CLS 272 UNIT 1/LAB PRACTICAL 1 STUDY GUIDE

what does RACE stand for?

• Rescue

• Alarm

• Confine

• Extinguish or Evacuate

what are the four components needed for a fire to occur? what are their roles?

1. fuel → combustible material

2. heat → raises the temperature of the material until it ignites

3. oxygen → maintains the combustion

4. chemical reaction → produces the fire

what is a class A fire? what is needed to extinguish it?

• fire that can occur due to ordinary combustible material like wood and paper

• to extinguish, use water/water-based solutions

  • soda and acid fire extinguisher

what is a class B fire? what is needed to extinguish it?

• fire can occur through flammable liquid and vapors like paint, oil, grease, and gasoline

• to extinguish, block oxygen or smother the fire

  • foam, dry chemical, or CO2 fire extinguisher

what is a class C fire? what is needed to extinguish it?

• fire that can occur through electrical equipment

• to extinguish, use nonconducting agents

  • dry chemical, CO2, halon fire extinguisher

what is a class ABC fire extinguisher?

a fire extinguisher that can be used for class A, B, and C fires by using dry chemical agents to smother the fire

what is a class D fire? what is needed to extinguish it?

• fire that can occur through combustible or reactive metals (Na, K, Mg, Li)

• to extinguish, use dry powder or sand

what is a class K fire? what is needed to extinguish it?

• fire that occurs through high-temp cooking oils , grease, or fats

• to extinguish, use agents that prevent splashing, cool, and smother the fire

  • K-based alkaline liquid extinguisher

what does PASS mean?

• Pull

• Aim

• Squeeze

• Sweep

identify what the symbols are starting from the top left

1. health hazard

2. flame

3. exclamation mark

4. gas cylinder

5. corrosion

6. exploding bomb

7. flame over circle

8. environment (non-mandatory)

9. skull and crossbones

identify the meaning of this safety label from 1-8, explain them too

1. hazard statement = nature of the hazard

2. hazard class = class of the hazard

3. safety precautions = the necessary precautions to be safe when handling the product

4. NFPA hazard code = a way of communicating the dangers of the material to emergency responders

5. fire extinguisher type = fire extinguisher needed to extinguish

6. safety instructions

7. formula weight

8. lot number = to track the product’s history

what does the red mean on an NFPA label?

flammable and should be stored in an area away from flammable reagents

what does blue mean on an NFPA label?

health hazard, toxic if inhaled, ingested or absorbed through the skin and must be stored in a secure area

what does yellow mean on an NFPA label?

reactive and oxidizing reagents which may react violently with air, water, or substances and must be stored away from flammable and combustible materials

what does white mean on an NFPA label?

corrosive, may harm the skin, eyes, or mucous membrane and must be stored away from red, blue, yellow-coded reagents

what does gray mean on an NFPA label?

moderate hazard and can be stored in a general chemical storage

why is the fourth segment left blank on an NFPA label?

for special warnings like if it is radioactive

explain what the numbers mean for each color-coded segment in an NFPA label?

• 4 = extreme

• 3 = severe

• 2 = moderate

• 1 = slight

• 0 = no hazard

what is a flocked swab?

collection material resembles bristles of a brush

what is a mattress swab?

collection material wrapped around a flexible shaft and absorbs the specimen through the middle

what is important when collecting a sputum sample?

knowing the difference between saliva, sputum, and nasal secretions and the sputum can be contaminated with oropharyngeal flora

how would you pack an infectious substance?

• needs triple packaging → primary leakproof receptacle with absorbent material incase the specimen leaks/breaks, leakproof secondary packaging, and a rigid outer packaging

• name, address, and phone number of the shipper

• infectious substance label

what do the different levels of specimen prioritization mean?

• level 1 = life threatening/criticial/invasive

• level 2 = possible degradation or contaminant overgrowth (refrigerate) and unpreserved

• level 3 = possible inaccurate quanititation (preservative)

• level 4 = holding or transport media preserve sample

what is nonselective media?

supports growth of most nonfastidious organisms (sheep blood)

what is selective media? give an example of two medias

• supports growth of one type of organism but not another (gram negative and gram positive)

• ex. macconkey = gram negative

• ex. phenylethyl alcohol (PEA) = gram positive

what is differential media? give examples of two medias

• allows grouping of microbes based on demonstrated characteristics on the media

• ex. sheep blood agar = non selective differentiates hemolysis

• ex. macconkey agar = differentiates lactose fermenters

what is enriched media? give an example

• contains growth factors added to nonselective media to allow fastidious organisms to grow

• ex. chocolate agar

what is enrichment broth?

liquid medium designed to encourage small numbers of organisms to grow and suppress other flora present

what is broth media?

supplement to agar to detect small number of aerobes, anaerobes, and microaerophiles

in what order would aerobes, anaerobes, and microaerophiles be seen in a thioglycolate broth?

