Chapter 2 Lecture 1

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Chapter 2: Emergency Response
A. Section 2.1.1 Responding to Laboratory Emergencies
1.
2.
Incident 2.1.1.1 Sulfuric Acid Spill
Emergencies Requiring Evacuation—fires and chemical spills
a. Introductory Labs generally use small amounts of chemicals, so evacuation is rare
b. Likely response is to panic when confronted with a fire or large chemical spill
i. Take a moment to calm down
ii. Then decide how to respond
3. When Do You Need to Leave?
a. If a fire alarm goes off in a laboratory building (especially), get out
b. If the emergency happens near to you
i. Call out loudly to let others near you know of the danger
ii. Must decide to deal with it or to leave
c.
d.
iii. If you decide to leave, make sure you notify someone in charge quickly
- Teaching assistant, instructor, other faculty, or staff member
- Turn off gas and/or burners; Call 911 if no one found to notify
iv. Don’t put yourself at unnecessary risk—professional responders will help
Priorities in a hazardous situation:
i. Life Safety
ii. Minimize property loss
iii. “Everybody goes home” is the motto of the US Fire Service
iv. No one should ever die trying to save a building
Other considerations
i. Pull fire alarm?
- Generally near main exits and/or stairwell doors
- If the smoke or flame is too heavy, don’t put yourself at risk to do this
- May not alert fire department, so go ahead and call 911 also
ii. Know where the exits are!
- Not just for laboratory buildings, but any building you go into
- True for hotels, movie theaters, airplanes, etc…
- Sometimes nearest exit is not the one you entered from
iii. Is there a predetermined meeting place? Did someone you know get left?
iv. Don’t go back in until given the all clear by emergency personnel.
4. Mitigating the Emergency
a. Sometimes, quick action by a student can prevent a fire/spill from becoming worse
b. We will specifically discuss these actions later
c. Don’t clean up chemical spills; notify instructor for help
d. Tough choice sometimes if someone is injured and can’t get out themselves
e. Must decide, but becoming a second victim doesn’t help anyone
5. Non-Laboratory Related Emergencies (SWOSU Alert System)
a. Some emergencies cause you to seek shelter, rather than to evacuate
i. Tornadoes and other storms
ii. Usually designated “shelter-in-place” locations
- Hallways, Basements, Stairwells, Closets
- Avoid windows and glass doors
iii. Should be aware of where to go prior to the emergency
iv. May need to assist people with disabilities; if you can’t help, notify responders
b. Police Emergencies (SWOSU Procedure)
i. Follow instructions from law enforcement
ii. Universities may have protocols to follow; faculty should know the plan
iii. Turn off laboratory equipment, gas, heaters, etc… before you leave
c. Electrical Outages: turn off equipment anyway; cap bottles in hoods if you can
B. Section 2.1.2 Fire Emergencies in Introductory Labs
1.
Incident 2.1.2.1 Fire from Frayed Electrical Wiring
2.
Dangers of Fires in Laboratories
a. Burns and destruction as in “normal fires”
b. Burning chemicals can produce toxic fumes
c. Some chemicals may be explosive
d. Worst Case Scenario not very likely in Introductory Labs
e. Knowing what kind of fire you are facing makes it more likely you can put it out
3.
Classes of Fires
a. Class A Fires
i. Most common fire in non-laboratory situations—burning house or business
ii. Most easily extinguished with water
iii. Not always the type of laboratory fire
iv. Most labs don’t use water fire extinguishers
b. Class B Fires
i. Burning Organic Liquids—gasoline, acetone, ethers, etc…
ii. Common in Organic Chemistry and sometimes Introductory labs
iii. Water does not mix with these liquids, so is not very effective
iv. A stream of water might just splash the solvent and spread the fire
c. Class C Fires
i. Any class A or B fire that also involves electricity—burning computer
ii. Water conducts electricity, so you may spread the electrical charge
iii. Never use water on this type of fire
d. Class D Fires
i. “Active Metal” fires
ii. Alkali Metals (sodium, potassium, etc…) react strongly with water
iii. Hot magnesium or aluminum may also ignite with water
e.
