Essentials of Laboratory Safety
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Essentials of Laboratory Safety Heather D. Durham, PhD Chair, Laboratory Safety Committee Montreal Neurological Institute. Slides adapted from: Mr. Wayne Wood, Manager , Environmental Health and Safety, McGill University and

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Slides adapted from: Mr. Wayne Wood, Manager ,

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Slides adapted from mr wayne wood manager

Essentials of Laboratory Safety

Heather D. Durham, PhD

Chair, Laboratory Safety Committee

Montreal Neurological Institute

Slides adapted from: Mr. Wayne Wood, Manager ,

Environmental Health and Safety, McGill University

and

Howard Hughes Medical Institute, Online Safety Course

http://www.practicingsafescience.org/


Organization of the presentation

MODULE 1: General Laboratory Safety

Getting Ready to Work

Working in the Lab

Emergency Response

Individual Protection

Chemical Hoods

Biosafety Cabinets

Tissue Culture

Using Autoclaves

Chemical Storage

Leaving the Lab

MODULE 2: WHMIS

Classification of Products

Main Elements of WHMIS

Labels

MSDS

Organization of the Presentation

You are expected to be familiar with the information on the website of McGill Environmental Health and Safety (EHS) http://www.mcgill.ca/ehs/

Additional resources are listed on the website for the MNI Laboratory Safety Committeehttp://www.mni.mcgill.ca/


Slides adapted from mr wayne wood manager

MODULE 1: GENERAL LABORATORY SAFETY

All personnel must be aware of general occupational health and safety issues and procedures, have read the safety manuals applicable to their work, and completed the required training.

Laboratory Safety Manual

http://www.mcgill.ca/ehs/laboratory/labsafety/

Biosafety Manual

http://www.mcgill.ca/ehs/laboratory/biosafety/

Radiation Safety Manual

http://www.mcgill.ca/ehs/radiation/manual/

Consult your supervisor to determine the training required in your laboratory.


Before lab work get to know

Before Lab Work, Get to Know:

  • Hazards of materials & agents and their prescribed safety procedures

  • Proper and safe use of all equipment

  • First get ready, then get to work!


Also get to know

Also Get to Know:

  • Emergency spill procedures, use of adsorbents and disinfectants

  • General Emergency Procedures for your Institution

  • Designated escape route and alternate

  • Location of fire extinguishers, eye wash, shower, first aid, and spill kits


Before lab work get to know1

Before Lab Work, Get to Know:

  • Emergency telephone numbers and reporting procedures

    For all emergencies call:

55-555


While working in the lab

While Working in the Lab:

  • Authorized persons only

  • Identify EVERYTHING!

  • No food, beverages, tobacco products, or application of cosmetics

  • Follow Good Laboratory Practices

  • Practice Safe Science


Weekly monthly lab checks

Weekly/Monthly Lab Checks

Download file: MNI laboratory safety inspection checklist.xls from MNI website

  • Fume Hoods/Biosafety Cabinets

  • Tubing, pressurized connections

  • Chemical storage

  • Cleanliness & Orderliness

  • Eye wash (purge)

  • Fire extinguisher

  • First Aid Kits


Evaluating lab hazards

Evaluating Lab Hazards

  • Regular review of the types of hazards:

  • chemical

  • physical

  • biological

  • ergonomic

  • mechanical

Minor Variation in Procedure


Slides adapted from mr wayne wood manager

Causes of injury in laboratories


Slides adapted from mr wayne wood manager

While Working in the Lab:

  • Report all:

  • Accidents

  • Injuries

  • Fires

  • Spills

  • Close calls

  • Malfunctioning equipment

  • Safety hazards

1

Disabling injury

10

Minor injuries

30

Property damage incidents

600

Close Calls


Emergency response

Emergency Response

When you take a job in a new laboratory, one of the first things you should do is ask your supervisor to review with you the emergency response plans for the lab. Make particular note of the locations of:

  • Emergency telephone numbers.

