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ContentsContents..................................................................................................................................................2

Unit of Competency................................................................................................................................4

Unit Descriptor........................................................................................................................................6

Topics.....................................................................................................................................................6

Recognition of Prior Learning.................................................................................................................6

Learning activities...................................................................................................................................8

Introduction...........................................................................................................................................10

Compliance documentation...............................................................................................................11

Safety and hazards...........................................................................................................................12

Environmental protection requirements............................................................................................14

Types of levelling work......................................................................................................................14

Terminology.......................................................................................................................................15

Levelling equipment..........................................................................................................................15

Selecting correct tool for the job........................................................................................................16

Checking equipment for serviceability...............................................................................................18

LEARNING ACTIVITY 1.......................................................................................................................20

Establish offsets for civil works.........................................................................................................23

Survey controls..................................................................................................................................23

Establish offset and recover pegs.....................................................................................................23

Re-establish earthwork and pavement control lines.........................................................................24

Establish drainage offsets from survey control.................................................................................24


Setting up and using levels...................................................................................................................26

Reading levels from plans or instructions.........................................................................................26

Set up and use levelling instruments................................................................................................26

Transfer heights from the known to the required..............................................................................27

Document results of levelling procedure...........................................................................................28


Environmental protection requirements............................................................................................33

Keeping equipment clean..................................................................................................................33

Maintenance of equipment................................................................................................................33

SkillsDMC © Learner Guide RIICCM208D Page 2 of 50-2

Disposing of waste............................................................................................................................34

Storing equipment.............................................................................................................................34


Check Your Understanding...................................................................................................................36

Knowledge questions............................................................................................................................37

Practical Activities.................................................................................................................................40

Answers to learning activities...............................................................................................................42

Learning activity 1.............................................................................................................................42





Unit of CompetencyRIICCM208D Carry out basic levelling

Application This unit describes a participant’s skills and knowledge required to carry out basic levelling in Civil construction.

This unit is appropriate for those working in operational roles.

Licensing, legislative, regulatory and certification requirements that apply to this unit can vary between states, territories, and Industry sectors. Relevant information must be sourced prior to application of the unit.

Element Performance CriteriaElements describe the essential outcomes of a unit of competency

Performance Criteria describe the required performance needed to demonstrate achievement of the element.

1. Plan and prepare for basic levelling

1.1 Access, interpret and apply basic levelling documentation, and ensure the work activity is complaint

1.2 Obtain, read, interpret, clarify and confirm work requirements1.3 Identify and address potential risks, hazards and environmental

issues, and implement control measures1.4 Select and wear personal protective equipment appropriate for

work activities1.5 Identify, obtain and implement traffic signage requirements1.6 Select equipment and/or attachments for work activities, and check

for faults and serviceability within specified tolerances1.7 Identify environmental protection requirements1.8 Obtain and interpret emergency procedures, and be prepared for

fire/accident/emergency

2. Establish offsets to plans and drawings

2.1 Establish offset and recovery pegs from survey controls to specified plans and drawings

2.2 Re-establish earthwork and pavement control lines from offsets and/or recovery pegs

2.3 Establish drainage offsets from survey control

3. Set up and use levelling device

3.1 Identify heights to be transferred/established from project plans or instructions

3.2 Set up and use levelling instruments, and complete levelling3.3 Transfer heights from the known to the required


3.4 Document results of levelling procedure

4. Conduct housekeeping activities

4.1 Clear work area and dispose of or recycle materials4.2 Clean and maintain condition of equipment, ensure suitability for

use, and address/report issues4.3 Manage/report hazards, and maintain a safe working environment4.4 Process written records


Unit DescriptorThis unit covers carrying out basic levelling in the Civil Construction Industry. It includes: planning and preparing for basic levelling, establishing offsets to plans and drawings, setting up and using levelling devices and conducting housekeeping activities

TopicsThe main topics covered in this Learning Guide are:

Understanding levelling Compliance documentation Signage Plant, tools, equipment Environmental protection requirements Types of levelling work Terminology Selecting correct tool for the job Checking equipment for serviceability Establish offsets for civil works Setting up and using levels Clean up Maintenance of equipment Disposing of waste Storing equipment

Recognition of Prior LearningIf you think you can satisfactorily complete the assessment for this section, check your knowledge and skills as follows:

I can: Access, interpret and apply compliance documentation relevant to the work activity Obtain and confirm safety requirements from the site safety plan and organisational policies

and procedures, and apply to the allotted task Identify, obtain and implement signage requirements from the project traffic management plan Select plant, tools and equipment to carry out levelling tasks consistent with the requirements

of the job, check for serviceability and rectify or report any faults Check levelling equipment for serviceability within specified tolerances, and report any faults Identify environmental protection requirements from the project environmental management

plan, and confirm and apply to the allotted task


Establish offset and recovery pegs from survey controls to specified plans and drawings to meet project requirements