Lab fires generally involve Type B and Type C, so we don’t use water to put out
4. The Fire Triangle and Tetrahedron
a. Using the fire triangle to understand how to prevent fires
i. Fuel
ii. Heat or Ignition Source
iii. Oxygen
iv. Fire can’t start with out all three of these
b. Using the fire tetrahedron to understand how to extinguish fires
i. Fuel: wood (A), acetone (B)
- Not always easy to remove
- Moving the fuel or non-burning fuel away from fire can help
ii. Oxygen (or oxidizing agent)
- Almost always O2 gas from air
- Place a beaker over the fire, or Put a lid on a trash can
- Put a book on a burning piece of paper
- Stop, drop, and roll is aiming to remove O2
- Coat with a powder or foam
iii. Heat/Energy
- Keep away from flammables
- Cool with water
iv. Chain Reaction
- Fires are chemical reactions that propagate themselves
- Catalytic Chain Reaction = products cause more reactants to react
- Some fire extinguishers interfere with this process to stop the fire
5. How Fires Burn
a. Solids and Liquids don’t burn, they must be vaporized to gas
b. Flammable vapors combine with gaseous Oxygen to burn
c. Pyrolysis = “pyro = fire” “lysys = breaking down”
i. Bonds are broken and smaller components are given off
ii. The small components are volatile and become the gaseous fuel of the fire
iii. Same process is used to process petroleum to smaller components (but no fire)
e. Momentary cooling may be enough to stop the production of gases and extinguish
the fire (stopping the chain reaction and/or removing the fuel)
i. Works well for class B fires
ii. Solid fuels are often hot enough that momentary cooling doesn’t help
6. Matching Fire Extinguishers and Fires
7. Using Water to Extinguish a Fire
a. Not usually preferred for lab fires, which are often Type B and/or Type C
b. Water works primarily by cooling the burning fuel, stopping gasification, no heat
8. Carbon Dioxide Extinguishers
a. Red, heavy, metal fire extinguisher with a big black cone
b. Works for Class B or Class C fires
c. Filled with liquid CO2, which vaporizes instantly at atmospheric pressure
d. Works by smothering fire (removing Oxygen by surrounding with CO2)
e. This also momentarily cools the fire and reduces vaporous fuel as flame goes out
f. Most liquids have low heat capacities, so they aren’t hot enough themselves
g. If another source of heat is present, however, the solvent might reignite
h. Doesn’t work as well on Class A fires, as solid wood remains hot enough to reignite
i. For Class C fires, you must turn off electricity to keep from reigniting
CO2 Phase
Diagram
9. Dry Chemical Extinguishers
a. BC Dry Chemical Extinguishers
i. Powder that coats the surface of a flammable liquid to eliminate vapor
ii. Extinguishes the fire for lack of fuel
b. ABC Dry Chemical Extinguishers
i. Works like BC
ii. Also forms a sticky solid layer on Class A materials to prevent O2 reaction
10. Choosing a Fire Extinguisher
a. Fire codes require that buildings have the appropriate extinguisher for the most
likely kinds of fire to occur there
b. Most science buildings will have ABC extinguishers
c. Some will have BC and/or CO2 extinguishers—don’t use on Class A fires
d. Dry powder will seriously damage computers/instruments: Use CO2 instead
e. IN REALITY: USE WHATEVER IS THERE!
f. NOTE: Don’t assume a beaker of clear liquid is water—in a lab it may be Class B!
