Levelling Equipment

Question 1

What are the two broad categories of levels?

Answer 1

Optical aka builder’s level -> two people are needed to operate them. Looks through scope + interprets the reading.

Electronic levels -> rotate a light beam / only require one operator

Question 2

Which way can a builder’s level move? (horizontal or vertical)

Answer 2

Horizontal

Question 3

What are some fun facts about the “Dumpy” levels (aka 4-pin levels)

Answer 3

• Least expensive
• Least sensitive
• The hardest to correctly set up

Question 4

What are 2 types of manual levels? (DT)

Answer 4

Dumpy

Tilting

Question 5

What is split bubble or engineer’s level also called?

Answer 5

Tilting level.

Question 6

What type of levels only have a fish - eye bubble + prism inside.

Answer 6

Automatic levels

Question 7

What are 2 features of an Optical instruments

Answer 7

1) Crosshairs + stadia lines inside the viewfinder

2) An eyepiece focus (for the crosshairs)
- Reading are taken from crosshairs

Question 8

What does a beam detector or sensor use to locate distances?

Answer 8

Infrared laser beam

Question 9

What are Stradia lines used for?

Answer 9

To measure distance

Question 10

Where are the leveling split bubble on the dumpy level?

Answer 10

Above or below the barrel

Question 11

Where is the levelling split bubble located on a tilting level?

Answer 11

Alongside the barrel

Question 12

What type of bolt connects the head plate to the tripod?

Answer 12

5/8ths NC bolt

Question 13

What is Bri’s birthday?

Answer 13

June 17, 1988

Question 14

When is Lenny’s birthday?

Answer 14

June 27, 2020

Question 15

When is Frankie’s birthday?

Answer 15

November 18, 2020

Question 16

What type of bolt is a NC bolt?

Answer 16

Course

Question 17

A metric scale are shown in divisions of what?

Answer 17

In 10 mm (1 cm) divisions

Question 18

Architect’s rod readings are in divisions of what?

Answer 18

1/8 in increments

Will also have 11 inch markings on it.

Question 19

What are Engineer’s rods measured in?

Answer 19

0.01m increments

Question 20

How do you set up the tripod?

Answer 20

Have all 3 legs closed / in contact with the ground

Bring the tripod top plate at chin level

Question 21

How do you set up the tripod if the ground is sloping?

Answer 21

Put two legs on the downhill side and the other one uphill

Question 22

If the elevation measured is higher than the instrument, how do you hold the rod?

Answer 22

Upside down

Question 23

If the elevation is lower than the instrument, how do you hold the rod?

Answer 23

upright and plumb

Question 24

True or false: equal length back sights + foresights will cancel errors caused by crosshairs not being in perfect adjustment?

Answer 24

True

Question 25

What is the point of a peg test?

Answer 25

It is the only way to check the position of the crosshairs at the job site.

Question 26

How do you get the mounting head or top plate of a builder’s level, level?

Answer 26

Adjusting the legs

Question 27

If the tripod legs are not able to dig into anything, what must be done?

Answer 27

Use rubber tips or suction cups or place the tripod in a triangular frame to prevent slipping.

Question 28

What happens to the air bubbles in level vials in extreme heat?

Answer 28

Heat can expand the air bubbles and make it very difficult to read.
to avoid heat: put some sort of sunshade over the instruments.

Question 29

How are you suppose to carry the tripod outside in wide open spaces?

Answer 29

Over the shoulder tripod legs in front

Question 30

If there are obstacles or doorways, how do you carry the tripod?

Answer 30

Tripod legs behind, over the shoulder with the instrument in front.

Question 31

What is the most common benchmark measurement?

Answer 31

100ft

Question 32

What establishes the height of the instrument?

Answer 32

The back-sight

Question 33

What type of readings are taken on points of unknown elevation / used to determine the elevation of a turning point or final point in a survey?

Answer 33

The Fore-sight

Question 34

How do you figure out the height of the instrument?

Answer 34

Elevation/ benchmark + Back-sight = Height of elevation

Question 35

What is done with an inversion reading?

Answer 35

• If it’s a back-sight reading => it is subtracted from the elevation to get the height of instrument.
• If it’s a foresight reading => it is added to the height of instrument to get the new elevation.

Question 36

Why do we get an inversion reading?

Answer 36

Because the line of sight of the instrument is above the BM

Question 37

A normal reading on a builders level means what?

Answer 37

That the line of sight of the instrument is below the benchmark.

Question 38

What is a Turning Point?

Answer 38

Is set when moving the instrument to a new location.

Question 39

What type of beam does an electronic level use?

Answer 39

An infrared laser beam

Question 40

With the legs closed + extended, to what height should the tripod’s top plate be adjusted before setting the tripod / mounting the instrument?

Answer 40

The bottom of your chin

Question 41

When setting up a tripod on sloping ground, how should the legs be positioned?

Answer 41

With one leg uphill

Question 42

What is Zero Datum?

Answer 42

Mean sea level (the average between high/low tide)

Question 43

Explain the term - Elevation

Answer 43

The height of any point above zero datum.

Question 44

Explain the term - Benchmark

Answer 44

A known elevation

Points measuring changes of elevation across the land.

Question 45

What is Backsight?

Answer 45

Rod readings take on a point whose elevation is known.

Question 46

Explain Foresight

Answer 46

Rod readings taken on a point whose elevation is yet to be established.