Re-establish earthwork and pavement control lines from offsets and/or recovery pegs in accordance with plans, drawings and specifications

Establish drainage offsets from survey control Identify heights to be transferred/established from project plans or instructions Set up and use levelling instruments correctly in accordance with standard operating

procedures and manufacturer's guidelines Transfer heights from the known to the required Document results of levelling procedure and close them out to organisational requirements Clear work area and dispose of or recycle materials in accordance with project environmental

management plan Clean, check, maintain and store tools and equipment


Learning activitiesAs you work through this Learning Guide you will complete the following activities:

What compliance documentation do you need to be aware of and apply when doing levelling work and where is it stored?

What levelling equipment do you use in your workplace and what are they used for. Take a photo or draw a rough sketch of each of the tools and write 2 or 3 sentences about what they are used for.

Explain what ‘level’ work means and give three examples of types of work that could be done.

Explain in your own words the meaning of datum and bench mark.

How do you check a level for accuracy? Explain to your trainer, using a worksite

plan, where the survey controls are. Explain or demonstrate to your trainer

how you would establish offset and recover pegs from survey controls, re-establish earthwork or pavement control lines from offsets or recovery pegs, and establish drainage offsets from survey control

What is the difference between open and close traverse levelling?

Demonstrate or explain the rise and fall method of reduction.

How do you make sure that you have accurate recording of results of each levelling procedure?

Why should you clean tools after use? What should you do with waste (rubbish)

at the end of the project?

What workplace experience do I need?If you are employed in the industry, complete the unit activities using your workplace as an example.

If you are not employed in the industry, your trainer can assist you to demonstrate the application of this unit of competency in a number of ways:

you will undertake a work placement so you can experience a real work situation

you can work through case studies or other examples, provided by your trainer

you can visit as many worksites as possible to further assist with your assessment

How will I be assessed for this unit?Assessment for this unit will comprise of both practical and theory components. Details of the methods, location and times of these assessments will be provided to you by your assessor.

Throughout this Learner Guide you will see the term trainer. This is the person who will be guiding you through this unit of competency. It could be a workplace supervisor, mentor, trainer, instructor or tutor.

When the term assessor is used it refers to the person who will make the final judgement of your competency in this unit. Sometimes the trainer and assessor will be the same person. In some cases they will differ.


The assessor will collect a range of evidence which shows how you meet the outcomes of the unit of competency.

There is a section at the end of this Learner Guide that gives you the chance to test your own understanding of the content of this Unit before being assessed formally by your assessor. The Learning Activities and the Check your Understanding section of this Learner Guide are not formal assessments for this Unit.

What resources will I need to complete this unit?To complete this unit, certain resources are required. These resources are easily found in a workplace. If you are not in a workplace, your trainer will make sure you can obtain the required resources, and experience a real workplace environment.

Here is a suggested list of resources. Your trainer may also add any other relevant resources.

examples of planning documentation, procedures and work instructions used in the resources and infrastructure industries

examples of relevant signs, tags, markers and tapes

examples of resource and infrastructure industries written documentation that are required to be completed for specific tasks

examples of resource and infrastructure industries equipment and systems operating procedures, emergency rules, site specific procedures, fault finding procedures

safe work procedures manufacturer’s instructions codes of practice personal protective clothing workplace warnings and notices relevant workplace maps and plans environment management plan


IntroductionThroughout the construction industry, it is essential that all types of works need to be erected at a level and even to a certain height. As an example, if buildings are not built level, tables and chairs would slide from one end of a room to the other. If drains and pipes are not put in with the right slope, water will not run to the point intended.

Levelling may be done by various processes and with different instruments by which elevations of points or differences in elevation are determined.

Levelling is a measurement process. It is about how to transfer a height from one point to another point, or to compare the height of one mark to the height of another mark, or to transfer a height from a written plan to an actual work site.

In this learning guide you will be introduced to various terms and practices. To help these make more sense to you, visit a work site and locate these or use the tools discussed. For example, when we talk about datums or benchmarks, see if you can locate one at a worksite

Levelling is a very practical skill and it is best learnt by doing. Practice will be required to develop the level of accuracy and precision required in these tasks. Patience also assists in this process.

When undertaking levelling tasks, you will often be required to work as part of a team. Many types of levelling equipment require more than one operator, especially when vast distances are involved. Good communication is required to make sure these processes are carried out efficiently.

Work activitiesIn this role you will be doing work generally involving the levelling materials in civil works situations such as in the building of roads where the levelling of surfaces is critical to the quality of the finished job, effectiveness of the construction and the cost control on the use of materials.

