to prevent gaping.

4. Clothing, Footwearand Hair


Clothing and footwear must be suitable for laboratory conditions, i.e. clothing must not present any hazards by being too loose, accessories must not present a hazard during laboratory work, etc. and footwear must be fully enclosed. If you want to wear other shoes to and from work, etc. you might want to keep a pair of fully enclosed shoes at work to wear in the lab. Thongs, or barebacked sandals or shoes, or very high heels must not be worn in the laboratory. Bare feet are also prohibited. Long hair must be tied back to avoid contact with microorganisms and equipment.

5. Safety Glasses

Full-face shields must be worn for all work involving corrosive or toxic liquids, ultra-violet light.

6. Avoiding Ingesting Microorganisms

The best protection to ingesting microorganisms is not to put them in mouth. Pencils and pens must not be placed in the mouth. Chewing of fingernails, playing with hair, applying lipstick, drinking, etc. are not allowed. Wash your hands when leaving the laboratory togoto lunch, etc.

7. Pipetting

Do not pipette by mouth. The use of pipettes with cotton plugs to reduce contamination is preferable place pipettes in disinfectant solution tip-first to minimize aerosol production. Submerge for 18-24 hours. Residual volumes from pipettes create aerosols; use mechanical devices that are calibrated to deliver.

8. Syringes and Needles

Restrict the use of “sharps” to a minimum. Avoid using syringes to mix infectious liquids (if essential, hold the tip of the needle under the surface of the fluid and avoid excessive force). Discard used syringes and needles into an approved container.

9. Hazardous Chemical/Biological Spills


Hazards chemical and biological spills and blood spills on floors, benches or equipment should be cleaned up immediately. Special treatment is required for spills of a bio hazardous nature.

10. Hand Washing

Hands should be washed after completing each task and always before leaving the laboratory.

11. Faulty Equipment

Any faulty equipment should be removed from service for repair or disposal.

12. Corridors and Exits

Corridors and exits must not be obstructed by equipment or stored items.

13. Bench Work

Minimize aerosol production when carrying out on an open bench. Place bench coat or a similar absorbent paper over working surfaces. Replace this regularly. Decontaminate workbenches after spills and after work has been completed.

14. Fungal Spores

Petri dish cultures of fungi should be sealed and incubated with the lid uppermost to prevent the dispersal of fungal spores. Recognize fungi as potential pathogens and be aware of the ability of some species to produce mycotoxins.

15. Petri Dishes

Take care when handling petri dishes that contain condensate. This may contain viable microorganisms that can be spread via droplets or aerosols when the plates are opened or dropped.

16. General Behavior

No running or “horse play” in the lab.

` Before You Attend Any Biology LabDO’s: DON’T’s:Read your lab manual “Safety” section Think that ignorance is bliss.


Know the work procedures for each day.

Forget your lab manual and rely on your memory.

Know the dangers. Have a casual attitude.Plan to wear a lab coat. Wear your best clothes.Be well rested and alert. Sleep-in and arrive late.Notify the lab instructor of any relevant medical condition.

Hide a medical condition that might jeopardize your safety or the safety of others.

NO ONE SHOULD EVER ADOPT A COMLACENT ATTITUDE TOWARDS LAB SAFETY.

2.2. Other Safety Rules When Working In Biological or Chemical Laboratory

1. Personal Safety

The highest priority in the laboratory is personal safety. Therefore you must be sure to:

Wear eye protection in the laboratory when handling any chemical or biological agents. Tie your hair back, if you have long hair.

Wear protective gloves when handling corrosive chemicals or biological agents. These are not to be worn in non-lab areas. (i.e. remove them before going to the washroom).

Wear a lab coat and closed-toed shoes, when in the lab.o Lab coats used in labs should not be worn in non-

laboratory areas. Laboratory coats are to be worn INSIDE the laboratory BUT have to be removed when leaving the work area.

2. Chemical Hazards Safety

When performing experiments:

Wear protective gloves.


Read the lab before using any reagent. Never pipette by mouth (even water); use a device such as a

pipettor. Never taste chemicals and smell them only cautiously. Never use the biological and safety cabinets as fume hoods. Never pour chemicals down the sink without first consulting

Supervisor.

3. Biological Hazards Safety

Although you may not be working with pathogenic organisms, you should be aware of safety procedures in dealing with biological agents in general.

