3 - Manual washing and cleaning

Question 1

Why is it essential to manually clean instruments before sterilisation?

Answer 1

This is stage at which prions and and proteins are removed

Question 2

What PPE is required for manual cleaning?

Answer 2

• apron
• face shield
• rubber gloves
• heavy duty rubber gloves

Question 3

Describe the sink used for manual cleaning.

Answer 3

• dedicated sink only for manual cleaning
• cannot be used for hand washing or any other purpose
• a separate sink is required for rinsing instruments

Question 4

Describe the water used for manual cleaning.

Answer 4

• tap water is suitable
• temperature must be 30-35 degrees

Question 5

Why must the water temperature not exceed 35 degrees?

Answer 5

• proteins will start to coagulate above the temperature
• makes proteins more difficult to remove

Question 6

Describe the cleaning agent used in manual cleaning.

Answer 6

Chemical detergents can be either enzymatic or pH neutral detergent

Question 7

What are the different methods of manual cleaning?

Answer 7

• immersion
• non-immersion

Question 8

Describe immersion manual cleaning.

Answer 8

• instruments immersed in water
• long handle soft bristle brush used to scrub instruments
• metallic brush should never be used as this could damage the instrument and cause corrosion

Question 9

Describe non-immersion manual cleaning.

Answer 9

• instruments washed above water level
• non-linting cloth used
• helps to prevent splash

Question 10

What is the typical concentration of detergent recommended by the manufacturers instructions?

Answer 10

5ml per 1l of water

Question 11

When should manual cleaning be carried out?

Answer 11

• when manufacturers instructions indicate the instrument is not suitable to a washer-disinfecter
• when there is no other alternative
• the automated process has failed to remove gross contamination

Question 12

How does an ultrasonic bath clean instruments?

Answer 12

• sound waves at high frequencies produced bubbles which implode on the hard surface of the instruments
• these bubbles have a scouring effect
• can damage instruments so MI should be consulted prior to use

Question 13

What is cavitation?

Answer 13

• bubbles form under fluctuating pressure
• the bubbles rapidly expand and collapse

Question 14

What is the typical temperature ultrasonic baths are set at?

Answer 14

20-30 degrees

Question 15

What must occur before the ultrasonic bath can be used to clean instruments?

Answer 15

• degas cycle
• this cycle removes the air bubbles in water
• this improves the efficacy of the bath

Question 16

What information should be recorded in the equipment log book when using an ultrasonic bath?

Answer 16

• date and time
• cycle number
• detergent added
• temperature
• length of cycle
• operator name

Question 17

How are instruments rinsed after manual cleaning and the ultrasonic bath?

Answer 17

• in a separate rinsing sink
• must be fully submerged in rinsing water

Question 18

What are the benefits of manual cleaning over a washer-disinfector?

Answer 18

• manually scrubbing exerts more force
• some instruments cannot be cleaned in the washer-disinfector due to MI
• ultrasonic baths are ferocious and good at removing contamination

Question 19

What are the drawbacks of manual washing compared to a washer-disinfector?

Answer 19

• staff member required to be present for the entire process
• risk of aerosol
• may contaminate surrounding environment
• human error
• sharps injures
• ultrasonic may damage instruments