Safety

Question 1

The majority of centrifuge-related failures are due to what type of problem?

Answer 1

User error

Question 2

What are the most common user errors when using a centrifuge?

Answer 2

Failure to secure the rotor to the drive, to put the lid on top of the rotor, and to secure the lid

Question 3

Why is it important to use the correct rotors and containers in a centrifuge?

Answer 3

Effectiveness and safety

Question 4

What should you do before you insert the rotor?

Answer 4

Drive spindle is clean and bowl should be dry

Question 5

What can eventually cause any rotor to fail?

Answer 5

Corrosion and fatigue of the material

Question 6

Why is balancing samples in the rotor so important?

Answer 6

Imbalance could cause breakage of samples and damage to centrifuge

Question 7

What problems should you look for during regular visual inspects of a rotor?

Answer 7

Rough spots, pitting, discoloration, white power deposits

Question 8

Why should centrifuge containers/tubes not be overfilled?

Answer 8

Centrifugal force will bring the samples to overflow

Question 9

Why is it important to keep careful logs of rotor usage?

Answer 9

• To determine the age of the rotor
• Gives idea of lifetime of rotor
• Determines when it is time to replace it

Question 10

What is a good source of information concerning a chemicals safety hazards?

Answer 10

Material safety data sheet (MSDS)

Question 11

What three items should always be worn when working with hazardous chemicals?

Answer 11

Lab coat, gloves, safety glasses

Question 12

Why might putting a warm jar or bottle on a cold surface be hazardous?

Answer 12

Glass could crack and could allow fluid to escape

Question 13

Why is a secondary container useful?

Answer 13

In case the primary container cracks, no spills will occur

Question 14

Why is it useful to perform a “dry run” of a protocol using hazardous chemicals?

Answer 14

To identify possible hazards

Question 15

How can you reduce risks inherent with using large stock containers?

Answer 15

By preparing several small stock tubes

Question 16

Can all solid and liquid chemicals be stored together?

Answer 16

No

Question 17

What are properties of essentially all organic liquids?

Answer 17

Combustible

Flammable

Question 18

What are compatibility tables used for?

Answer 18

To see if one chemical is compatible to store safely with what other chemicals

Question 19

Why is it a good idea to store liquids on lower shelves and cabinets?

Answer 19

In case of a spill, they are below eye level and will not drip on other shelves

Question 20

What is the most important reason for proper chemical storage?

Answer 20

• to lessen the risk of fire
• to prevent accidental mixing in emergencies
• to minimize exposure to corrosive and toxic chemicals
• to provide for effective management of chemicals

Question 21

Why should oxidizers be stored separately?

Answer 21

They are highly reactive

Question 22

What are properties of most oxidizing acids that require consideration in their storage?

Answer 22

Corrosive

Highly reactive

Question 23

On what type(s) of fire is an ABC or dry chemical fire extinguisher properly used?

Answer 23

On all three classes

A - paper wood
B - chemicals
C - electrical fire

Question 24

How do you handle a biological spill?

Answer 24

1 to 10 dilution of bleach for 20 mins

Spray with detergent disinfectant and wipe with alcohol

Question 25

How do you take care of a spill of an airborne pathogen?

Answer 25

- hold breath and exit room - remove protective clothing in other room - call for professional to clean it - put sign on door to warn others

Question 26

How do you handle a radiation spill?

Answer 26

- personal safety - radioactive waste goes in proper container - solution containing high phosphate concentration aides clean up - identify spill area - process repeated until there is no detection of radiation

Question 27

What immediate action should lab personnel take after a major spill?

Answer 27

- attend to injured person and remove them - call emergency number - alert others - assist personnel to clean up spill - avoid tracking spill

Question 28

If there is a major fire in the lab, what actions should be taken by any and all lab personnel?

Answer 28

``` Inform coworkers Pull fire alarm Take stairs Evacuate to safe area Attend to injured person Close doors ```

Question 29

How do you clean up a chemical spill?

Answer 29

- washing with detergents - chemical spill clean up kit should be used. Contains absorbance pads, reactants, and instructions - label the disposal bag - seal disposal bag - call for experienced personnel

Question 30

How do you deal with solvent fires (on a person) in the lab?

Answer 30

Smothering (stop, drop, and roll) | Don't touch with hands

Question 31

What is meant by "being your brothers keeper" in a safe lab setting?

Answer 31

Pay attention to others. Advise them of possible errors

Question 32

What is done when you or someone else is injured?

Answer 32

Tell personnel Immediate rinsing Removal of clothing Careful finding and vigorous with soap

Question 33

What is the risk of HBV infection for lab workers relative to the general population?

Answer 33

2 to 7 times as high

Question 34

What are the hazards of using acrylamide (used in making electrophoretic gels)?

Answer 34

All are hazards - neurological effects - carcinogenic potential - potential reproductive and developmental effects - rapidly absorbed through skin - easily spread with air current

Question 35

What is the most effective practice in using protective gloves?

Answer 35

Changing gloves when contaminated

Question 36

Phenol poisoning can occur through which routes of exposure?

Answer 36

Inhalation | Through skin absorption

Question 37

When working with hazardous powders, what are the main risks? How can the risks be minimized?

Answer 37

Measuring and mixing are high risk procedures Working under the hood can reduce the risk

Question 38

Why are fume hoods potentially hazardous?

Answer 38

An air disturbance can cause the vapor to escape

Question 39

What are some good lab practices to reduce safety hazards, especially if using human blood?

Answer 39

- washing hands thoroughly - dispose all contaminated material appropriately - decontaminating before washing - disposing of sharps

Question 40

How can simply heating a closed bottle or jar in a microwave be hazardous?

Answer 40

The jar could explode, blowing the microwave door off

Question 41

When are wearing safety glasses, goggles and face shields appropriate?

Answer 41

Safety glasses when you work with small quantities Goggles when you work with quantities of more than 1 liter Face shield is for working with very large quantities

Question 42

What should be the first action in response to a phenol spill or splash on the skin?

Answer 42

Flush with water

Question 43

Which lab accidents involving blood-borne pathogens can cause infections?

Answer 43

Needle puncture | Splash in the eye

Question 44

Why should wearing a lab coat be a standard safety precaution?

Answer 44

Because it prevents spills from reaching the skin

Question 45

At 100 V, what current level is sufficient to deliver a lethal shock?

Answer 45

25 mA

Question 46

How might failure to report a spill or contamination be detrimental to others?

Answer 46

Bad for work environment Bad for trust between workers Puts everyone at risk

Question 47

Which of these common procedures of using ethidium bromide offer a significant exposure hazard?

Answer 47

Preparation of stock solution and the use in CsCl gradients