  • Eyewash fountains and emergency showers.

  • Spill kits.

  • Fire extinguishers.

  • Emergency exits and evacuation routes.


Slides adapted from mr wayne wood manager

Fire

  • Fire is the most potentially devastating emergency in the modern biology laboratory. It is imperative that you know how to prevent fires and be prepared to respond should a fire occur.

  • Preventing fires. Use of flammable solvents is a primary cause of lab fires. Always follow these prudent practices:

    • Use the smallest quantities of flammable solvents as practical.

    • Store stock quantities in flammables storage cabinets.

    • Separate flammable solvents from sources of ignition.Never use a Bunsen burner in any area where flammable solvents are handled.


Emergency response to fire

Emergency Response to Fire

  • Know the fire emergency response procedures of your laboratory and institution procedures of your laboratory.

  • Keep the lab aisles and evacuation routes free of equipment and other objects that could obstruct safe passage. Remember: Safe passage is for your benefit and for the benefit of emergency responders.

  • Periodically practice emergency response procedures.

  • Follow these immediate procedures in case of a major lab fire:

    • Alert people to evacuate the area.

    • Activate nearest fire alarm or call for emergency response.

    • Assess the situation: Only if it is safe to do so, try to extinguish the fire.

    • Close lab doors to confine fire.

    • Have a person who is knowledgeable about the lab and the incident ready to assist emergency personnel.


While working in the lab individual protection

While Working in the Lab:Individual Protection

  • Shoes with full coverage and good grip soles (no sandals)

  • Restrain long hair, loose clothing and jewelry

  • Wear a lab coat

  • Use appropriate eye, skin, and hand protection

  • Wash hands often


Slides adapted from mr wayne wood manager

Howard Hughes Medical Institute: Online Safety Course

http://www.practicingsafescience.org/

I'm here to help you load that TFA into the centrifuge. Oops! I forgot my eye protection. I have to go get it.

  • Well RUN for Pete's sake. Time is money! 

  • Eye protection? You don't need any eye protection. 

  • Okay. Take your time and be aware of your surroundings. It'd be ironic if you were to cause an accident by trying to avoid an accident, wouldn't it?

Think ahead and plan your moves. Be careful of your surroundings.


Eye protection

Eye Protection

  • Protects against risk of flying objects or dust particles, splashes of hazardous materials or harmful rays


Safety glasses

Safety Glasses

  • Unbreakable lenses of plastic or tempered glass

  • For light-to-moderate work

  • Can be prescription lenses

  • Do not interfere with contact lenses


Goggles

Goggles

  • Work with significant risk of splash of chemicals or projectiles

  • Can be worn over prescription glasses


Face shield

Face Shield

  • Work with significant risk of splash on face or possible explosion (including removing vials from liquid nitrogen)

  • Face shield protects face adequately but not eyes


Hand protection

Hand Protection

  • Protects against risk of cuts, abrasions, burns, or exposure to hazardous materials.

  • Requires selection of the appropriate chemical resistant gloves

  • Change gloves often – none are impermeable!

  • Wash your hands often to reduce contamination of yourself and others.

  • Do not touch door knobs, telephones, etc. with gloves – remove them.

  • If you must transfer your experiment to another room

    • put all materials, including clean gloves, in a tray with spill-proof edges

    • remove gloves and wash hands

    • Re-glove once you are in the alternate location


While working in the lab1

While Working in the Lab:

  • Follow universal precautions

  • Handle unknowns as if they were hazardous


While working in the lab2

While Working in the Lab:

  • Handle volatiles, aerosols or fine powders in a chemical fume hood

Contain bioaerosols in a biological safety cabinet


Laboratory chemical hoods

Laboratory Chemical Hoods

  • The laboratory chemical hood is a ventilated enclosure that protects you from being exposed to chemical fumes, gases, and aerosols that are generated within the enclosure. Protection is provided by room air that is drawn into the hood and vented to the atmosphere. The hood ventilation provides further protection by diluting the concentration of flammable gases below explosion limits.

