INFECTION CONTROL - decontamination

Question 1

what is decontamination?

Answer 1

the process of cleaning, rinsing, disinfection, drying, inspection, and sterilisation

Question 2

what guidance documents are used for detcontamination?

Answer 2

Health Protection Scotland (HPS)
www.scottishdental.org
Scottish Health Technical Memoranda (SHTM)
Scottish Health Technical Note (SHTN)

Question 3

what does disinfecting alone not get rid of?

Answer 3

bacterial spored
you must sterilise too

Question 4

what defines an instrument as sterile?

Answer 4

when the probability of a viable microorganism being present in or on a device following a validated sterilisation process is less than one in a million

Question 5

what are the top 3 most resistant microorganisms?

Answer 5

prions
bacterial spores
mycobacteria

Question 6

what are the least 3 resistant types of microorganisms?

Answer 6

large non-enveloped viruses
gram-positive bacteria
lipid enveloped viruses

Question 7

what is the criteria for local decontamination unit users?

Answer 7

fully vaccinated against Hep B
trained in the standards of infection prevention and control
can perform periodic testing of equipment and maintain accurate records

Question 8

what is COSHH?

Answer 8

control of substances hazardous to health

Question 9

what are substances hazardous to health?

Answer 9

biological agents - bacteria, viruses, fungi
chemicals
fumes
dust
vapours

Question 10

what temperature should water be for manual cleaning?

Answer 10

30-35 degrees Celsius (should not exceed 45 as prions can start to coagulate and fix to instrument surfaces making cleaning more difficult)

Question 11

what are features of an ultrasonic cleaner?

Answer 11

• interlocking lid to prevent operation with lid open and aerosols
• suspended baskets for instruments
• drain-tap to enable chamber being emptied
• control of process variables such as temperature and time (6-10 min cycle)
• a datalogger to give a retainable record of each cyc;e

Question 12

what must you do prior to using the ultrasonic cleaner?

Answer 12

run first cycle empty to de-gas the solution

Question 13

what dental instruments can not be cleaned in the ultrasonic?

Answer 13

dental handpieces

Question 14

what temperature does the ultrasonic cleaner normally work at?

Answer 14

25-35 degrees Celsius

Question 15

how often should solution in the ultrasonic cleaner be changed?

Answer 15

every 4 hours or if visible contaminated

Question 16

what are the daily tests for the ultrasonic cleaner?

Answer 16

automatic control test
inspection of instruments

Question 17

what are the weekly tests for the ultrasonic cleaner?

Answer 17

foil ablation testing
cleaning efficacy testing

Question 18

what should be used to dry equipment after the cleaning process?

Answer 18

lint-free towels

Question 19

why should you not not leave cleaned instruments to air dry?

Answer 19

it will promote microbial growth and or corrosion of the instruments

Question 20

what are the main benefits of the washer-disinfector?

Answer 20

automated process
reduces risk of sharps injuries
minimal human contact with instruments
cleaning cycle is reproducible
disinfects as well as cleans
has a drying cycle

Question 21

what is the preferred method for the cleaning of dental instruments?

Answer 21

washer-disinfector

Question 22

what are the 5 stages of the washer-disinfector?

Answer 22

pre-wash
wash
rinse
thermal disinfection
drying

Question 23

what is required to do daily for the washer disinfector?

Answer 23

check the spray nozzles for blockages
ensure spray arms are freely rotating
check door seals
remove and clean strainers and filters

Question 24

what are the types of tests done on the washer-disinfector?

Answer 24

efficacy testing (daily/ weekly)
automatic control-test (daily/ weekly)
chemical test (quarterly/ annually)

Question 25

why are instruments packaged after sterilisation?

Answer 25

- prevent recontamination and sterilisation

Question 26

pre-sterilisation packaging material requirements?

Answer 26

- be made of non-shredding material - only a single layer of wrapping material used - allow placement of adhesive labelling

Question 27

what should a package label contain?

Answer 27

contents - sterile or not name of department/ clinic instrument identifier sterilisation cycle number steriliser number method of sterilisation - steam

Question 28

what are the 3 methods of sterilisation?

Answer 28

heat chemicals radiation

Question 29

what is sterilisation?

Answer 29

destruction/ removal of all living organisms and spores

Question 30

why is effective cleaning essential prior to steam sterilisation?

Answer 30

prion proteins are not fully deactivated by sterilisation any deposits left on instruments like blood, bone or cement will prevent penetration of steam

Question 31

what could prevent sterilisation steam not penetrating all surfaces?

Answer 31

instruments not being fully dried prior to sterilisation

Question 32

with steam sterilisation, what temperature and pressure hold is required to kill microorganisms?

Answer 32

134-137 degree celcius for a min of 3 mins at 2.1-2.25 gauge pressure

Question 33

what are the 3 types of sterilisation cycles?

Answer 33

type B - vacuumed type N - non-vacuum type S - not all compatible with sterilisation of wrapped/ hollow items

Question 34

what is the preferred method of steam sterilisation?

Answer 34

type B (vacuumed)

Question 35

what properties should the water in the steriliser have?

Answer 35

low mineral, pathogen and endotoxin free

Question 36

how often is the steriliser checked?

Answer 36

beginning of each day

Question 37

what are the 2 types of traceability?

Answer 37

through the decontamination process directly to the patient

Question 38

is dentistry classed as low or high risk regarding the transmission of vCJD?

Answer 38

low risk (but high risk for bloodborne viruses)

Question 39

how are dental instruments traced?

Answer 39

through the decontamination process

Question 40

what is FIFO?

Answer 40

first in first out system to allow for stock rotation