Before doing any tasks you must also comply with any documentation relevant to the task at hand and you must understand the work instructions given to you. These will vary greatly depending on the industry you will be working in.

If you are unsure about any instructions, ask your supervisor to clarify them. You will work with greater accuracy when you understand your work instructions clearly.

The type of basic levelling you perform will depend on the work instruction you have been given. You may be asked to work on roadworks, community sub division or drainage works.


Compliance documentationBe aware of the work place compliance documentation that covers your work in levelling; that is - what it is, what it says, and where it is located.

Compliance documentation at your workplace may include:

legislative, organisation and site requirements and procedures

manufacture’s guidelines and specifications (this will be important when you use levelling equipment)

Australian standards codes of practice Employment and workplace relations

legislation Equal Employment Opportunity and

Disability Discrimination legislation environmental protection policies project or worksite traffic management

plan (this will have information on any signage required)

site safety plan

The documentation at your worksite may have different names to these. If you are unsure, check with your trainer or supervisor.

You may have been shown or told where these are located at your induction. Generally documentation is located on the company intranet. Familiarise yourself with these documents, where they are kept, and what the requirements are.

Worksite safety plans are developed in the planning stages of a project to make sure the workers, contractors and the general public are kept safe. Safety issues that will be covered in workplace documentation can include:

site emergency procedures (first aid stations and assembly points)

required personal protective equipment (PPE)

safe work procedures which may include: Standard Operating Procedures (SOPs) Job Safety Analyses (JSAs) or Safe

Work Method Statement (SWMS) Safety Data Sheets (SDSs) site hazards and risk assessments site access (entry and exit procedures)


Safety and hazardsThe safety of workers and the identification of hazards should be part of the planning and design process. These tie in with compliance documentation and developing safe work procedures for the safety of all workers on site.

Some examples of hazards that may be involved in your work could be:

uneven/unstable terrain overhead and underground services excavations and embankments traffic and mobile plant

For safety reasons you need to make sure that you know the safety requirements that are in the site safety plan and the workplace policies and procedures. This will keep you safe and your work colleagues safe while you do your job.

Training should be provided to you before you use any of the equipment so that you know how to operate the equipment safely and do not injure yourself or others.

SignageBefore you begin a task check the project or site traffic management plan for any signage requirements you may have to set up before beginning a task.

Signage provides useful warning of potential hazards and reminders of safety requirements. Signs should be displayed at all hazardous locations to warn workers of the nature of local risk and how this can be avoided.

The traffic management plan will be different for each project and work area, but may contain information such as:

Details of traffic routes used by construction vehicles.

The number and type of vehicles to be used in the construction of the project, and their movements to, from and within the site per day.

Speed limits to be observed along routes to and from the site.

Behaviour requirements for vehicle drivers to and from the site and within the site.

Communication bandwidth

From the project traffic management plan, you will be able to:

identify which signs need to be used, and where the signs should be located


Plant, tools, equipment It is important to use the right levelling equipment for the job. Not all levelling equipment will provide accurate information for the same tasks. So you need to select the equipment for the task it was intended. Levelling tools will be discussed specifically in the next section.

When using a tool for a task it is not designed for, you may damage the tool or hurt yourself or others. Choosing the right piece of equipment will help you work with greater safety and efficiency. Only use equipment for what it was originally designed to do.

You should also prepare for tasks by putting on suitable personal protective equipment. Appropriate protective equipment must always be provided by employers and it is your duty of care to use it.

Examples of personal protective equipment include:

goggles or safety spectacles safety boots with steel toe caps overalls or other well-fitted clothing safety vests appropriate for the category

of site (e.g. rail or highways)

Before using tools check that they work properly and are not damaged. Pre-start checks are carried out equipment is started. What is involved with the pre-start check will vary with individual contractor, but should be according to a written check list which may be part of the daily report.

There will also be ‘tolerance’ checks that you will need to perform on equipment to check it is accurate, and this will be discussed later in the learner guide.

Any defects should be reported to your supervisor.

You should also check the working condition of non-mechanical equipment. For example, if you are using a hammer, giving it a quick look over to check its condition could prevent a situation such as the end of the hammer flying off and hurting someone.

Your workplace should have a system in place where all equipment is scheduled for regular maintenance. If equipment is due for a maintenance check then you must follow workplace procedures, including notifying the appropriate person, for this to be done.


If a service is needed, take it to someone who is qualified. Never try to service equipment yourself unless you are authorised to do so.


Environmental protection requirements

You will need to take precautions in the planning process to prevent any adverse environmental effects occurring during the work stage and protect the surrounding environment of the worksite. Otherwise heavy penalties could apply. You must follow all environmental regulations when planning and carrying out work. These are identified in the project environmental management plan.

