ISO 7078:2020

INTERNATIONAL ISO
STANDARD 7078
Second edition
2020-04
Buildings and civil engineering
works — Procedures for setting
out, measurement and surveying —
Vocabulary
Construction immobilière — Procédés pour l'implantation, le
mesurage et la topométrie — Vocabulaire
Reference number
ISO 7078:2020(E)
©
ISO 2020

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ISO 7078:2020(E)

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© ISO 2020
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ISO 7078:2020(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 General terms . 1
3.2 Quality of measurement . 6
3.3 Scales .10
3.4 Measuring tools .12
3.5 Measuring instruments and their parts .15
3.6 Methods of measuring .19
Bibliography .29
INDEX .30
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ISO 7078:2020(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 59, Buildings and civil engineering works,
Subcommittee SC 2, Terminology and harmonization of languages.
This second edition cancels and replaces the first edition (ISO 7078:1985), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— removal of diagrams describing traditional practices and statistical methods;
— renumbering of all entries;
— terms previously discussed in groups now separated and presented as individual entries.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
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ISO 7078:2020(E)

Introduction
This document has been revised to be compatible with the series of vocabularies being produced by
TC 59/SC 2 spanning across several domains within the construction sector. With the growth in the
number of international construction projects and the development of the international market for
construction products, there is an increasing need for an agreement on a common language across
disciplines.
The practical realization of dimensional accuracy in relation to buildings and civil engineering
works involves not only land surveyors and measuring technicians but also professionals engaged
in the different stages of the construction process. Further, the widespread use of optical measuring
instruments and associated electro-optical techniques, many of which make provision for automatic
communication of information, makes smooth communication between different professions
necessary. In order to promote such a communication agreement on terms and concepts used in setting
out, measurement and surveying is necessary. The purpose of this document is, therefore, to provide
a consistent language for use by the various professions involved in measurement in the construction
industry.
International preferred terms are listed in boldface type. Where a preferred term is specific to a
particular English-speaking country, e.g. the United States of America, etc., it is given below the
international preferred term and is annotated with the relevant country code. Where no preferred
terms are listed indicating usage in a specific geographical location, this signifies that the international
preferred term is the accepted term in the English-speaking countries. A term beneath the preferred
term not given in boldface type is an admitted (non-preferred) synonym. A country code is assigned to
an admitted term if it is specific to a particular English-speaking country.
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INTERNATIONAL STANDARD ISO 7078:2020(E)
Buildings and civil engineering works — Procedures for
setting out, measurement and surveying — Vocabulary
1 Scope
This document defines terms that are commonly used in procedures for setting out, measurement and
surveying in buildings and civil engineering works.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
NOTE ISO 6707-1 defines general terms for buildings and civil engineering works.
3.1 General terms
3.1.1
measurement
operation that has the object of determining the value of a quantity
[SOURCE: ISO 6707-1:2017, 3.5.1.22, modified — Note 1 to entry has been omitted.]
3.1.2
setting out
layout, US
laying out, US
establishment of marks and lines to define the position and level of the elements for the construction
work so that work can proceed with reference to them
[SOURCE: ISO 6707-2:2017, 3.3.13]
3.1.3
metrology
science of measurement (3.1.1) and its application
Note 1 to entry: Metrology includes all theoretical and practical aspects of measurement, whatever the
measurement uncertainty and field of application.
[SOURCE: ISO Guide 99:2007, 2.2]
3.1.4
geodesy
science of measurement (3.1.1) on or in the vicinity of the ground to determine form, dimensions and
the distribution of mass and fields of gravity on the earth or parts of it
Note 1 to entry: Surveying is the science of measurements necessary to determine the locations of points
(features) on or beneath the surface of the earth.
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Note 2 to entry: Where measurements cover such a large part of the earth’s surface that the curvature cannot be
ignored, then the operations are termed geodetic surveying or measuring.
3.1.5
photogrammetry
technique of measurement (3.1.1) using photographs, for example aerial photographs, to determine,
primarily, geometric properties such as size, location and form of objects
Note 1 to entry: Photogrammetric measurement is often used for mapping, but also has some engineering
applications.