10. Using Fire Extinguishers
a. Nothing substitutes for practice with the real thing
b. All extinguishers are meant to work the same
i. Pull the pin—safety pin prevents accidental activation
- Pin may be secured by plastic tie
- Can break the tie by pulling or twisting the pin
ii. Aim the nozzle or cone at the base of the fire
- Aiming above the fire doesn’t necessarily accomplish the goal
- Small extinguishers have the nozzle right at the top
- Some have a flexible hose, other have a solid pipe that swings up
iii. Squeeze the handle to discharge
- Dry powder extinguishers make a little noise
- CO2 extinguishers make a lot of noise; don’t let it scare you
iv. Sweep the discharge back and forth horizontally over the fire
v. Releasing the squeezed handle will stop the discharge
c. Most extinguishers only last 30 seconds to a couple of minutes
d. Better off using it all up than having the fire reignite (use common sense)
e. Have to know where it is before you can use an extinguisher
i. Fire code requires conspicuous locations—in labs, in hall outside lab, by exit
ii. Whenever you work in a lab, know where the extinguisher is
11. What if you are on fire?
a. Fast response is the best response
b. Burning clothing/skin is a Class A fire
c. Safety showers must be available in all modern labs
i. The water will be cold (this is not a bathroom shower)
ii. You may have to run to the safety shower, it might be a little ways off
iii. Get burning or contaminated clothing off
- Don’t let modesty get you injured worse
- Clear the room for safety and privacy
d. Drench Hoses = long flexible hose coming from a sink in some labs
i. May be an option for small fire
ii. May have eye-wash capability
e. STOP, DROP, and ROLL
i. Still an effective technique
ii. Works best if other pat out the fire on top—use jacket, towel, gloves
f. Covering with a fire blanket also very effective
i. May make worse if they are still standing—chimney effect (knock them down)
ii. Also can use to cover someone after they’ve been under a safety shower
g. Fire extinguisher?
i. May not be for Class A, May also be toxic (but better than nothing)
12. Other Considerations
a. Should you fight the fire yourself? Yes if…
i. It is a small fire (flames floor to ceiling is not a small fire)
ii. You can get the “correct” extinguisher quickly and you know how to use it
iii. You can keep an exit available from the fire at all times
b. What else should you do?
i. Let others (instructor) know what is going on: yell if you need to
ii. Have someone call 911
iii. Get someone to start evacuating the building
iv. Pull the fire alarm if you need to; this is not a prank, the firefighters won’t
mind if you put out the fire before they get there. They can make sure its out.
13. RAMP for Fires:
a. Recognize: organic solvents, electrical equipment, reactive metals
b. Assess: How much is on hand? What are the ignition sources?
c. Minimize: Store flammables and active metals in flammables cabinets. Get frayed
wiring or faulty electrical equipment fixed.
d. Prepare: Know where fire extinguishers, safety showers, exits are located. Know
how to use fire extinguishers and fire alarms.
C. Section 2.2.1 Fire Emergencies in Advanced Labs
1.
Incident 2.2.1.1 Lithium Aluminum Hydride
2.
Incident 2.2.1.2 Solvent Fire
3.
Class B Fires: Organic Liquids
a. Likely to be present in large amounts in Advanced and Research Labs
b. Remember that water is not a good way to fight these fires
c. Chlorinated Solvents are often used in Organic reactions
i. Oxidized C atoms (attached to Cl) are not as flammable as reduced C
ii. Hydrocarbons are very flammable
iii. Chorinated Solvents are not
iv. Halons (Halogenated Hydrocarbons of methane and ethane) were once used as
fire extinguishing agents
v. Damage to the Ozone Layer has greatly reduced their use
Dichloromethane
Chloroform
Carbon Tetrachloride
CAMEO = database of computer programs
used for planning emergency response
NFPA = National Fire Protection
Association
4. Class C Fires: Electrical Fires
a. Usually have Class A materials burning, but were started by electricity
b. Remember not to use water, because you may shock yourself/others
c. ABC Extinguisher is best, but may damage electrical equipment
d. A CO2 extinguisher might work, but not always. Won’t damage equipment
e. Some computer labs and instrument rooms will have their own fire suppression
a. CO2 or some other inert gas displaces the oxygen in the room
b. Won’t harm electronics
c. You might not be able to breathe!
