Washer Disinfectors

Question 1

What are the load recommendations for instruments in the washer disinfector?

Answer 1

• no overlapping or shadowing
• hinged instruments open at the hinge

Question 1

What are the daily tests required to be carried out on a washer disinfector?

Answer 1

• check load carrier
  
  • damage
  • remaining instruments
• check spray arms
  
  • no obstructions
  • spinning freely
  • spray jets unblocked
• check strainer folder condition
  
  • previous instruments
• check condition of door seal
• check chemical level

Question 2

What are the 5 core stages of the washer disinfector?

Answer 2

• flush/pre-wash
• main wash
• rinse
• thermal disinfection
• drying

Question 3

What is the function of the flush/pre-wash stage of the washer disinfector?

Answer 3

remove gross contamination

Question 4

What is the function of the main wash stage of the washer disinfector?

Answer 4

uses detergent to more effectively remove biological matter

Question 5

What is the function of the rinse stage of the washer disinfector?

Answer 5

removes remaining residue, both chemical and biological

Question 6

What is the function of the thermal disinfection stage of the washer disinfector?

Answer 6

kill microorganisms with high temperatures

Question 7

What is the function of the drying stage of the washer disinfector?

Answer 7

hot air used to remove remaining moisture

Question 8

What can be removed during the washer disinfector stage but by no other equipment?

Answer 8

prion proteins

Question 9

How does the water used in a washer disinfector differ from other pieces of equipment?

Answer 9

there is fresh water used for every individual stage

Question 10

What temperature is required for the flush/pre-wash stage and why?

Answer 10

<35 degrees

• proteinaceous content still present
  
  • heat will congeal onto instrument

Question 11

What temperature is required for the main wash stage?

Answer 11

• higher than flush/prewash
  
  • dependent on the chemical used
  • set up during validation
    
    • new validation for new chemical

Question 12

What temperature is required for the rinse stage?

Answer 12

<65 degrees

Question 13

What temperature is required for the thermal disinfection stage?

Answer 13

• 90-95 degrees
  
  • minimum 1 minute

Question 14

What temperature is required for the drying stage?

Answer 14

• generally over 100 degrees hot air
  
  • to remove all moisture
    
    • cannot sterilise if wet
    • can damage packaging

Question 15

What is the average cycle time for a washer disinfector?

Answer 15

• > 60 minutes
  • drying cycle tends to be the longest section