3.1.6
measurand
quantity intended to be measured
Note 1 to entry: The measurand including the measuring system (3.1.19) and the conditions under which the
measurement (3.1.1) is carried out, might change the phenomenon, body, or substance such that the quantity
being measured may differ from the measurand as defined. In this case, adequate correction (3.2.15) is necessary.
[SOURCE: ISO/IEC Guide 99:2007, 2.3, modified — EXAMPLEs and NOTEs 2 to 4 have been omitted.]
3.1.7
measuring instrument
device used for making measurements (3.1.1) or for levelling (3.6.4)
Note 1 to entry: Measuring instruments are sometimes used in conjunction with one or more supplementary
devices.
3.1.8
measuring equipment
measuring instrument (3.1.7), material measure, software, measurement standard (3.1.14), reference
material, ancillary equipment (3.1.9) or auxiliary equipment (3.1.10) used in a measurement (3.1.1)
Note 1 to entry: The definition is necessarily wider than that of measuring instrument since it includes all the
devices used in a measurement.
[SOURCE: ISO 14978:2018, 3.5.1, modified — In the definition, “indicating” has been omitted from
beginning, and “ancillary equipment” has been inserted before “auxiliary equipment”; Note 2 to entry
has been omitted.]
3.1.9
ancillary equipment
equipment additional to the actual measuring instrument (3.1.7) used when carrying out
measurements (3.1.1)
EXAMPLE Pegs, sighting targets (3.6.67) and chalk marking lines.
3.1.10
auxiliary equipment
equipment that gives aid or support to a measuring instrument (3.1.7)
EXAMPLE Tripod.
3.1.11
measuring tool
simple measuring device
EXAMPLE Folding rule (3.4.5), measuring tape (3.4.1), square (3.4.12).
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3.1.12
indication
quantity value provided by a measuring instrument (3.1.7) or a measuring system (3.1.19)
Note 1 to entry: An indication may be presented in visual or acoustic form or may be transferred to another
device. An indication is often given by the position of a pointer on the display for analogue outputs, a displayed
or printed number for digital outputs, a code pattern for code outputs, or an assigned quantity value for material
measures.
Note 2 to entry: An indication and a corresponding value of the quantity being measured are not necessarily
values of quantities of the same kind.
[SOURCE: ISO/IEC Guide 99:2007, 4.1]
3.1.13
measurement result
set of quantity values being attributed to a measurand (3.1.6) together with other available relevant
information
Note 1 to entry: A measurement result generally contains “relevant information” about the set of quantity values,
such that some may be more representative of the measurand than others. This may be expressed in the form of
a probability density function (PDF).
Note 2 to entry: A measurement result is generally expressed as a single measured quantity value and a
measurement of uncertainty. If the measurement uncertainty is considered negligible for some purpose, the
measurement result may be expressed as a single measured quantity value. In many fields, this is the common
way of expressing a measurement result.
[SOURCE: ISO/IEC Guide 99:2007, 2.9, modified — NOTE 3 has been omitted.]
3.1.14
measurement standard
realization of the definition of a given quantity value and associated measurement (3.1.1) uncertainty,
used as a reference
[SOURCE: ISO Guide 99:2007, 5.1, modified — EXAMPLEs and NOTEs have been omitted.]
3.1.15
observation
act of measuring or otherwise determining the value of a property
[SOURCE: ISO 19109:2015, 4.16]
3.1.16
reading
part of an observation (3.1.15) which only involves the operator’s notations of values on a scale (3.3.1) or
other methods of recording values
3.1.17
measurement error
measured quantity value minus a reference quantity value
Note 1 to entry: Measurement error should not be confused with production error or mistake.
Note 2 to entry: A “reference quantity value” is a quantity value used as a basis for comparison.
[SOURCE: ISO/IEC Guide 99:2007, 2.16, modified — NOTE 1 has been omitted; NOTE 2 has been
renumbered as Note 1 to entry; new Note 2 to entry has been added.]
3.1.18
gauge
bar of steel or other suitable material of standard length, accurately made, for the purpose of checking
or verification of length measuring devices
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3.1.19
measuring system
set of one or more measuring instruments (3.1.7) and often other devices, including any reagent and
supply, assembled and adapted to give information used to generate measured quantity values within
specified intervals for quantities of specified kinds
Note 1 to entry: A measuring system may consist of only one measuring instrument.
