Teaching Science Safely

1
Teaching Science Safely

• Three Teacher Responsibilities
• Science Safety References
• Physical Hazards
• BSC and CHE Safety Measures
• Risk Management
• Safety Guidelines for Labs, Classrooms, and
  Storage Areas

2
Three Teacher Responsibilities(per Council of
State Science Supervisors)

• Duty of instruction
• Ensure adequate instruction before activity
• Identify and clarify risks involved
• Provide proper procedures
• Duty of supervision
• Misbehavior not tolerated failure to act
  problematic
• Greater danger requires greater supervision
• Never leave students unsupervised
• Duty of maintenance
• Maintain safe environment
• Maintain safe equipment

3
NSTA Safety Guidelines
Dean, R. A., Dean, M. M., Motz, L. L. (1978).
Safety in the Secondary Science Classroom,
Washington, DC NSTA Subcommittee on Safety.
4
School Personnel Responsibilities

• Principal - general classroom conditions two
  exits from lab appropriate heat and light
  burn-resistant tables master shutoffs on gas,
  electricity and water grounded electrical
  outlets fume hoods storage areas fire
  extinguishers shower etc.
• Departmental chairperson - safety meetings
  notify principal in writing of safety concerns
  safety supplies safe storage of materials
  safety inspections safety rehearsals
  non-accumulation of waste properly qualified
  teachers etc.
• Science teacher - instruct students in safety
  matters warn students of hazards develop and
  use a student safety contract post safety
  regulations provide for required safety
  materials such as eye protection care and
  handling of animals and hazardous materials,
  proper use of fire extinguishers safety
  procedures, etc.

5
Safety in the Science Classroom

• The Safety Program
• school personnel safety responsibilities
• suggestions for a safe science program
• OSHA v. Illinois Life-Safety Code
• Safety Procedures (for example)
• first aid
• eye protection
• glassware
• health hazards
• Laboratory Safety
• electronic equipment
• rockets, etc.

6
AAPT Guidelines for Physics
Peterson, R. W. (1979). Teaching Physics Safely,
Washington, DC AAPT Committee on Apparatus.
7
Safety Physics

• Electrical
• Lasers and Light
• Pressurized Vacuum Systems
• Ionizing Radiation
• Fires
• Toxic Materials
• Mechanical

8
Electrical

• Effects 60 Hz DC
• perception 1 ma 5 ma
• loss of control 10 ma 70 ma
• respiratory failure 25 ma 80 ma
• ventricular fibrillation 100 ma 100 ma
• Dry skin resistance
• 100,000 to 500,000 ohms / square centimeter
• resistance reduced by wetness or sweat
• resistance reduced by puncture wounds
• Completed circuits to watch out for
• hand to hand
• hand to ground

9
Lasers and Light

• Never permits students to look into a direct or
  specularly reflected laser beam.
• Use beam splitters or neutral density filters to
  reduce the intensity of a laser beam.
• Supervise students closely.
• Transmission holograms are to be viewed with a
  beam which is greatly expanded.
• Experiments utilizing laser light should not be
  set up at eye level.
• It is preferable to observe projected images
  rather than looking directly into a laser beam.
• Be careful with UV (conjunctivitis).

10
Pressurized Vacuum Systems

• Gas cylinders must be safely secured and used
  with a regulator.
• Bell jars and coin-feather tubes and prone to
  implosion.
• Never pressurize or evacuate items not designed
  for such.
• Use a clear screen shield and safety glasses to
  shelter students from harm. Where a screen is not
  desirable, wrap items with strong tape.
• Use high quality dewars, not cheap thermos
  bottles which might explode from leakage.
• Avoid damage due to cold (N2 -196oC)

11
Ionizing Radiation

• Ionizing radiation consists of alpha, beta, and
  gamma particles, neutrons, and X rays.
• In general
• Quantity -- use the smallest amount avoid direct
  contact by use of tongs, etc.
• Shielding -- a 1-cm layer of Plexiglas will stop
  high energy beta particles lead is needed for
  gamma or X rays
• Radiation is endemic, but relatively safe in
  small doses

12
Fires

• Reduce likelihood of fire.
• Watch out for open flames.
• Watch out for flash points of liquids and high
  concentrations in air which might explode.
• ethyl alcohol, methyl alcohol, acetone, gasoline,
  benzene, carbon disulfide vapors sink and
  accumulate near floor
• Know how to handle types of fires
• Class A (wood, paper, cloth) Class B (fats,
  oils, solvents) Class C (electrical) Class D
  (metals)
• Have emergency materials on hand.
• fire blanket or sand
• fire extinguisher (ABCD)