5. What chemicals are used in fire extinguishers?
a. Components
i. Propellant = pressurized gas to push active ingredient out (often N2, CO2)
ii. Extinguishing Agent = material that puts out the fire
b. Dry Chemical Extinguishers
i. ABC = Ammonium Dihydrogen Phosphate = (NH4)H2PO4
- Mildly corrosive combined with water (H3PO4)
- Produces Metaphosphoric Acid Polymer when heated (HPO3)n
- Coats fuel and starves it of oxygen to put out the fire
ii. BC = Sodium or Potassium Carbonate (NaHCO3)
- Cleanup is easier (not corrosive)
- Won’t work on Class A fires
c. Dry Powder Extinguishers for use on Class D fires
i. Sand, Salt (NaCl) used to smother fire
ii. May not be in an extinguisher, but in a bucket!
d. Halon Extinguishers
i. Historically: CBrClF2 or CBrF3 (but damaged ozone)
ii. Dichlorotrifluorethane is a “greener” alternative using Argon as propellant
iii. Expensive, but don’t damage equipment
e. Carbon Dioxide = propellant and extinguishing agent; good for Class B/C Fires
6. Class D Fires: Active Metals
a. Good reducing agents (easily oxidized)
b. Na, K, Li—Alkali Metals (2 Na + 2H2O -----> H2 + 2NaOH)
c. NaH (sodium hydride), LiAlH4 (LAH), RMgX, RLi (Grignard or Alkyl Lithium)
d. Water is the worst thing to add to one of the fires: makes it worse!
e. Often are used in flammable organic solvents for reactions
f. A bucket of sand may be your best bet
g. The sand may put out the metal fire, but you might need a BC or ABC extinguisher
to put out the burning organic solvent that often accompanies this fire
7. What if you have a fire in a Chemical Hood
a. Recommended: Close the hood and evacuate if you don’t think you can put it out
b. Hoods draw air from the room and expel it out the top of the building—feeds fires
c. Hoods may automatically turn off if fire alarms are evacuated
d. If the fire alarm goes off and you are working in a fume hood, you may no longer be
safe to use hazardous chemicals any more
D. Section 2.1.3 Chemical Spills on You and the Lab
1.
Incident 2.1.3.1 Phenol Chemical Burn
2.
Chemical Spill Basics
a. Run a wide range of severity: 1 M NaCl(aq) vs. Conc. HNO3 vs. 4L Acetone
b. For introductory labs: don’t try to clean up spills, notify instructor for help
c. Toxic fumes or chemical burns on skin may require evacuation or calling 911
3.
Spills that Don’t Contaminate People
a. Solid spills
i. Usually aren’t that hazardous, since they don’t fume or spread easily
ii. Have someone guard the area and notify an instructor
iii. Brush into a dustpan to remove most solid and dispose of properly
Don’t put it back into the bottle because it is now contaminated
Don’t put it in a trash can, unless directed by instructor (NaCl(s))
iv. Wipe down area with wet towels to remove final traces—dispose of properly
b. Liquid Spills: always notify instructor immediately for help
i. Most aqueous solutions won’t be flammable or toxic
ii. Organic liquids may be toxic and/or flammable
- Don’t let a spill turn into a fire: remove ignition sources, turn off heat
- Cleanup may result in being overcome by vapors: always get help
iii. If properties aren’t known or are toxic/flammable: evacuate the room
iv. Contain the liquid so it doesn’t spread: use sand or another absorbent
- If you use up a spill kit, let someone know so it can be replaced
- Paper towels can be used, but they must be disposed of properly
4. Splashes in Your Eyes
a. You are required to wear goggles/safety glasses to avoid just this
b. Each lab should have an Eyewash Station
i. Need to know where it is; you may not be able to see well (can get help)
ii. Get the eyewash activated (it should stay on by itself)
iii. Stations should be checked out weekly
- Let water run for 3 minutes to flush out debris/bacteria
- Make sure water flows evenly from both sides
- Make sure no equipment is blocking the station
- Let someone in charge know if it is not working properly
iv. Flush your eyes for at least 15 minutes (will seem like forever)
- Get assistance
- Need to hold eyelids open or have someone help (natural to close them)
- Remove contacts
- Move your eyeball around so it is all flushed
v. Seek medical attention immediately
- Make sure all chemical out
- Determine if any damage done
- Determine if further treatment is needed
- Find out what the chemical was; MSDS Sheet helpful
5. Spills that Contaminate People
a. Introductory Labs would likely have Strong Acids and Strong Bases
b. Wear appropriate clothing to avoid skin contamination
i. Gloves
ii. Lab Coat
iii. Goggles
c. Remove the contaminant as soon as possible
i. Scrape solid off of your skin immediately
ii. Then wash with copious amounts of water in a sink
d. Report the incident to an instructor after you start washing (have someone else tell)
6. Using the Emergency Shower
a. Each lab (or just outside the door) should have an emergency shower
b. Use if you spill a large amount of a chemical on you and your clothing
c. Deluge Shower dispenses >75 L before it stops; Others have a off/on controls
d. The water is not heated! It will be cold! Cold is better than Dead!