All persons working with biological agents must observe the following rules:

Wear a lab coat. Clothing coming in contact with biological agents should be removed and washed.

Keep the laboratory doors closed. Wash your hands thoroughly with soap and water before

leaving the laboratory. Place any non-sharp implements that you used to handle

biological agents into appropriatecontainers. Place all used microscope slides in disinfectant. Never place cell culture vessels close to the edge of the lab

bench and in areas where they could be knocked over. Never leave cultures open to the air: keep them covered at all

times. Many biological agents can become airborne and inhalated.

No mouth pipetting at any time. No smoking, eating or drinking in the laboratory. A lab coat must be worn whenever work involving biological

material is being carried out and must be taken off before visiting non-laboratory areas (coffee rooms, shops, libraries, etc.).

All contaminated glassware must be disinfected before being placed for washing up.


All spillages must be wiped up with either disinfectant or ethanol including spillages in centrifuge rotors.

All materials which are potentially infectious should be inactivated (by disinfection or by autoclaving) before leaving the lab for incineration.

Care must be taken when using any procedure which generates aerosol, to minimize exposure to potentially infectious agents.

Wash your hands before you leave the laboratory.

Potentially hazardous biological specimens:

1. Human cell line (including non-human primates).2. Non-human cell line.3. Human or other primate sample (fluid, tissue, etc.).4. Non-primate sample (fluid, tissue, etc.).5. Bacteria.6. Virus.7. Fungus, parasite, or other live material.

Potential Causes:

1. Oral aspiration through pipettes.2. Accidental syringes.3. Animal bites.4. Spray from syringes.5. Centrifuges accidentals.6. Cuts and scratches.7. Animal wastes.8. Direct contact with pathogenic cultures.

2.3. Safety Considerations Associated With Some Specific Instruments/Equipments

A. Biological Safety Cabinets

Biological safety cabinets have been installed in some laboratories for two reasons:


1. To maintain sterility in your experiments.2. To protect the user from the experiment, so that the user has

minimal contact with the biological and chemical agents.

For maximum safety and experimental success, use the biological safety cabinet as much as possible when using biological media.

Techniques for the use of biological safety cabinets:

1. The use and limitations of biological safety cabinets should be explained to all potential users, with reference to national standards and relevant literature.

2. The cabinet must not be used unless it is working properly. 3. The glass-viewing panel must not opened when the cabinet is in

use.4. Apparatus and materials in the cabinet must be kept to a minimum

and at the rear of the working area.5. All work must be done in the middle or rear part of the working

surface and should be visible through the viewing panel.6. The operator should not disturb the airflow by repeated removal

and reintroduction of his or her arms.7. The cabinet fan should be run for at least 5 minutes before and

after completion of work in the cabinet.

B. Centrifuge

Centrifuges can be a hazard for two reasons:

1. The components remove at extremely high speeds and if they are not balanced, there is a possibility for a mechanical hazard.

2. Usually the centrifuge is used for potentially bio-hazardous media, so care must be taken to avoid spillage of the media. If spillage occurs, proper decontamination must take place.

Techniques for the use of centrifuges:

1. Satisfactory mechanical performance is a prerequisite of microbiological safety in the use of laboratory centrifuges.


2. Centrifuges should be operated according the manufactures’’ instructions.

3. Centrifuges should be placed at such a level that workers of less than average height can see into the bowl to place trunnions and buckets correctly.

4. Centrifuge rotors and buckets should be inspected daily for signs of corrosion and for hairline cracks.

5. Buckets and trunnions should be paired by weight and, with tubes in place, correctly balance.

6. Alcohol (70%) should be used for balancing buckets. Saline or hypochlorite solution should not be used as both corrode metals.

7. Securely capped tubes and seal able centrifuge buckets offer adequate protection against infectious aerosols and dispersed particles of microorganisms.

C. Autoclaving for Sterilization

Individuals responsible for autoclaving glassware and other lab ware will be responsible for preparing the materials for sterilization.

Refrigerators and Freezers

Techniques for the care and use of refrigerators and freezers:

1. Refrigerators, deep-freezers should be defrosted and cleaned periodically and any ampoules, tubes, etc. that have broken during storage removed. Face protection and heavy-duty rubber gloves should be worn. After cleaning, the inner surface of the cabinet should be disinfected.