  • The sash must be lowered to the operating position or vapours will spill out.

  • The hood should always be on. Notify the facility staff or the safety office immediately if the hood is off or you observe contaminants escaping from it.


Using laboratory chemical hoods

Using Laboratory Chemical Hoods

  • Plan your experiment. First, assess the risks of your experiment. If a laboratory chemical hood is required, place everything you need in the hood before starting.

  • Lower the sash. Always make sure the sash is pulled down to the marked level. The best protection is provided when the sash is brought to the lowest level for convenient operation.

  • Watch your activity. Use slow and deliberate motions. Place supplies so that they do not obstruct the airflow at the airfoil sill or the exhaust slots at the back of the hood. Do not work within four inches of the airfoil sill.

  • Keep the work area uncluttered. Do not store chemicals in the cabinet.


Storage of hazardous chemicals

Storage of Hazardous Chemicals

  • Laboratory directors, managers and personnel are responsible for understanding the general principles governing storage of the various classes of chemicals and for complying with McGill’s policy. This includes segregation of incompatible chemicals, proper storage conditions (e.g., safety cabinets) and limits on volumes of certain chemicals that may be stored in the laboratory (e.g., flammable liquids).

  • See http://www.mcgill.ca/ehs/laboratory/labsafety/#3.6.3.1

    • Section 4. Handling and Storage of Laboratory Chemicals;

    • Section 7. Laboratory Ventilation And Fume Hoods

    • Appendix 1: Flammability Classification (NFPA) and Permissible Container Sizes (OSHA)


Chemical storage

Chemical Storage

  • Storage areas for corrosive, toxic, flammable, and highly reactive chemicals should be near a laboratory chemical hood.

  • Transfer hazardous chemicals from stock containers to use containers only in a laboratory chemical hood.

  • You should not store hazardous chemicals inside the hood.


Rules of thumb for safe storage

Rules of Thumb for Safe Storage

  • Do not store more chemicals than you will need over a reasonable time

  • Always read the chemical's label and mark it with the date of receipt before storing.

  • Never store highly reactive chemicals for longer than 6 months.

  • Never store a chemical with an obscured or missing label.

  • Separate chemicals into compatible groups and store alphabetically within the groups (see section 4 of lab safety manual).

  • Designate separate storage areas for highly toxic chemicals.

    • Flammables, organic acids and organic bases in separate trays in a flammables’ cabinet

    • Inorganic acids, strong bases in separate trays in the cabinet under the fume hood

    • Toxic chemicals separately.

    • Oxidizers separately.

    • Corrosives separately.

    • Dry chemicals on shelves with raised edges, separated according to incompatibility.

  • Flammables should never be stored in a frost-free refrigerator/freezer.


Class ii biosafety cabinets

Class II Biosafety Cabinets

  • The type of hood present in most tissue culture labs.

  • Protects you from being exposed to infectious aerosols that may be generated within the cabinet. You are protected by room air that is drawn into the cabinet front grill and the cabinet downward airflow. This combination of airflows quickly prevents respirable size particles from escaping into your lab.

  • Protects your cultures from microbialcontaminants that are ubiquitous in roomair. Your cultures are protected by the cabinet downward airflow, which is filtered by high efficiency particulate air (HEPA) filters. HEPA filters also treat cabinet exhaust air.


Working in a biosafety cabinet

Working in a Biosafety Cabinet

  • Use personal protective equipment

    • Wear a lab coat and gloves.

  • Plan your experiment in advance

    • Place everything you need in the cabinet or on an adjacent cart before starting the experiment.

    • Designate separate areas on the cabinet work surface for clean materials and dirty materials.

    • Check that the vacuum bottle contains fresh disinfectant (e.g., a one-in-ten dilution of household bleach) and that there is enough space to collect all waste.

    • Do not use solvents in the presence of open flame.