e. Can also be used in case of fire
f. Remove the contaminated clothing ASAP, then rinse your skin more
g. Clear the room and encourage safety over modesty
h. Removed Clothing should be considered contaminated = hazardous waste
i. Seek medical assistance as soon as possible; take MSDS sheet with you
E. Section 2.2.2 Containment and Cleanup of Chemical Spills
1.
Incident 2.2.2.1 Mixed Solutions Spill
2.
Who should clean up a major spill?
a. Generally, student and even instructors should not be the cleanup team
b. OSHA requires HAZWOPER (Hazardous Waste Operations and Emergency
Response) training for most hazmat (hazardous material) spills
c. Sometimes, waiting may make the situation worse, so cleaning up is the best action
3. General Procedures
a. Evacuate—either the room or the whole building if needed (Pull Fire Alarm)
b. Communicate—alert instructor or supervisor that a spill has occurred (ask for help)
i. Appropriate authorities may need called
ii. Action should be taken to keep others out of the area of the spill
c. Isolate—limit the spreading out of the spill with sand, absorbent, paper towels
d. Mitigate—if the risk is low, you may participate in cleaning up the spill
4.
Containment and Cleanup
a. Never hesitate to ask for help (>100 ml probably should involve others)
b. Chemical Spill Kits
i. Supplies for cleaning up certain kinds of spills are sold commercially as kits
ii. Usually contain written instructions
iii. Don’t use if you haven’t been trained
c. Containing spills
i. Commercial “pillows”, “socks”, “pads” can absorb many times their mass
ii. Absorbing ≠ Neutralizing; chemical will still be toxic/hazardous
iii. Don’t use “pillows” for highly reactive compounds
iv. Use sand or kitty litter to build a “dike” around the spill if you need to
5. Acid and Base Spills
a. “Universal Chemical Absorbent” = 1:1:1 kitty litter/Na2CO3/sand
b. Vermiculite = expanded mineral (with heat) to make absorbent
c. Neutralizing agent can be used
i. Na2CO3, NaHCO3, or CaCO3 are often used to neutralize acids
ii. Commercial agents (Neutrasorb, Spill-X-A, or Hazorb) may contain indicator
iii. Don’t use on highly reactive spills (HF, Fuming H2SO4, RCOOOH)
iv. Vinegar (Acetic Acid), Hazorb, Spill-X-C, or Neutracrit can be used for bases
6. Solvent and Flammable Liquid Spills
a. Small spills can be cleaned up with paper towels left in the hood to evaporate
b. Larger spills
i. Vermiculite, kitty litter, activated charcoal can be used
ii. Spill-X-S, Solusorb, or Chemsorb are commercial absorbents
iii. Need to act quickly to prevent vapors from becoming concentrated
iv. May need to wear respirators to avoid fumes when cleaning up
v. Must be trained to use a respirator correctly
7. Mercury
a. Spill kits are available
b. Generally an absorbent bonds to the mercury to make it a solid
c. Indicators can color any remaining mercury so you can see it better
8. If you decide to clean up a spill…
a. Wear appropriate safety equipment: goggles, gloves, respirator, etc…
b. Contain it before cleaning it up
c. Add an absorbent
d. Transfer the contaminated absorbent to a bucket or designated container
e. Wipe up with paper towels; put them with the rest of the cleaned up absorbent
f. Close the container, label it with what is in it, call authorities to dispose of
9. Leaking Gas Cylinders
a. Find out what gas it is (N2 not a big deal, HCN a very big deal!)