2. All containers stored in refrigerators, etc. should be clearly labeled with the scientific name of the contents, the date stored and the name of the individual who stored them. Unlabeled and obsolete materials should be autoclaved.

E.Pipetting

1. Pipetting by mouth should be prohibited. A pipetting aid always is used.


2. All pipetters should have cotton plug to reduce contamination of pipetting devices.

3. Infectious materials should not be mixed by alternate suction and expulsion through a pipette.

4. Liquids should not be forcibly expelled from pipettes.5. To avoid dispersion of infectious material if it is accidentally

dropped from a pipette, a disinfectant-soaked cloth or absorbent paper should be placed on the working surface; this should be autoclaved after use.

6. Contaminated pipettersshould be completely submerged in a suitable disinfectant contained in an unbreakable container. They should be left for 18-24 hours before disposal.

7. Glassware and Sharps Handling:

Protect your hands when assembling glassware equipment. Place all sharps, glassware and contaminated items (glass pipettes,

needle, etc.) into designated containers for disposal. Sharps and glassware need to be decontaminated before disposal.

Clean all broken glassware promptly and dispose of properly into the proper container. Use a brush and not your bare hands.

Ensure that needle and blade sharps are separately and carefully collected in sharps waste container. When full, these containers are to be disposed of properly.

2.4. Other Safety Considerations

A. Chemical or biological media spills

Chemical/Biological spill kits are to be used only for very small spill. Clean up kits should be in every lab.

Fire Safety

When working in the laboratory, read the chemical label and determine if a substance is dangerous (flammable, corrosive or toxic) before using it.


Keep all bottles of flammable, toxic and corrosive chemicals closed and in the appropriate cabinet unless they are in use.

Keep open vessels of solvent away from source of heat or sparks. If your clothing is on fire: stop, drop and roll on the floor to

smother the flames. Know where the fire extinguisher is located. Know where the fire exits are. Check all electrical equipment before you turn the power on.

General Housekeeping

The best way to avoid accidents is to develop good housekeeping. Keep your workplace clean and tidy. Clean up spills, broken equipment, floods and general clutter promptly.

WASTE DISPOSAL

A.BIOLOGICAL WASTE

Biological waste includes:

Liquids such as used cell culturing media, supernatant, blood or blood fractions (serum),etc. which contain viable biological agents;

Materials considered pathological, any part of the human body, tissues and bodily fluids.

Any part of an animal infected [or suspected to be infected] with a communicable disease;

Non-sharp, solid laboratory waste (empty plastic cell culture flasks and petri dishes, empty plastic tube, gloves, wrappers, absorbent tissues, etc.) which may be, or is known to be, contaminated with viable biological agents;

All sharp and pointed items used in medical care, diagnosis, and research, including the manipulation and care of laboratory animals, which should be considered potentially infectious;

Laboratory glassware, which is known or suspected to be contaminated with hazardous biological agents.

Packaging and Treatment


Materials contaminated with hazardous biological agents must be collected in the appropriate containers and sterilized or disinfected before disposal.

a) Liquids containing bio hazardous agents Collect liquids in leak-proof containers such as flasks or bottles. Liquid waste containers designers to withstand autoclaving

temperatures must be used when steam sterilization is utilized.

b) Solids containing bio hazardous agents

Non-sharp, solid laboratory waste (empty plastic cell culture flasks and petridishes, empty plastic tubes, gloves, wrappers, absorbent tissues, etc.) which may be, or is known to be, contaminated with viable biological agents should be collected in autoclavable bags. These plastic bags display the biohazard-warning symbol.

For laboratories generating large volumes of agar gel in disposable Petri-dishes and tubes requiring sterilization, such waste should be collected and sterilized.

c) Sterilization and Disinfections

Inactivate the biological agents by employing either chemical disinfection or steam sterilization procedures.

Autoclaving (steam sterilization) is the preferred (and generally regarded as the most reliable) method of sterilizing biological waste. Depending on the volume of waste to be sterilized, it may be necessary to extend the duration of exposure to high temperature steam under pressure. or


Note: Autoclavable bags should be used for solid, non-sharp, hazardous biological waste only and disposed of appropriately. They should not be used for the collection of other solid hazardous or nonhazardous waste that may require other treatment or disposal methods.

