Retake

Question 1

When lifting from open water, what would a compuond reading of -0.2 indicate?

Answer 1

A lift of 2 metres

Question 2

What are the sizes of soft suction hose available

Answer 2

45mm
70mm
90mm
150mm

Question 3

What would cause a decrease in low pressure when working on the pump

Answer 3

• branches being opened
• burst delivery hose
• the appliance tank is empty

Question 4

When would you use a 90mm adaptor

Answer 4

When connecting a storz coupling to an instantaneous coupling

Question 5

What are the safety precautions when using a ladder

Answer 5

• Risk assess potential access points before pitching the ladder.
• Make sure the ladder is long enough for the task.
• Make sure the ladder is placed on stable ground and pitched at a safe angle.
• Be aware of overhead obstructions and electricity cables.
• Make sure the head of the ladder is resting on a stable point and tie the head off when additional security is required.
• Take care to avoid knocking the ladder when moving equipment or hose.

Question 6

What is the length of the hard suction hose

Answer 6

2.44 m

Question 7

What is the single most important factor affecting pressure loss

Answer 7

Diameter of hose

Question 8

When lifting from open water, what would cause an increase in pressure on the compound gauge

Answer 8

• Level of supply dropped (tidal or water source used up).
• Suction strainer blocked.
• Branches opened.
• Burst delivery hose.

Question 9

How many lengths of hosereel hose are carried on the appliance

Answer 9

8

Question 10

What are the factors that affect pressure loss

Answer 10

Internal diameter of hose
(The smaller the internal diameter of the hose the greater the amount of frictional loss.)

Output flow of water
(The higher the required output, the higher the amount of frictional loss.)

Height in metres above or below the water source (Working above the water source will result in a pressure loss. Working below the water source will result in a pressure gain.)

Length of hoseline

Question 11

What are the two types of pump

Answer 11

Centrifugal (pumps fluid) and positive displacement (pumps air)

Question 12

What are the safety precautions when working on a ladder

Answer 12

• Three points of contact should always be maintained
• Do not overreach, make sure the centre of the body always stays within the strings of the ladder.
• Do not work on the top three rounds.
• Do not overload the ladder. Unless assisting a casualty down the ladder, a maximum of one person per extension is allowed.

Question 13

What would cause a decrease in the vacuum reading on the compound gauge

Answer 13

• Level of supply raised (tidal).
• Branches shut down.
• Slight air leak on suction side of pump.

Question 14

What are the reasons why we cannot create a perfect vacuum

Answer 14

Overcoming inertia
Frictional pressure
Pump entry loss
Imperfect vacuum
Temperature
Atmospheric pressure

Question 15

Define a primer

Answer 15

A device which can pump air