The environmental protection plan should provide detail on how to deal with waste. There are different types of waste including:

general waste recycling waste – glass, aluminum, soil infectious waste – blood, needles,

bandages, human waste hazardous waste – chemicals and

harmful substances

In most cases waste is treated in the following way:

general waste is put in a rubbish bin recycling waste is put in a specially

marked area or container infectious and hazardous waste should

only be handled using personal protective equipment such as gloves, masks and goggles (specialised help may be needed to do this task, so you should always consult your supervisor)

Check the environmental management plan for your work site for specific instructions.

There are several things to be aware of in relation to environmental issues when undertaking levelling activities at a worksite:

waste management water quality protection noise vibration dust and clean-up management

Types of levelling workThe types of levelling work you may carry out could include:

transferring levels or heights for formwork

checking heights or depths of excavations for earthwork

checking ‘crossfall’ for a roadwork checking inlet and outlet levels of

pipework so water flows correctly and also check depth of pipes are laid in the trenches are correct

having the correct fall (or incline) for drainage works, again so water flows downhill and is directed appropriately

positioning offsets relative to the area where work is being carried out

putting in recovery pegs if original levels have been damaged or pegs removed


Terminology

Vertical and Horizontal

We will be talking about vertical and horizontal levels throughout the guide. The following diagram shows what we mean when we talk about vertical and horizontal.

Vertical

Horizontal

Datum

A datum is used as a starting point for calculations because its height is known. Check with the local council that a fixed datum is still relevant or in use.

A datum can be a ‘reference’ point that is set out in the project plans. In this case it may be a certain survey peg or marker, the corner boundary point of the worksite, a marker on a power pole and so on.

Bench mark

A bench mark (BM) is related to the datum – as it is the term given to a point of known height above a datum to which the height of other points can be referred. For example, a benchmark can be a stainless steel pin embedded in a concrete block set into the ground. The datum and benchmark may or may not be within the boundary of the construction area.

Levelling equipment The tools and equipment that you will use for levelling may include:

spirit levels laser levels string lines tape measures automatic levels survey pegs levelling staffs plumb bobs optical square inclinometers batter pegs/boards wooded/steel pegs straight edges hammers chalk line

Some of the technical equipment is sensitive and needs to be handled with care when packing, unpacking and transporting.


Selecting correct tool for the job

spirit levels These are tools with a straight edge and a levelling bubble that moves to show when the vertical or horizontal measure is level. You can watch a video at http://www.dailymotion.com/video/xitm6x_how-to-use-a-precision-spirit-level_lifestyle?search_algo=2 on how to use a precision spirit level.

laser levels These are becoming more popular and they give a non-stop level mark through a laser transmitter and receiver.

string lines A string line is what it says – a line from a length of string, the string needs to be pulled tight and not caught up on any obstructions. Other tools are used to get the string to the right height.

tape measures A tape measure is used for measuring tasks

automatic levels Some automatic levels use laser to show the height or depth. Some include a GPS based on the machine set up

survey pegs These pegs are hammered into the ground to show levels, offsets, slopes and information from plans. They can be made of wood or metal.

levelling staffs or survey rods

There are many types of levelling staffs or rods. Some may be in one piece or they may be able to adjust their length by telescoping sections inside each other. Markings may be on one side or both sides. A good explanation of the levelling staff can be found at http://www.levelling.uhi.ac.uk/tutorial1_7.html

The levelling staff is used with the ‘dumpy’ level – the surveying tool you will see many surveyors using to look through to the levelling staff.

‘How to read a levelling 'E' type staff’ is a useful video to watch at http://www.youtube.com/watch?v=o8d-5S1z0e8

plumb bobs This is a heavy weight that hangs from a particular point to show vertical alignment.

optical square This is used to check angles

inclinometers This is used to check the slope of an area by being placed at the base of the slope

batter pegs/boards This is a peg driven into the ground or a board used to show the limits of an earth slope


http://www.youtube.com/watch?v=o8d-5S1z0e8

http://www.levelling.uhi.ac.uk/tutorial1_7.html

http://www.dailymotion.com/video/xitm6x_how-to-use-a-precision-spirit-level_lifestyle?search_algo=2

http://www.dailymotion.com/video/xitm6x_how-to-use-a-precision-spirit-level_lifestyle?search_algo=2

wooded/steel pegs Wooden pegs are used for temporary markers and steel pegs are used more for long term marking

straight edges/T-square Used to check an angle in a mark-up

hammers Used to put pegs etc. in place as markers

chalk line This is a string line that has had chalk run over it so that when it is ‘snapped’ the string hits the object such as a wall and marks a straight line on it

theodolite Is like a rotating telescope used to measure horizontal and vertical angles. If you need to use one on your worksite, watch the video ‘How to set up a theodolite –UWS’ on http://www.dailymotion.com/video/x9llh6_how-to-set-up-a-theodolite-uws_tech

Checking equipment for serviceabilityWhen using levelling equipment it is important that it is accurate so that it can give readings are that correct. Otherwise buildings will be built at the wrong height or trenches won’t be dug to the correct depth. Equipment may not be accurate because it has been knocked as it is packed or unpacked or as it was being carried or transported. Care should always be taken with levelling equipment and following manufacturer’s instructions for how to move these so that they continue to give accurate levels.