[SOURCE: ISO/IEC Guide 99:2007, 3.2]
3.1.20
coordinate system
two-dimensional or three-dimensional reference system for defining the location points on a surface or
in space by means of distances (rectangular/Cartesian co-ordinates) or angles (angles co-ordinates) or
both (polar co-ordinates), with relation to designated angles or planes
Note 1 to entry: In land surveying, the x-axis may be in the direction of astronomic (true) north, magnetic north,
for example grid north, with the y-axis towards east. The z-axis points approximately upwards (towards the
zenith). In some countries, the x- and y- axes are reversed whilst in others E, N and H are used to refer to “East”,
“North” and “Height”.
Note 2 to entry: In building surveying, a local orthogonal system is often set up with the reference axes parallel
to the building axes or chosen at the convenience of the surveyor.
3.1.21
geodetic coordinate system
coordinate system (3.1.20) in which position is specified by geodetic latitude, geodetic longitude and (in
the three-dimensional case) ellipsoidal height (3.1.24)
[SOURCE: ISO 19130-1:2018, 3.22]
3.1.22
geographic coordinates
angular coordinates (angular distances) expressed as latitude and longitude to define a point on the
surface of the earth with reference to the equator and the meridian of Greenwich
3.1.23
level
value of the vertical dimension of a point above or below a defined reference
[SOURCE: ISO 6707-1:2017, 3.7.2.39]
3.1.24
height
vertical dimension above a horizontal reference level (3.1.23)
EXAMPLE Distance of a feature above the ground – height of a building.
[SOURCE: ISO 6707-1:2017, 3.7.2.36, modified — EXAMPLE has been added.]
3.1.25
global positioning system
GPS
instantiation of GNSS (3.1.26) controlled by the US Department of Defence
[SOURCE: ISO 15638-12:2014, 4.25]
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3.1.26
global navigation satellite system
GNSS
system that comprises several networks of satellites that transmit radio signals containing time and
distance data that can be picked up by a receiver, allowing the user to identify the location of the
receiver anywhere around the world
[SOURCE: ISO 15638-16:2014, 4.23, modified — The definition has been editorially updated.]
3.1.27
differential GPS
GNSS (3.1.26) application using only observations from GPS (3.1.25) (Navistar satellite system) and
additional reference point or reference network GPS observations
[SOURCE: ISO 9849:2017, 3.1.5.3]
3.1.28
real-time kinematic positioning
approach for a precise global positioning system (3.1.25), enabling the determination of a range signal
that can be resolved to a precision of less than 10 cm
Note 1 to entry: Facilitated by resolving the number of cycles in which the signal is transmitted and received by
the receiver.
3.1.29
differential GNSS
processing application within mobile GNSS receivers (3.5.27), using difference techniques of GNSS
(3.1.26) observations and additional reference point or reference network GNSS observations
Note 1 to entry: In differential GNSS applications correction data and additional information from a known
reference station are used by mobile rovers, enabling them to improve position accuracy from the 15 m nominal
GNSS accuracy to about 10 cm or less.
[SOURCE: ISO 9849:2017, 3.1.52, modified — The abbreviated term "DGNSS" has been omitted.]
3.1.30
testing of measuring instruments
procedures designed to determine whether a measuring instrument (3.1.7) satisfies requirements in
respect of one or more specified properties under specified conditions
3.1.31
calibration
operation that, under specified conditions, in a first step, establishes a relation between the quantity
values with measurement uncertainties provided by measurement standards (3.1.14) and corresponding
indications (3.1.12) with associated measurement uncertainties and, in a second step, uses this
information to establish a relation for obtaining a measurement result (3.1.13) from an indication (3.1.12)
Note 1 to entry: A calibration may be expressed by a statement, calibration function, calibration diagram,
calibration curve, or calibration table. In some cases, it may consist of an additive or multiplicative correction of
the indication with associated measurement uncertainty.
Note 2 to entry: Calibration should not be confused with adjustment of a measuring system (3.1.19), often
mistakenly called “self-calibration”, nor with verification of calibration.