Plastic disposable pipettes are disposed into appropriate container and then soaked in disinfectant for a period of several hours.

Contaminated glassware should be thoroughly soaked in disinfectant for a period of several hours before placing in the washing up.

All contaminated glass or plastic should be washed and thoroughly decontaminated.

Following steam sterilization or chemical disinfections, innocuous liquids may be disposed of via the laboratory drainage system. Flush with sufficient clean water to purge the drain immediately after disposal of all liquids.

Do not pour melted agar into sink or floor drains. All it to cool and solidify for disposal as a solid waste.

B.CHEMICAL WASTE

1. Improper Labeling of Waste

Typical examples include:

a. Failing to label a waste bottle. If the contents of the bottle are not listed, the next person to use the bottle could accidentally combine incompatible chemicals, causing a fire and explosion. All bottles of chemical waste must have information on it.

b. If something isn’t really waste, don’t pit the word “waste” on the bottle.

c. Scratching out the former label of the bottle and writing “waste” on the bottle. You must remove or totally deface the old so there is no confusion over the contents.

2. Improper Segregation of Waste


a. Storing acids and bases in the same cabinet. Leaking containers or a spill could cause a violent reaction, which would release large quantities of toxic gases.


b. Storing acids and organic waste in the same cabinet. In the event of accidental mixing, a catastrophic fire or explosion could result.

c. Mixing incompatible chemicals in a waste container. For example, nitric acid and ethanol can form an explosive mixture.

3. Improper Storage of Waste


a. Using metal cans for waste. Even near neutral pH, solids and liquids can easily corrode through metal cans in a surprisingly short period of time. Use only glass or polyethylene containers for waste.

b. Storing waste bottles in or near a sink or floor drain. This could allow toxic chemicals to enter the sewer.

4. Taking Waste to the Stockroom

1. Bring your waste to the stockroom

o All waste containers must have a proper “hazardous waste” label

with start date here’s an example:

o All contents are listed.

o The bottle or jar has a cap that fits tightly.

o There are no or extraneous labels on the container.


HAZARDOUS WASTE

ACCUMULATION

START DATE MAY 29, 1997

CONTENTS acetone, diethyl ether

HANDLE WITH CARE!

CONTAINS HAZARDOUS OR TOXIC WASTES

o The outside of the bottle is clean and dry.

Chemical containers that have been empties (generally this means drained their contents by normal methods including pouring, pumping, aspirating, etc.) are not regulated as hazardous waste; however they should not necessarily be disposed of in the regular solid waste dumpsters. Generally, the primary container (the container that actually held the chemical, as opposed to a container that the primary chemical was packed in), must be triple rinsed with water or other suitable solvent and air-dried before disposal. For volatile organic solvents (e.g. acetone, ethanol, ethyl acetate, ethyl ether, hexane, methanol, methylene chloride, petroleum ether, toluene, xylene, etc.) the emptied container can be air-dried in a ventilated area without triple rising.

Glass containers must be triple-rinsed with water or other suitable solvent and air-dried to ensure that it free of liquid or other visible chemical residue.

If the glass container has visible residue and this residue is hazardous, the container should be disposed with appropriate care. If the residue is not hazardous, the intact container should be placed in regular lab trash.

Broken glass containers that are free of chemical residue should be placed in broken glass receptacles or placed in a puncture resistant container, such as a rigid plastic container. The plastic container or box should be sealed and placed in regular laboratory trash.

Metal containers must be triple-rinsed with water or other suitable solvent and air-dried. If the container is free of hazardous chemical residues, it may be placed in the regular laboratory trash. Otherwise, it should be disposed with an appropriate care.

Controlling practices for infectious agents

The control of biological hazards in the laboratory shall be maintained by:


Limiting the handling of material to the minimum amount Ensuring proper disposal of material after usage Ensuring proper precautions and procedures when handling the

materials Maintaining appropriate levels of identification (universal bio-

hazard warning label) warning and security in storage of the material.

2.7. Emergency Procedures

There are many types of emergencies that could occur in a laboratory, including fires, chemical/biological contaminants spills, injuries, accidents, explosions and others.

1. Fire

In the event of a fire:

1. Individuals are not required to fight fires; but that those who choose to do so may fight small, incipient stage fires ( No bigger than a waste paper basket) as long as have been trained in theproper use of fire extinguishers.