Faults that are not discovered through checking will lead you to incorrect readings and construction that is not according to plan specifications.

Levelling equipment and devices need to be maintained according to manufacturer’s instructions. This will make sure their high level of accuracy is maintained.

Some levelling equipment will need to be checked by qualified specialists are re-calibrated so they give accurate levels.


http://www.dailymotion.com/video/x9llh6_how-to-set-up-a-theodolite-uws_tech

http://www.dailymotion.com/video/x9llh6_how-to-set-up-a-theodolite-uws_tech

30m 30m

A BC D

10m

70m

Levelling equipment can be checked using:

two peg test reverse reading for spirit level

Two peg test

This test is commonly used for levelling tools such as automatic levels. At the most basic level the test is conducted as follows:

Step 1 – Chose a flat area and measure out two pegs and place the automatic level in the exact centre. For example, place the two pegs 60 metres apart and place the level tool at 30 metres in the centre of the two pegs.

Step 2 – Take the automatic level at point from C to A and from C to B. Write down the heights.

Step 3 – Move the level from point C to point D and take the heights of point A and B again.

Step 4 – Compare the heights to see if the automatic level is accurate or needs adjusting.

Example: Two peg test


Reverse readings

This test is used for levelling tools that use a bubble to show level, such as spirit levels.

The test performed to check the accuracy of this type of level is called ‘reverse readings’. It is a test to check whether the level indicates a truly horizontal surface is, in fact, level

To do this, the level is placed on surface that can be adjusted until the bubble in the level is centred. The spirit level is then rotated 180°. If the spirit level is accurate, the bubble will again be centred.

If the bubble is not centred an adjustment of the spirit level is needed or the tool may need to be cleaned or replaced, (for example, look for a build-up on the level bottom flat edge of the spirit level).


LEARNING ACTIVITY 11.1 What compliance documentation do you need to be aware of/apply when doing levelling work?

Where is this documentation stored in your organisation or worksite?

1.2 What levelling equipment do you use in your workplace and what is each used for?

Take a photo or draw a rough sketch of each of the tools and write a short explanation about what they are used for.

Levelling Equipment

Name and sketch/photoWhat is this piece of equipment used for?


1.3 Explain what ‘level’ work means and give three (3) examples of types of levelling work that could be done.

1.4 Explain in your own words the meaning of the following terms.

Levelling term Meaning

Datum

Bench mark


1.5 Select two (2) pieces of levelling equipment used at your worksite. Demonstrate to your trainer how you check a level for accuracy?


Establish offsets for civil works

Survey controlsThe connection between a construction plan and the real world of a construction site it represents must be clear and accurate.

To be able to relate a plan to actual land and construction, the mapmaker locates the known position (latitude, longitude and height) of a feature that can be seen clearly on the map. These positions are known as the survey control, and they are used to establish offsets for civil works.

Before you establish offsets, make sure you know what the survey control feature or features are so that the offsets are set in the correct position according to plan.

Establish offset and recover pegsOffset pegs are used to re- establish the original lines and design points of the proposed structure. This is because, for example when doing foundation constructions, the corner pegs will be lost once excavation starts. To avoid this, extra pegs called offset pegs are used. It is good practice to install all offset pegs within the construction site boundary.

Check site plans to identify where these offsets need to be placed and at what distance.

Example: Offset pegs in a foundation construction.


corner peg

offset peg

Re-establish earthwork and pavement control linesThe depth of earthworks or placing materials on top of original ground line will mean that levels will have changed.

Once the level after construction work is higher or lower than the starting point, control lines will need to be re-established. It is important when doing this that the same datum or benchmark be used from preliminary surveys is used to re-establish the earthwork and payment control lines. It is therefore important that this control point remains stable and unmoved throughout the construction to be used as a reference point for these re-establishment calculations.

The time and cost that is required for resetting these control lines can be reduced if easy to use reference markers are set before construction is started.

It is important that these re-established markers are placed in stable, undisturbed ground.

Establish drainage offsets from survey controlDrainage offsets are established using similar principles. Drainage offset pegs should be installed prior to beginning drain excavation, according to site plans.

Offset pegs are positioned and located in an area least likely to be disturbed from the trenching work. This distance to the offset peg should be read from the site plan; and the offset distances for the pegs should be kept the same.

The offset distance should also take account of where excavated material will be placed and the space required for the free movement of plant.