Note 3 to entry: Often, the first step alone in the above definition is perceived as being calibration.
[SOURCE: ISO/IEC Guide 99:2007, 2.39]
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3.1.32
comparator
measuring equipment (3.1.8) used in addition to a standard for calibration (3.1.31) of measuring
instruments (3.1.7)
EXAMPLE 1 Comparing a measuring tape (3.4.1) or an EDM (3.5.6) with a bar standard.
EXAMPLE 2 For the determination of the accuracy of an angular scale in a theodolite (3.5.4).
EXAMPLE 3 In photogrammetry (3.1.5), for determining co-ordinates on photographs using stereocomparators.
3.2 Quality of measurement
3.2.1
true value
value which characterizes a quantity perfectly defined in the conditions that exist when that quantity
is considered
Note 1 to entry: It is an ideal value which can be observed only if all causes of measurement error (3.1.17) are
eliminated.
[SOURCE: ISO 772:2011, 7.9]
3.2.2
influence quantity
quantity that, in a direct measurement (3.1.1), does not affect the quantity that is actually measured, but
affects the relation between the indication (3.1.12) and the measurement result (3.1.13)
EXAMPLE Measuring tape (3.4.1) temperature when measuring distances.
[SOURCE: ISO/IEC Guide 99:2007, modified — EXAMPLEs and NOTEs have been omitted; a new
EXAMPLE has been added.]
3.2.3
measurement accuracy
accuracy of measurement
closeness of agreement between a measured quantity value and a true quantity value of a measurand
(3.1.6)
Note 1 to entry: The concept ‘measurement accuracy’ is not a quantity and is not given a numerical quantity
value. A measurement (3.1.1) is said to be more accurate when it offers a smaller measurement error (3.1.17)
Note 2 to entry: The term ‘measurement accuracy’ should not be used for measurement trueness and the term
‘measurement precision’ should not be used for ‘measurement accuracy’ which is related to both these concepts.
Note 3 to entry: ‘Measurement accuracy’ is sometimes understood as agreement between measured quantity
values that are being attributed to the measurand.
[SOURCE: ISO/IEC Guide 99:2007, 2.13]
3.2.4
precision of measurement
closeness of agreement between independent measurement results (3.1.13) obtained under stipulated
conditions
Note 1 to entry: The degree of precision is expressed numerically by the statistical measures of imprecision of
measurements (3.1.1), such as standard deviation (3.2.22), that are inversely related to precision.
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3.2.5
accuracy class
class of measuring instruments (3.1.7) or measuring systems (3.1.19) that meet stated metrological
requirements that are intended to keep measurement errors (3.1.17) or instrumental measurement
(3.1.1) uncertainties within specified limits under specified operating conditions
Note 1 to entry: An accuracy class is usually denoted by a number or symbol adopted by convention.
Note 2 to entry: Accuracy class applies to material measures.
[SOURCE: ISO/IEC Guide 99:2007, 4.25]
3.2.6
repeatability of results of measurement
closeness of the agreement between the results of successive measurements (3.1.1) of the same
measurand (3.1.6) carried out under the same conditions of measurement
Note 1 to entry: These conditions are called repeatability conditions.
Note 2 to entry: Repeatability conditions include: the same measurement procedure; the same observer; the
same measuring instrument (3.1.7), used under the same conditions; the same location; repetition over a short
period of time.
Note 3 to entry: Repeatability may be expressed quantitatively in terms of the dispersion characteristics of the
results.
[SOURCE: ISO/IEC Guide 98-3:2008, B.2.15]
3.2.7
reproducibility condition of measurement
condition of measurement (3.1.1), out of a set of conditions that includes different locations, operators,
measuring systems (3.1.19), and replicate measurements on the same or similar objects
Note 1 to entry: The different measuring systems may use different measurement procedures.
Note 2 to entry: A specification should give the conditions changed and unchanged, to the extent practical.
[SOURCE: ISO/IEC Guide 99:2007, 2.24]
3.2.8
systematic measurement error
component of measurement error (3.1.17) that in replicate measurements (3.1.1) remains constant or
varies in a predictable way when the conditions change
Note 1 to entry: A reference quantity value for a systematic reference error is a true quantity value, or a measured
quantity value of a measurement standard (3.1.14) of negligible measurement uncertainty, or a conventional
quantity value.