Working in a biosafety cabinet1

Working in a Biosafety Cabinet

  • Use careful, sterile technique!

    • Work with the sash lowered to the indicated level.

    • Move slowly and deliberately with planned movements.

    • Do not pass your hands over sterile preparations or containers.

    • Discharge pipettes against the flask or tube wall to avoid splashes.

    • Do not re-introduce pipettes into stock containers – use another pipette.

    • Place disposable pipettes and dishes into biohazard containers and non-disposables into disinfectant.


Working in a biosafety cabinet2

Working in a Biosafety Cabinet

  • Wash hands before and after procedure. If gloves become soiled, remove them, wash hands and put on new gloves.

  • Be careful of sharps!

  • Clean up at the end of the procedure and disinfect surfaces with alcohol.

  • Before leaving the room, check everything! Then check again!


How to avoid contaminating your cultures you or your coworkers

How to Avoid Contaminating your Cultures, You or your Coworkers

  • Cleanliness!!

    • You

      • Wash your hands before and after any procedure

      • Avoid touching telephones, door knobs, equipment with gloved or dirty hands

    • Incubators

      • Wash and disinfect thoroughly on a regular basis

      • Clean up spills immediately

      • Check for contaminated cultures regularly and remove immediately

    • Biosafety Cabinets

      • Keep free of clutter, particularly to maintain airflow

      • Keep surfaces clean and disinfected

      • Clean under the working surface regularly

    • The Room

      • Keep counters, floors and equipment clean and uncluttered

      • Do not overfill biohazard containers

      • Keep traffic to a minimum and have an organized schedule of use

  • Organization and Sterile Technique

    • Proper technique eliminates the need for routine use of antibiotics – save them for when you really need them.


Using autoclaves

Using Autoclaves

  • Load the autoclave according to instructions. Do not use without prior instruction.

  • Use loading racks/trays – never place any item directly on the bottom or floor of the autoclave.

  • Starting the sterilization cycle. Make sure the door of the autoclave is fully closed and the correct cycle has been selected before starting the sterilization cycle.

  • Unloading the autoclave. Protect yourself from steam and heat by wearing heat-resistant gloves. First, slightly crack open the door. Wait a full five minutes if the autoclave load contains just glassware, and no less than ten minutes when you are autoclaving liquids. Then remove the load and let the glassware stay on the racks 15 minutes before handling the individual pieces.


Autoclaving liquids

Autoclaving Liquids

  • Loosen caps. Before loading containers of liquids into the autoclave, the caps must be loosened to avoid having the bottles shatter.

  • Guard against spills. Use a tray with a solid bottom and walls to contain bottles and catch any spills. Add a quarter to a half-inch of water so the bottles will heat more evenly.

  • Unload with extreme caution. Always wear a rubber apron in addition to your standard protective equipment when removing bottles that contain liquids from the autoclave. Be alert for a bottle still bubbling - it could explode easily if touched. Let the load stand in an out-of-the-way place for a full hour before handling.


Before leaving the lab

Before Leaving the Lab:

Turn off:

  • Gas

  • Water

  • Power supplies

  • Vacuum lines

  • Compression lines

  • Heating apparatus


Before leaving the lab1

Before Leaving the Lab:

  • Identify and package waste, dispose properly

  • Put away experimental apparatus, chemicals, etc.

  • Lock/out and tag/out defective equipment

  • Decontaminate work surfaces and equipment


Before leaving the lab2

Before Leaving the Lab:

  • Return borrowed equipment, apparatus, etc.

  • Leave lab coat in the lab

  • Wash

  • Close and lock door


Before leaving the lab3

Before Leaving the Lab:

  • Clean up your mess

  • Leave the lab safe for everyone

  • Perform a final check!!!