LEARNING ACTIVITY 22.1 Explain to your trainer, using a worksite plan, where the survey controls are.

Make notes if needed to clarify your explanation.

2.2 Explain and demonstrate to your trainer how you: establish offset and recover pegs from survey controls re-establish earthwork or pavement control lines from offsets or recovery pegs establish drainage offsets from survey control

Make notes if needed to clarify your explanation.


Setting up and using levelsReading levels from plans or instructionsPlans are technical drawings drawn to scale. They include all the details about the dimensions of the design for what is being constructed. They include all aspects of a project from less technical aspects such as a map of the site to cross-sectional plans and longitudinal plans.

Your work will involve reading heights (and depths) of construction or structures from project plans or instructions. It will be your task to take these and make them happen in reality.

All plans can be aligned to a worksite using a predetermined point called the datum. As mentioned previously, a datum is the ‘initial point’ of reference, which has a set latitude, longitude and elevation on the worksite. This is one of the most important reference points on any plan. The location of the datum can be represented on plans in a number of ways but is generally shown like the following example:

Example of a datum symbol

A datum is on a plan so there is always a reference to find out the exact position of everything that features on the plan.

The best way to read a level from a plan is to locate a real plan of an existing construction and look at the levels from the plan and see how they look in the actual real construction. Do this for three or four different measurements on the plan to get familiar with looking at the paper version and what it then looks like in reality when construction has been completed.

Set up and use levelling instruments It is important that levelling instruments are used according to manufacturer’s instructions to make sure all levels measured are accurate.

Some levelling tools require special setting up. Laser levelling equipment requires special care.

Common error sources

level rod not vertical or not held straight levelling rod not fully extended or

incorrect length level instrument not level instrument out of adjustment environment – wind or heat incorrect reading, incorrect recording


Transfer heights from the known to the requiredIn your work you will need to look at heights on plans and transfer these to the actual work site. The height will be marked on the plan and you will need to transfer this reading to the ‘real world’. At times you may also have to do the reverse; you may have to create plans from an existing building or worksite, taking measurements and marking these on a plan.

When transferring heights:

make sure you read the plan correctly use the correct measurement method,

mm or metres are normally standard but double check

start at the right point indicated on the plan

if you are unsure about anything on the plan check with your supervisor

start with the reference point (e.g. datum or benchmark) as the starting point for measurements

some levelling tools become inaccurate over longer distances so care should be taken with selecting the correct method and tool for the task

always consult your supervisor or trainer when unsure about methods or tools


Datum/benchmark

Datum/benchmark

Document results of levelling procedure

Open and close traverse

Open traverse

An open traverse is a series of linked traverse lines as outlined below, which do not return to the starting point.

Closed traverse

Always start and end a closed traverse on the same datum/benchmark.

More reliable as finishing on the same point allows for error checking.


AB

C

DBS FS

BS FSBS FS

Rise and fall methods of reduction

This is a method of recording heights taken in levelling, such as an open or close traverse.

As the levels are taken at different sites, using the example below from point A to point D, the heights rise and fall. This provides the basics behind rise and fall method for finding out elevation of unknown points.

So, the difference between the staff level readings shows a rise or a fall at the point is smaller or greater than the point before it.

A simplified example of this is outlined below.

Backsight (BS) Foresight (FS) Level

A From A measure B a to b = rise

B From B measure A From B measure C b to c = rise

C From C measure B From C measure D c to d = fall

D From D measure C

A backsight is a reading from where you have come from, and a foresight reading is in front of you – where you haven’t been yet.

When using this method double check all measurements and calculations. Make sure readings are entered into the correct space. Check mathematical calculations while still on site.


As measurements are never 100% accurate there is a ‘tolerance’ allowance for error. This is the amount of error that is acceptable. This allowance should be set by the project coordinator or as an acceptable level by the worksite and should be checked.


Mathematical calculations

It is important to get the calculations used in levelling correct. This is especially important when you are doing an open or closed traverse or the rise and fall method of reduction as these involve a series of calculations and if one calculation is incorrect then the series will not be correct.

Example:

You are at a worksite when the council has a temporary benchmark of 20.5m.

You have four locations for measurements.

One of the first tasks is to find out the height of the temporary benchmark plus the height of the instrument you are using.

This is done taking a ‘backsight’. In this case the backsight is 1.5m.

Temporary bench mark: 20.5m

Backsight: 1.5m

Instrument height: 20.5 + 1.5 = 22 m

Readings taken around the site recorded as follows:

Location Reading

A 1.55m

B 1.75m

C 1.86m

D 1.45m

With the readings, now you need to ‘reduce’ the levels. ‘Reduce’ the levels means that what you are doing is finding out the height of the ground at the base or bottoms of the staff.