If you have been trained in the use of a fire extinguisher, fight the fire from a position where you can escape, only if you are confident that you will be successful.

A fire contained in a small vessel can usually be suffocated by covering the vessel with a lid of some sort.

2. If your clothing catches fire, drop to the floor and roll to smother the fire. If a co-worker’s clothing catches fire, knock the person to the floor and roll him or her to smother the flames. Use a safety shower immediately thereafter.

3. If the fire is larger or spreading inform the building occupants by fire alarm or notify the building occupants verbally of the need to evacuate. If possible, shut down any equipment, which may add fuel to the fire. Close the door behind you to prevent the fire’s spread.

2. Chemical Exposures


The following procedures should be followed in the event of chemical exposure.

Chemicals on Skin or Clothing

Immediately flush with water for no less than 15 minutes. For larger spills, the safety shower should be used.

1. While rinsing, quick remove all contaminated clothing.2. Use caution when removing sweaters to prevent

contamination of the eyes.3. Discard contaminated clothing or launder them separately

from other cloth. Chemicals in Eyes

1. Immediately flush eye(s) with water for at least fifteen minutes. The eyes must be forcibly held open to wash, and the eyeballs must be rotated so all surface area is rinsed. The use of an eye wash fountain is desirable so hands are free to hold the eyes open. If eyewash is not available, pour water on the eye, rinsing from the nose outward to avoid contamination of the unaffected eye.

2. Seek medical attention. Chemical Inhalation

Close containers, open windows or otherwise increase ventilation, and move to fresh air.

1. If symptoms, such as headaches, nose or throat irritation, dizziness, persist, seek medical attention.

Accidental Injection of Chemicals

Wash the area with soap and water and seek medical attention.

Biological hazards spills

If potentially hazardous biological material is spilled in the laboratory:

Avoid inhaling any airborne material by holding your breath and leaving the laboratory


Close the door to the laboratory and warn others in the area go to a wash or change room area. Wash all potentially contaminated area as well as the arms, face, and hands.Shower if facilities are available

If clothing is known or suspected to be contaminated, remove the clothing with care, folding the contaminated area inward. Discard the clothing into a bag or autoclave

Reentry into the laboratory should be delayed for a period of 30 minutes to allow reduction of the aerosol generated by the spill.

NB.Contaminated gloves, wiping cloth, and sponges should be discarded into an autoclave pan and autoclaved.

Emergency services: whom to contact

The telephone numbers and address of the following should be prominently displayed near all telephones:

The institution or laboratory itself Safety officer Fire services Hospital/ambulance service Police Director or institution or laboratory Engineer Water, gas and electricityservices.

Emergency equipment

The following emergency equipment must be available:

First aid kit Stretcher

2.8. Laboratory design and facilities

1. The laboratory should be separated from the areas that are open to unrestricted traffic flow within the building. Additional separation


may be achieved by placing the laboratory at the blind end of a corridor

2. Access to the laboratory area must be designed to prevent entrance of arthropods and other vermin.

3. Access doors must be self-closing and lockable.4. The surface of walls, floors and ceilings should be water-resistant and

easy to clean. Opening in these surface (e.g. for service pipes) should be sealed to facilitate decontamination of the room(s).

5. A foot-or elbowoperated hand-washbasin should be provided near to each exit door.

6. Exhaust air form the laboratory must be discharged directly to the outside of the building so that it is dispersed away from occupied buildings and air intakes. It is recommended that this air is discharged through high-efficiency particulate air (HEPA) filters.

Definition:

A potentially hazardous biological specimen may be any one type or combination of the following types of specimens, when such a specimen consists of live, frozen or lyophilized material that may possess the potential to produce an infection or genetic alternation in humans, animals or plants.

Potentially hazardous biological specimens do not include live animals that are healthy and pressure to be non-infectious, but do include unhealthyanimals that are known or suspected to be infectious.

Biological specimens are not considered to be potentially hazardous when the specimens have been chemically, thermally, or otherwise treated to render the specimens, or component thereof, permanently non-viable, permanently inactivated, or permanently incapable of insertion or infection into living cells.

Hazards in bio labs are principally due to infections. Additional Hazards Include:

Chemical Mechanical Fire


JIMMA

TEACH

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Electrical Radiation

= The End =


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