• aerobes = top

• anaerobes = bottom

• microaerophiles = in the middle

how do you do a four quadrant isolation streak?

• place loop with specimen into broth, roll swab, or place drop of liquid specimen at the TOP of the plate

• from the TOP, spread the specimen in a tight zigzag horizontally for first quadrant

• for the second quadrant = sterilize the loop, rotate the plate, then go into the first quadrant to grab the microorganisms and go into another tight zigzag

  • applies for the third and fourth quadrant

what are the incubation conditions?

• most cultures will grow between 35 C and 37 C

• most will be incubated for 48 to 72 hrs

• some cultures will be held for 5 to 7 days

• place petri plates upside down to prevent condensation which may ruin your plate

what is capnophilic?

higher CO2

what is microaerophilic?

reduced O2 and increased CO2

how should plates be labeled?

• label with initials, date (mm/dd/yy), time (military), organism name or code #

• NEVER label plate in the middle, should be around the side of the plate

• may use computer generated labels

what is the goal of streak plate isolation?

reduce the number of bacteria in each subsequent quadrant

what are colonies?

masses of offspring from an individual cell

what is aseptic technique the process of?

ultimately prevents contamination of a culture from the environment and yourself

what is sterilization?

destruction of ALL forms of life, including spores

what is disinfection?

elimination of a defined scope of microorganisms

what are the 10 factors that influence the degree of killing>

1. types of organisms

2. number of organisms

3. concentration of disinfecting agent

4. presence of organic material

5. nature (composition) of surface to be disinfected

6. contact time

7. temperature

8. pH

9. biofilms

10. compatibility of disinfections and sterilants

name the 7 microorganisms that are the most resistant to killing to least resistant

1. prions

2. bacterial spores

3. mycobacteria

4. nonlipid viruses

5. fungi

6. bacteria

7. lipid viruses

how do you sterilize with heat?

• using an autoclave which uses steam pressure for moist heat or heat

  • 1 atm at 121 C for 15 min destroys endospores

  • dry heat sterilizes glassware but requires longer contact time

how are cultures initially observed?

• colony morphology is initially observed 18 to 24 hrs post culture then is incubated for another 24 hrs after plate reading

• plate reading determines the growth of the M/O and the colony morphology

when using a macconkey plate, what would lactose fermenters and nonlactose fermenters look like? give examples

• lactose fermenters = pink

  • ex. E. coli/Citrobacter

• nonlactose fermenters = colorness

how do you see hemolysis on a blood agar?

observe the media immediately surrounding or underneath the colony by using transillumination

what is important regarding hemolysis on a blood agar?

important to determine whether true hemolysis is present or it is discoloration due to organism growth

what is alpha (α) hemolysis?

partial clearing of blood that results in a green discoloration of the medium; can see through the plate “a” little

what is beta (β) hemolysis?

complete clearing of blood cells (lysed) around the colonies; can look through the plate “mo beta”

what is gamma (γ) hemolysis?

nonhemolytic; can’t see through the plate at all

regarding size of colonies, what is larger? gram positive or gram negative?

gram negative (gram positive is less than gram-negative)

what are the four forms of colonies? explain them

1. smooth

2. filamentous = looks like thread or has connected cells that are forming a thread

3. rough or rhizoid = still looks somewhat like a circle with rough edges

4. irregular = doesn’t look like a circle at all

what is swarming?

hazy blanket of growth on surface

how would you determine elevation of a colony?

tilt the culture plate and look at the side

what are the five types of elevation? describe them

1. raised = raised flat top

2. convex = dome-shaped

3. flat = not raised

4. umbilicate = convex with a depressed center/pitting

5. umbonate = convex with a protuding nipple

what are the three types of density?

1. transparent

2. translucent

3. opaque

what are the four colors to describe colonies?

1. white

2. gray

3. yellow

4. buff (pale yellow-brown)

what are the five consistencies that describe colonies?

1. brittle (splinters)

2. creamy

3. dry

4. waxy

5. sticky = entire colony comes off the plate

what are pigments?

inherent characteristics of a specific organisms confined generally to a colony

how would you determine the odor of a colony?

when the lid comes off (NEVER inhale directly from the plate)

what is the “streamer” description for organisms in liquid media?

vinelike growth in media, puff ball-like, scumlike growth