Module 2 workplace hazardous materials information system whmis

MODULE 2Workplace Hazardous Materials Information System (WHMIS)

http://www.hc-sc.gc.ca/hecs-sesc/whmis/msds.htm


Slides adapted from mr wayne wood manager

“No employer may allow the use, handling or storage of a Controlled Productin a workplace unless the product carries a label and a material safety data sheet which meet the requirements of this Act and the regulations and unless the worker has received the training and information required to carry out the work entrusted to him safely”- Article 62.1, An Act respecting occupational health and safety R.S.Q., S-2.1


What are controlled products learn the universal symbols for each class

What are Controlled Products?Learn the universal symbols for each class

Class A:

Compressed Gas

Class B:

Flammable and Combustible Material


Controlled products

Controlled Products

Class C:

Oxidizing Material


Class d controlled products

Class D Controlled Products

Division 1:

Materials Causing Immediate and Serious Toxic Effects

Division 2:

Materials Causing Other Toxic Effects

Division 3:

Biohazardous Infectious Materials


Controlled products1

Controlled Products

Class E:

Corrosive Material

Class F:

Dangerously Reactive Material


Not classified as controlled products

Not Classified as Controlled Products:

explosives

radioactive

materials


Consult the mcgill laboratory safety manual

Consult the McGill Laboratory Safety Manual

  • Learn how to store each class of chemical and separate incompatible classes of chemicals

  • Learn the limits on storage of hazardous chemicals in the laboratory (e.g., flammable liquids)

    http://www.mcgill.ca/ehs/laboratory/labsafety/#3.6.3.1


Class a compressed gas characteristics

Class A: Compressed GasCharacteristics

  • Gas inside cylinder is under pressure

  • The cylinder may explode if heated or damaged

  • Sudden release of high pressure gas streams may puncture skin and cause fatal embolism


Class a compressed gas precautions

Class A: Compressed GasPrecautions

  • Transport and handle with care

  • Make sure cylinders are properly secured

  • Store away from sources of heat or fire

  • Use proper regulator


Class b flammable and combustible material characteristics

Class B: Flammable and Combustible MaterialCharacteristics

  • May burn or explode when exposed to heat, sparks or flames

  • Flammable: burns readily at room temperature

  • Combustible: burns when heated


Class b flammable and combustible material precautions

Class B: Flammable and Combustible MaterialPrecautions

  • Store away from Class C (oxidizing materials)

  • Store away from sources of heat, sparks and flame

  • Do not smoke near these materials


Class c oxidizing material characteristics

Class C: Oxidizing MaterialCharacteristics

  • Can cause other materials to burn or explode by providing oxygen

  • May burn skin and eyes on contact


Class c oxidizing material precautions

Class C: Oxidizing MaterialPrecautions

  • Store away from Class B (flammable and combustible) materials

  • Store away from sources of heat and ignition

  • Wear the recommended protective equipment and clothing


Class d division 1 materials causing immediate and serious toxic effects characteristics

Class D, Division 1Materials Causing Immediate and Serious Toxic EffectsCharacteristics

May cause immediate death or serious injury if inhaled, swallowed, or absorbed through the skin


Class d division 1 materials causing immediate and serious toxic effects precautions

Class D, Division 1Materials Causing Immediate and Serious Toxic EffectsPrecautions

  • Avoid inhaling gas or vapours

  • Avoid skin and eye contact

  • Wear the recommended protective equipment and clothing

  • Do not eat, drink or smoke near these materials

  • Wash hands after handling

  • Follow procedures for disposal of chemical waste


Class d division 2 materials causing other toxic effects characteristics

Class D, Division 2Materials Causing Other Toxic EffectsCharacteristics

  • May cause death or permanent injury following repeated or long-term exposure

  • May irritate eyes, skin and breathing passages: may lead to chronic lung problems and skin sensitivity

