Scavenging & Pollution Control

Question 1

Advantages of active scavenging (4)

Answer 1

Most reliable
Efficient
Low running cost
Allows for N2O use

Question 2

Disadvantages of active scavenging (2)

Answer 2

Vacuum piping system expensive

Requires regular maintenance

Question 3

Advantages of passive scavenging (3)

Answer 3

Simple to operate
No suction required
Inexpensive to set up

Question 4

Disadvantages of passive scavenging (3)

Answer 4

Inefficient

• relies on resp. Effort
• affected by tubing resistance and wind conditions

Impractical in some buildings
Increased risk of leaks in comparison to active

Question 5

Advantages of charcoal canisters (2)

Answer 5

Not set up cost

Mobile

Question 6

Disadvantages of charcoal canisters (6)

Answer 6

Does not remove N2O
Increases circuit resistance
Not shut off when full
Must be weighed frequently
Continued cost of replacement
Heating canister causes release of volatile agents