i. N2, O2, He, Ar—not safety hazards
ii. CO, HCN, NH3, HCl—are hazardous
b. Large leak of hazardous gas should prompt evacuation
c. Used soapy water to pinpoint the leak (bubbles form over the leak)
d. Turn off main cylinder valve; tighten any connections; turn back on (if safe!)
e. If cylinder is leaking where it joins the main valve
i. You won’t be able to fix this
ii. Call for professional help (Environmental Health and Safety, EHS)
iii. Try to move cylinder outside, or into a hood if small
f. Flammable gas leak: don’t turn off any switches, sparks may ignite gas
Evacuate immediately and call for help; do not attempt to fix or clean up
F. Section 2.1.4 First Aid in the Lab
1.
2.
Incident 2.1.4.1 CPR Revives Researcher after Electrical Shock
Injuries Do Happen
a. Statistically impossible to avoid all injuries
b. You should be ready to help when the inevitable injuries do occur
c. Knowing what not to do may be as important as knowing what to do
d. “Good Samaritan” laws generally protect you from liability if rendering aid
3. Inhalation of Gases and Vapors
a. Lack of oxygen may lead to asphyxiation
b. Remove the person from the lab and get them to fresh air
c. Don’t become the next victim
i. Assess the safety of the situation before going into the lab
ii. Call for help before you go it
iii. Give CPR if needed and you have been trained
4. Skin and Eye Exposure to Chemicals
a. Rinse the eye or skin with copious amounts of water for at least 15 minutes
b. Some solids are water reactive, scrape off the skin prior to washing the skin
c. Get to a doctor for any eye or large skin exposures
5. Burns (thermal burns only discussed here)
a. Remove the source of heat
b. Remove clothing, jewelry, etc… from affected area
c. Cold tap water can cool burns (not if open blisters) and
d. limit further damage
e. Don’t apply creams or salves
f. Don’t apply ice, as you may cause frostbite
g. Transport to an emergency room ASAP
6. Electric Shock
a. Turn off the source of electricity and be sure it is off before rendering aid
b. You may be shocked by touching a victim still in contact with electricity
c. Administer CPR if needed and you are trained
d. Call 911 and/or get to medical attention ASAP
7. Exposure to Extreme Cold
a. Liquid Nitrogen (77K) and Dry Ice (-78 oC) are ubiquitous in many labs
b. Brief contact generally causes no damage
c. Remove the cooling agent and warm the effected area with warm (not hot) water
d. Frostbite may exhibit hard, white skin—transport to emergency room
e. Don’t rub the area to warm it up—causes more damage
8. Cuts or Open Wounds
a. Small cuts can be cleaned and bandaged
b. Large wounds: apply direct pressure and call 911
c. Don’t remove any impaling object
d. Treat for shock
i. Keep patient warm
ii. Elevate their feet
iii. Have them lie down (so as not to faint)
9. Traumatic Injuries (Explosion, Fall, Broken Bone)
a. Call 911 immediately
b. Assume spinal cord injury and don’t move the patient unless necessary
c. Stabilize the head and neck
d. Don’t try to reset a broken bone!
10. Exposure to Biological Agent
a. Don’t become the next victim; don’t render aid unless you will be safe from
exposure
b. Separate the patient from the pathogen
c. Transport to an emergency room for assessment
d. Have as much information about the exposure as possible for medical personnel
11. Radiation Exposure
a. Not much you can do as “first aid”
b. Separate the patient from the source of radiation and get to emergency room
12. General Issues
a. Don’t become a victim yourself
b. Have as much information for medical personnel as possible
c. Wear gloves—should be available in most labs
d. Let someone else know before rendering aid
e. Call 911 (they’d rather have a false alarm than a dead patient)
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