13
Toxic Materials

• Solids, liquids, gases
• Mercury, certain metals, asbestos
• benzene and carbon tetrachloride
• caustic liquids (strong acids and bases)
• carbon dioxide and carbon monoxide
• Material Safety Data Sheets (MSDS)
• Visit the National MSDS Repository NMSDSR

14
Mechanical

• projectiles
• falling objects
• moving equipment
• powerful permanent magnets

15
In the event of an accident

• Be prepared with a good safety plan.
• Act quickly, correctly, and decisively
• Remove hazard and prevent further harm.
• Check with injured party about extent of injury.
• Decide on an appropriate course of action.
• Notify school authorities and/or call 911 as
  necessary.
• Have properly trained individual care for injured
  party.
• Notify parent, guardian, or designated alternate
  person.
• After event subsides
• Make permanent record of the event
• Obtain eyewitness reports
• Provide copies to administration
• Keep your records in a safe and secure place.

16
Biology Chemistry Teaching

• As a student in an NSTA-accredited program with
  broad field preparation you are required to
  understand the connection between science and
  safety for all disciplines
• You must complete a Legal and Safety Concerns
  online test at a gt 90 performance level.
• Read Science and Safety Making the Connection
  SS
• Here is a brief overview of what you need to
  know

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Table of Contents (short list)

• Where can I find a general science-safety
  checklist?
• How should I label and store chemicals?
• How should I purchase new chemicals and dispose
  of old chemicals?
• What should a chemical hygiene checklist for
  school science labs include?
• What precautions should I take when using animals
  or plants in the laboratory?
• What protective equipment should be kept/provided
  in a laboratory for teacher and student use?
• Are there recommended checklists covering the
  physical layout/specifications of science labs?

18
Safety Biological Sciences 1

• Animals - prevent abuse and neglect
• Watch out for student allergies
• Handle animals only after proper handling
  instructions
• Gloves and hand washing a good idea
• Report bites and scratches
• Have vet examine animals that die unexpectedly
• Never put fecal matter down the drain
• Never use wild animals
• Never use poisonous animals
• Never allow students to tease animals or touch
  animals to their mouths.

19
Safety Biological Sciences 2

• Plants - many produce toxic substances
• Watch out for student allergies
• Never use poisonous or allergy-causing plants in
  room
• Never burn plans that might contain
  allergy-causing oils
• Make a clear distinction between edible and
  non-edible plants
• Never allow plants to be tasted without clear
  direction from teacher
• Have students wear glove or wash hands after
  handling.

20
Safety Chemistry 1

• Labeling chemicals
• Manufacturer or supplier (including address and
  phone number)
• Chemical and/or trade name - same as MSDS
• Date received or placed in container
• Strength of the chemical
• Handling and/or mixing precautions
• Appropriate hazard symbol National Fire
  Protection Association (NFPA) rating

21
Safety Chemistry 2

• Storing chemicals
• Keep storage separate from the classroom
• Be certain storage area is properly ventilated
• Fire door or exits must be provided
• Provide for proper extinguishing systems
• Shelving must be secured to the wall
• Separate organic from inorganic chemicals
• Properly separate incompatible chemical families
• Make certain chemicals in appropriate containers
• Store flammables and corrosives separately

22
Safety Chemistry 3

• Acquisition and disposal of chemicals
• Limit acquisitions to needs for 1-2 years
• Be certain you can store, use, and dispose of
  chemical safely before ordering
• Be certain you have proper personal protective
  equipment for working with the chemical
• Be certain everyone aware of any hazards
  associated with chemical
• Be certain that everyone who might handle
  chemical is properly trained to do so
• Be certain that budget allows for disposal of
  chemical and/or any by-products.
• Use safe and approved disposal methods

23
Safety IL School Law Code

• What safety requirements are contained in the
  Illinois School Law Code to protect persons on
  school property from injury?
• Every student, teacher, and visitor must wear an
  industrial quality eye protective device when
  working in chemical or combined chemical-physical
  laboratories involving caustic or explosive
  chemicals or hot liquids or solids.

24
Risk Management

• 1) Determine the nature of the risks before
  conducting any potentially hazardous activity.
• 2) Mitigate potential hazards and damage.
• 3) Determine what hazards remain.
• 4) Examine the benefit-to-risk ratio, r.
• If r gtgt 1, then it is prudent to perform the
  activity in question.
• If r lt 1, then it probably is not prudent to
  perform the activity in question.

25
Safety Guidelines for Labs

• Student Safety Contract
• Thou shall....
• Thou shall not....
• Do this during the first day or two of class, but
  certainly before the first lab
• Be prepared with a detailed Safety Plan
• A detailed Safety Plan will be required of you
  for your student teaching site.