Note 2 to entry: Systematic measurement error, and its causes, can be known or unknown. A correction (3.2.15)
can be applied to compensate for a known systematic measurement error.
Note 3 to entry: Systematic measurement error equals measurement error minus random measurement error.
[SOURCE: ISO/IEC Guide 99:2007, 2.17]
3.2.9
random error
result of a measurement (3.1.1) minus the mean that would result from an infinite number of
measurements of the same measurand (3.1.6) carried out under repeatability conditions
Note 1 to entry: Random error is equal to error minus systematic measurement error (3.2.8).
Note 2 to entry: Because only a finite number of measurements can be made, it is possible to determine only an
estimate of random error.
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[SOURCE: ISO/IEC Guide 98-3:2008, B.2.21]
3.2.10
total measuring error
whole measurement error (3.1.17) which consists of a combination of the random error (3.2.9) and the
systematic error (3.2.8)
3.2.11
closing error
error of closure
amount by which the value of one or more quantities obtained by surveying operations fails to agree
with a fixed or theoretical value of the same quantities
Note 1 to entry: In traversing (3.6.39), this can, for example, be the amounts by which the computed, but not
adjusted, coordinates of the end measuring point (3.6.50) of a traverse fail to agree with the given coordinates of
that measuring point.
3.2.12
discrepancy
difference between results of duplicate or comparable measures of a quantity; or difference in computed
values of a quantity obtained by different processes using data from the same survey
3.2.13
adjustment calculation
calculation process designed to distribute discrepancies due to the existence of redundant observations
(3.1.15) when measurement (3.1.1) is carried out according to certain rules, for example the least squares
method (3.2.14)
Note 1 to entry: A redundant observation is any observation which exceeds the number of observations which
are necessary for an unambiguous determination of the value of a quantity.
3.2.14
least squares method
obtaining true measurement values by minimizing the sum of the squares of the deviations from the
expected values
Note 1 to entry: Measurements are adjusted so that the sum of the squares of the differences between the
observed and adjusted values are minimized.
3.2.15
correction
value added algebraically to the uncorrected result of a measurement (3.1.1) to compensate for
systematic measurement error (3.2.8)
Note 1 to entry: The correction is equal to the negative of the estimated systematic error.
Note 2 to entry: Since the systematic error cannot be known perfectly, the compensation cannot be complete.
[SOURCE: ISO/IEC Guide 98-3:2008, B.2.23]
3.2.16
arithmetic mean
sum of measured values divided by the number of values
[SOURCE: ISO/IEC Guide 98-3:2008, C.2.19, modified – Notes 1 and 2 to entry has been omitted; the
admitted term "average" has been omitted.]
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3.2.17
weight of measurement
number which expresses the degree of confidence in the result of a measurement (3.1.1) of a certain
quantity in comparison with the results of another measurement of the same quantity
EXAMPLE 1 When using different types of measuring instruments (3.1.7).
EXAMPLE 2 Ratio of the reliability of various quantities in adjustment calculations (3.2.14), when determining
co-ordinates in triangulation (3.6.37) nets.
Note 1 to entry: The higher the number, the greater the confidence.
3.2.18
arithmetic weighted mean
sum of the products of each measured value and its weight of measurement (3.2.17) (which can be
positive or zero) divided by the sum of the weights of measurement
3.2.19
dispersion
scatter of the measured values obtained in a set of measurements (3.1.1) of a quantity
3.2.20
range
difference between the greatest and least values of a number of observations (3.1.15)
[SOURCE: ISO 1213-2:2016, 3.173]
3.2.21
variance
for any sample, average of the squares of the deviations from the mean
3.2.22
standard deviation
positive square root of the variance (3.2.21)
Note 1 to entry: For a set of data standard deviation is calculated as the square root of the average of the squares
of the deviations from the mean.
3.2.23
normal distribution
Laplace-Gauss distribution
symmetrical “bell shaped” density distribution which is fully defined by its mean and standard deviation
(3.2.22)
3.2.24
root mean squared error
square root of the mean
...