As you know the height of the instrument level all you have to do is subtract the staff reading to find out the actual height of the level on the ground.

This can be recorded in the table as seen below.

Temporary bench mark: 20.5m

Backsight: 1.5m

Instrument height: 20.5 + 1.5 = 22 m

Location Reading ‘Reduced’

A 1.55m 22 – 1.55 = 20.45m

B 1.75m 22 – 1.75 = 20.25m

C 1.86m 22 – 1.86 = 20.14m

D 1.45m 22 – 1.45 = 20.55m


When recording heights and performing mathematical calculations, make sure:

readings are checked carefully before marking the position

take a second reading to be sure if you are unsure of a reading, you may

want a colleague to double check for you

you don’t ‘transpose’ numbers. This is done by changing the order of the numbers from a reading – for example writing 2.32 as 2.23, where the 2 and 3 after the decimal point are swapped around

A good example can be seen in the video called ‘Levelling Example’ at http://www.youtube.com/watch?v=1qDQNVemX4g. This is an American video so they use feet instead of metres but the video does a good job of explaining how to find the elevation of a set point which is at the end of an open traverse, when provided the elevation of a point at the beginning of the traverse, and the foresight and backsight measurements.


http://www.youtube.com/watch?v=1qDQNVemX4g

http://www.youtube.com/watch?v=1qDQNVemX4g

LEARNING ACTIVITY 3

3.1 Explain the difference between an open traverse and a close traverse levelling.

3.2 Demonstrate or explain the rise and fall method of reduction.Make notes if needed to clarify your explanation.

3.3 How do you make sure that you have accurate recording of results of each levelling procedure?


Clean upA workplace should be kept clean during operations and also cleaned up once operations have been completed. The benefits of a clean and tidy workplace include:

injuries in the workplace can be prevented

positive attitude is created for health and safety issues

work efficiency and employee morale is improved

work productivity can be increased

Environmental protection requirementsWhen undertaking your work activities you must take into account any environmental protection requirements. For example, when you are cleaning up after work activities you must dispose of waste according to workplace policy. This will involve recycling materials such as paper, plastic, wood and steel, while safely disposing of material that may require special attention such as liquid waste.

You should obtain these environmental requirements from the project environmental management plan at your workplace and speak to your supervisor regarding these requirements.

Keeping equipment cleanYou should maintain your equipment in a good condition. You have a greater chance of noticing any defects and any maintenance required when you clean equipment after use. After you have finished with equipment, always return it to its allocated place so it can be easily found when required.

Maintenance of equipmentThere will be workplace documentation that states when equipment is to be serviced or checked. Basic maintenance requires that equipment is cleaned and checked for any faults and that faults are reported to your supervisor.

Injuries can occur when tools are not maintained correctly.


Disposing of wasteGenerally you will be asked to dispose of materials during the cleaning up stage of a job when it has been completed.

During clean-up there are environmental controls which organisations must follow or face punishment such as fines or even jail terms.

Your organisation must have the policy and procedures in place to correctly dispose of all the types of waste that are produced. For example, some materials will be:

recycled disposed of as rubbish used for future jobs

There will be a project environmental management plan that will direct how to dispose of materials.

If there is a problem with a system that you are asked to follow, you must notify the appropriate person, such as your supervisor or manager. It is everyone’s responsibility to continually improve environmental methods and procedures in the workplace while following all environmental laws.

Storing equipmentStoring equipment when not in use is also a part of safe work practices. You should always return equipment to its designated place after use. It will not then get in the way of others working in the area or cause an accident. For example if an electric piece of equipment is left on a bench use it, it could:

be accidentally switched on and cause someone serious injury

be knocked off the bench and hurt someone

become a tripping hazard if the lead is left plugged in

be used by an unqualified operator


LEARNING ACTIVITY 44.1 What are the benefits of cleaning tools after use?

4.2 What should you do with waste (rubbish) at the end of the project?

4.3 How should levelling tools and equipment be cleaned and stored?


Check Your UnderstandingThis section of the Learner Guide contains the Check Your Understanding activities.

You should complete these activities when you have finished the training for this Unit to check that you have developed the skills and knowledge required to be found Competent in a formal assessment for this Unit.

If you have any difficulty in completing these activities, you should revise the content of this Learner Guide or ask your trainer for further assistance.


Knowledge questionsAnswer the following questions in the space provided.

1. Select three levelling tools and explain their characteristics and technical features.

2. Explain where you would find compliance documentation and safety requirements for levelling tasks?

3. Explain the importance of checking levelling equipment for serviceability.Explain what might be the outcome if readings are not correct?