  • May cause liver or kidney damage, cancer, birth defects or sterility


Class d division 2 materials causing other toxic effects precautions

Class D, Division 2Materials Causing Other Toxic EffectsPrecautions

  • Avoid inhaling gas or vapours

  • Avoid skin and eye contact

  • Wear the recommended protective equipment and clothing

  • Do not eat, drink or smoke near these materials

  • Wash hands after handling

  • Follow procedures for disposal of chemical waste


Class d division 3 biohazardous infectious material characteristics

Class D, Division 3Biohazardous Infectious MaterialCharacteristics

Contact with microbiological agents (e.g., bacteria, viruses, fungi and their toxins) may cause illness or death


Class d division 3 biohazardous infectious material precautions

Class D, Division 3Biohazardous Infectious MaterialPrecautions

  • Wear the recommended protective equipment and clothing

  • Work with these materials in designated areas

  • Disinfect area after handling

  • Wash hands after handling


Class e corrosive material characteristics

Class E: Corrosive MaterialCharacteristics

  • Will burn eyes and skin on contact

  • Will burn tissues of respiratory tract if inhaled

7


Class e corrosive material precautions

Class E: Corrosive MaterialPrecautions

  • Store acids and bases in separate areas

  • Avoid inhaling these materials

  • Avoid contact with skin and eyes

  • Wear the recommended protective equipment and clothing


Class f dangerously reactive material characteristics

Class F: Dangerously Reactive MaterialCharacteristics

  • May be unstable, reacting dangerously to jarring, compression, heat or exposure to light

  • May burn, explode or produce dangerous gases when mixed with incompatible materials


Class f dangerously reactive material characteristics1

Class F: Dangerously Reactive MaterialCharacteristics

  • Store away from heat

  • Avoid shock and friction

  • Wear the recommended protective equipment and clothing


Other important universal signs

Other Important Universal Signs


What do these symbols mean

What do these symbols mean?


Whmis main elements

WHMIS Main Elements

Labels

  • - supplier

  • - workplace

  • - laboratory

Material safety data sheets

- supplier

- workplace

DIMETHYL

MEGADEATH

  • Training

    • - core

    • - job specific


Supplier s label learn how to read them

Supplier’s LabelLearn how to read them

TOLUENE SULFONIC ACID

PRODUCT IDENTIFIER

RISK PHRASES:

Highly irritating to skin, eyes, and nose

HEALTH HAZARD DATA:

Strong Acid: Treat as sulphuric acid

EFFECTS OF OVEREXPOSURE: ACUTE

ABC Chemicals

123 Chemical Drive

Chemical City

1-800-CHE-MICAL

Supplier

identifier

PRECAUTIONARY MEASURES:

PERSONAL PROTECTIVE EQUIPMENT

EYE: Face shield and goggles

GLOVES: Rubber

OTHER CLOTHING AND EQUIPMENT: Rubber apron, rubber boots

FIRST AID:

EYES: Flush with water for 15 minutes. Consult with physician

SKIN: Flush with water as per sulphuric acid

INGESTION: Treat as per sulphuric acid. Consult with physician

Refer to Material Safety Data Sheet

FRANCAIS AU VERSO


Workplace labels required

Workplace Labels Required:

  • On controlled products produced and used in the workplace,

  • if the label becomes illegible.

  • received from a supplier and transferred to another container*

*not required if transferred material is used in its entirety prior to the end of the work shift


Workplace labels in research labs

Workplace Labelsin Research Labs

  • Product identifier (name)

  • MSDS must be available in the lab

Agent Green


Material safety data sheets

Material Safety Data Sheets

  • Supplier must provide

  • Accessible to ALL workers in the workplace

  • Must be kept up to date

  • Must be made available to doctor in the event of exposure


What s in an msds

What’s in an MSDS?

Product Information

Item Name

Company's Name

Emergency Phone #

Part Number

MSDS Preparation

Ingredients


What s in an msds1

What’s in an MSDS?

Physical Properties

Appearance and Odor

Volatility

Solubility

pH

Fire and Explosion Data

Extinguishing Media

Flash point

Special Fire Fighting Procedures

Unusual Fire And Explosive Hazards


Definition flash point

Definition: Flash Point

  • The flash point is the lowest temperature at which a liquid produces enough vapour to ignite in the presence of a source of ignition.

  • The lower the flash point, the greater the risk of fire.


What s in an msds2

What’s in an MSDS?

Product Reactivity

Stability

Conditions To Avoid

Materials To Avoid

Hazardous Decomposition Products

Hazardous Polymerization?

Toxicological information

LD50-LC50

Route Of Entry

Signs/Symptoms Of Overexp

Carcinogenicity


Definition threshold limit value

Definition: Threshold Limit Value

  • TLV (TWA) is an 8-hour time-weighted average believed to be the average concentration to which most workers can be exposed during an 8-hour workday, day after day, without harmful effects.

  • TLV (STEL) is a 15 minute “short term exposure limit”

  • Ceiling (C) is a maximum concentration never to be exceeded

Daily exposure

limit


Definition lc50

Definition: LC50

  • LC50 (Lethal Concentration50) is the amount of a substance in air that, when given by inhalation over a specified period of time, is expected to cause the death in 50 per cent of a defined animal population.


Definition ld50

Definition: LD50

  • LD50 (Lethal Dose50) is the amount of a substance that, when administered by a defined route of entry (e.g. oral or dermal) over a specified period of time, is expected to cause the death of 50 per cent of a defined animal population.


What s in an msds3

What’s in an MSDS?

Preventive measures

Respiratory Protection

Protective Gloves

Eye Protection

Other Protective Equipment

Ventilation

Storage

Spills

First Aid Measures


Slides adapted from mr wayne wood manager

  • Which one of the following two procedures presents the greater risk of producing a harmful effect?Procedure 1: A technician handles 0.26 ml of ethyl methanesulfonate (EMS) in preparing 100 ml of EMS sucrose solution needed for mutagenesis studies with flies. The technician performs this procedure once every three months. EMS is a possible human carcinogen. The oral LD50 for EMS is 470 mg/kg in mice, a moderately toxic rating.Procedure 2: A technician prepares agarose gels daily. The concentration of ethidium bromide in the gel box is 5 µg/ml. Ethidium bromide is a powerful mutagen though its effects on humans are unknown. The reported subcutaneous LD50 in mice in one study was 100 mg/kg, a moderately toxic rating.

  • Procedure 1 presents the greater risk of producing a harmful effect.    

  • Procedure 2 presents the greater risk of producing a harmful effect.    

  • The risks associated with procedures 1 and 2 are about the same.

    Answer on next slide:


Slides adapted from mr wayne wood manager

  • Answer 2 presents the greater risk because the agent is used daily rather than every three months.


Controlled products characteristics and precautions

Controlled Products - Characteristics and Precautions


Nfpa labels national fire protection association

NFPA labels (National Fire Protection Association)

  • Also valuable is the National Fire Protection Association's labeling system that shows the type and the degree of a chemical hazard.

  • The labels are commonly included on chemical containers.

  • The labels are diamond-shaped and color-coded.

    • Blue indicates the health hazard.

    • Red indicates the fire hazard.

    • Yellow indicates the reactivity hazard.

    • White gives special information such as water or oxidizer incompatibility.

  • In each field, the degree of the hazard is rated from 0 to 4, with 4 being the greatest hazard and 0 indicating no significant hazard.

  • Thus you can see at a glance particular hazards associated with storage or use of the chemical. You must also consult the MSDS safety data sheet.


Slides adapted from mr wayne wood manager

Risk AssessmentAny experiment involving a toxic chemical requires planning to help you determine the potential risks and to aid in the selection of safe practices.

  • Identify chemicals to be used.

  • Identify circumstances of use.

  • Consult sources of information.

  • Evaluate chemical toxicity.

  • Consider possible routes of exposure.

  • Select appropriate safety practices.

  • Prepare for contingencies.


Final words

Final Words

Safety is YOUR RESPONSIBILITY

Get the proper training

If you don’t know or are unsure, then ASK


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