4. Explain what might cause levelling equipment to become inaccurate?

5. What is the procedure for setting up an automatic level?

6. Explain in your own words the purpose of the following:

what recovery pegs are used for what offset pegs are used for what drainage offsets are used for


7. Explain why the offset and recovery pegs must be linked to the survey control.

8. What reports/records are you required to complete?

9. List some of the hazards you need to be aware of?


Practical ActivitiesYour assessor will provide you with instructions/documentation to complete an activity for you to demonstrate that you can carry out basic levelling.

1. Demonstrate a closed traverse using:

height of instrument

2. Demonstrate a closed traverse using:

rise and fall method of reduction

3. Conduct a two peg test with an automatic level.


4. Accurately record the results of a levelling procedure given to you by your trainer, using workplace documentation.

5. Demonstrate that you can transfer the heights from a project plan to the job.


Answers to learning activitiesLearning activity 1

1.1 What compliance documentation do you need to be aware of/apply when doing levelling work? Where is this documentation stored in your organisation or worksite?

Answer:Compliance documentation will include:

legislative, organisation and site requirements and procedures manufacture’s guidelines and specifications (this will be important when you use levelling

equipment) Australian standards codes of practice Employment and workplace relations legislation Equal Employment Opportunity and Disability Discrimination legislation environmental protection policies project traffic management plan (this will have information on any signage required) site safety plan

Documentations storage location will depend on the workplace.

1.2 What levelling equipment do you use in your workplace and what is each used for.

Take a photo or draw a rough sketch of each of the tools and write a short explanation about what they are used for.

Answer:Answer will depend on the levelling equipment used at the worksite. Answer should identify all equipment and give a clear indication of tasks carried out using the tools. Any photos should be clearly labelled.

1.3 Explain what ‘level’ work means and give three (3) examples of types of levelling work that could be done.

Answer:Levelling is a measurement process. It is about how to transfer a height from one point to another point, or to compare the height of one mark to the height of another mark, or to transfer a height from a written plan to an actual work site.

Levelling work may include:

transferring levels or heights for formwork checking heights or depths of excavations for earthwork


checking ‘crossfall’ for a roadwork checking inlet and outlet levels of pipework so water flows correctly and also check depth of

pipes are laid in the trenches are correct having the correct fall (or incline) for drainage works, again so water flows downhill and is

directed appropriately positioning offsets relative to the area where work is being carried out putting in recovery pegs if original levels have been damaged or pegs removed

1.4 Explain in your own words the meaning of the following terms.

Answer:Levelling term Meaning

Datum A datum is used as a starting point for calculations because its height is known. Check with the local council that a fixed datum is still relevant or in use.

A datum can be a ‘reference’ point that is set out in the project plans. In this case it may be a certain survey peg or marker, the corner boundary point of the worksite, a marker on a power pole and so on

Bench mark A bench mark (BM) is related to the datum – as it is the term given to a point of known height above a datum to which the height of other points can be referred.

For example, a benchmark can be a stainless steel pin embedded in a concrete block set into the ground.

1.5 Select two pieces of levelling equipment used at your worksite. Demonstrate to your trainer how you check a level for accuracy?

Answer:Answer will depend on equipment selected. May demonstrate the two peg test or reverse readings.

Learning activity 2

2.1 Explain to your trainer, using a worksite plan, where the survey controls are.

Answer:Answer will be specific to worksite plan selected.


2.2 Explain and demonstrate to your trainer how you:

establish offset and recover pegs from survey controls re-establish earthwork or pavement control lines from offsets or recovery pegs establish drainage offsets from survey control

Answer:Answer should include demonstration showing a clear understanding of the principles for establishing offsets for civil works.

Learning activity 33.1 Explain the difference between an open traverse and a close traverse levelling?

Answer:An open traverse is a series of linked traverse lines as outlined below, which do not return to the starting point.

A closed traverse always starts and ends on the same datum/benchmark.

3.2 Demonstrate or explain the rise and fall method of reduction.

Answer:Answer should show clear understanding of rise and fall method to find out elevation of unknown points.

3.3 How do you make sure that you have accurate recording of results of each levelling procedure?

Answer: check readings carefully before marking the position take a second reading to be sure ask a colleague to double check reading don’t ‘transpose’ numbers

Learning activity 4

4.1 What are the benefits of cleaning tools after use?

Answer:Equipment will be better maintained for future use, be accurate etc. There is also a greater chance of noticing any defects and any maintenance required when equipment is cleaned after use. Work is made easier for the next job or the next operator to use the equipment, thus increasing productivity and making everyone’s work a bit easier.


4.2 What should you do with waste (rubbish) at the end of the project?

Answer:Answer should reflect requirements of workplace policies and procedures in relation to waste. The answer should distinguish between recycled and general waste.

4.3 How should levelling tools and equipment be cleaned and stored?

Answer:Answer will be specific to the site procedure but should include the following or an equivalent:

according to manufacturer’s instructions and workplace procedures


RTO Name: RTO ID:

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