Units

CRS [Home-Map], Units tab, lets you set your preferred units of measurement to any of a range of metric or imperial measures. When entering coordinates or measuring graphics, the preferred units will be used, unless you specify otherwise by appending the unit identifier to the number.

Whenever you type units in SIS, you can:

Example:

If the current set units were millimetres (mm), you could type 4 metres in any of the following ways:

4000
4m
.004km
13.13´

etc.

Selecting Units

When you select one of the Units drop-down boxes, you will see a list of the available units. The units are listed using their specifier. You must use this specifier when typing units. For example, included in linear units are millimetres, centimetres, metres and kilometres. When you give dimensions using these units, you type mm, cm, m or km: for example 43mm, .043m.

When the required unit has been selected, select the required precision (number of decimal places) from the Places drop-down box.

Note: The entry before the colon (:) in each case in the following list is the specifier of the unit as shown in the Coordinate Reference Systems dialog, Units tab Linear, Area, Volume and Angle drop-down boxes. The entry in italics following the colon is the EPSG reference. See Note at the bottom of this page.

Linear
Area
Volume
Angle

Name: m

EPSG: metre

Type: length unit

Notes: also known as International metre

Ref: ISO 1000

Source: EPSG

Unit: metre

Multiplication factor: 1

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Name: km

EPSG: kilometre

Type: length unit

Notes:

Ref: ISO 1000

Source: EPSG

Unit: metre

Multiplication factor: 1000

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Name: foot

EPSG: foot

Type: length unit

Notes: 6 feet

Ref: ISO; 1958

Source: EPSG

Unit: metre

Multiplication factor: 0.3048

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Name: yd

EPSG: British yard (Benoit 1895B)

Type: length unit

Notes: G Bomford “Geodesy” 2nd edition 1962; after J S Clark “Remeasurement of the Old Length Standards”; Empire Survey Review, no. 90; 1953

Ref: G Bomford “Geodesy” 2nd edition 1962; after J S Clark “Remeasurement of the Old Length Standards”; Empire Survey Review, no. 90

Source: EPSG

Unit: metre

Multiplication factor: 0.914399204289812

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Name: fathom

EPSG: fathom

Type: length unit

Notes: 6 feet

Source: EPSG

Unit: metre

Multiplication factor: 1.8288

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Name: mile

EPSG: Statute mile

Type: length unit

Notes: 5280 feet

Ref: EPSG

Source: EPSG

Unit: metre

Multiplication factor: 1609.344

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Name: nautical mile

EPSG: nautical mile

Type: length unit

Source: EPSG

Unit: metre

Multiplication factor: 1852

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Name: ft (US)

EPSG: US Survey foot

Type: length unit

Notes: used in USA

Ref: EPSG

Source: EPSG

Unit: metre

Multiplication factor: 0.304800609601219 

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Name: ft (Cla)

EPSG: Clarke's foot

Type: length unit

Notes: assumes Clarke’s 1865 ratio of 1 British foot = 0.304797265 French legal metres applies to the international metre; used in older Australian, southern African and British West Indian mapping.

Ref:Australian Land Information Group,http://www.auslig.gov.au/geodesy/datums/

Source: EPSG

Unit: metre

Multiplication factor: 0.304797265 

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Name: Ind.ft (Cla)

EPSG: Indian foot (1975)

Type: length unit

Notes: Indian foot = 0.99999566 British feet (A R Clark 1865); British yard (3 feet) taken to be J S Clark’s 1865 value of 0.9144025m; rounded to 8 significant figures as 1 Ind ft = 0.3048995m; used in India since metrication.

Ref: G Bomford; “Geodesy”; 3rd edition 1975

Source: EPSG

Unit: metre

Multiplication factor: 0.3047995 

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Name: lk (Cla) 

EPSG: Clarke's link

Type: length unit

Notes: 1/100 Clarke's chain - Assumes Clarke’s 1865 ratio of 1 British foot = 0.304797265. French legal metres applies to the international metre; used in older Australian, southern African and British West Indian mapping.

Ref: Australian Land Information Group, http://www.auslig.gov.au/geodesy/datums/

Source: EPSG

Unit: metre

Multiplication factor: 0.2011661949 

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Name: lk (Ben)

EPSG: British link (Benoit 1895B)

Type: length unit

Notes: uses Benoit’s 1895 British yard-metre ratio as given by Bomford as 39.370113 inches per metre; used in West Malaysian mapping.

Ref: G Bomford; “Geodesy”; 3rd edition 1975

Source: EPSG

Unit: metre

Multiplication factor: 0.201167824943759 

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Name: lk (Sear)

EPSG: British link (Sears 1922)

Type: length unit

Notes: uses Sears’ 1922 British yard-metre ratio as given by Bomford as 39.370147 inches per metre; used in East Malaysian and older New Zealand mapping

Ref: G Bomford “Geodesy” 2nd edition 1962; after J S Clark “Remeasurement of the Old Length Standards”; Empire Survey Review, no. 90

Source: EPSG

Unit: metre

Multiplication factor: 0.20116767651215526 

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Name: ch (Ben)

EPSG: British chain (Sears 1922)

Type: length unit

Notes: uses Benoit’s 1895 British yard-metre ratio as given by Bomford as 39.370113 inches per metre; used in West Malaysian mapping

Ref: G Bomford “Geodesy” 2nd edition 1962; after J S Clark “Remeasurement of the Old Length Standards”; Empire Survey Review, no. 90

Source: EPSG

Unit: metre

Multiplication factor: 20.1167824943759 

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Name: ch (Sear)

EPSG: British chain (Sears 1922)

Type: length unit

Notes: uses Sears’ 1922 British yard-metre ratio as given by Bomford as 39.370113 inches per metre; used in East Malaysian and older New Zealand mapping

Ref: G Bomford “Geodesy” 2nd edition 1962; after J S Clark “Remeasurement of the Old Length Standards”; Empire Survey Review, no. 90

Source: EPSG

Unit: metre

Multiplication factor: 20.11677651215526 

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Name: yd (Sear)

EPSG: British yard (Sears 1922)

Type: length unit

Notes: uses Sears’ 1922 British yard-metre ratio as given by Bomford as 39.370113 inches per metre; used in East Malaysian and older New Zealand mapping

Ref: G Bomford “Geodesy” 2nd edition 1962; after J S Clark “Remeasurement of the Old Length Standards”; Empire Survey Review, no. 90

Source: EPSG

Unit: metre

Multiplication factor: 0.914398414616029 

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Name: yd Ind

EPSG: Indian yard

Type: length unit

Notes: Indian Foot = 0.99999566 British feet (A R Clarke 1865); British Yard (= 3 British feet), taken to be J S Clark’s 1865 value of 0.9144025 metres

Ref: G Bomford “The Re-adjustment of the Indian Triangulation”; Survey of India Professional Paper 28; 1939

Source: EPSG

Unit: metre

Multiplication factor: 0.914398530744441 

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Name: GLM

EPSG: German legal metre

Type: length unit

Notes: used in Namibia

Ref: Chief Directorate Surveys and Land Information; Mowbray; South Africa

Source: EPSG

Unit: metre

Multiplication factor: 1.0000135965 

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Name: ft (Sear)

EPSG: British foot (Sears 1922)

Type: length unit

Notes: uses Sears’ 1922 British yard-metre ratio as given by Bomford as 39.370147 inches per metre; used in East Malaysian and older New Zealand mapping

Ref: G Bomford “Geodesy” 2nd edition 1962; after J S Clark “Remeasurement of the Old Length Standards”; Empire Survey Review, no. 90

Source: EPSG

Unit: metre

Multiplication factor: 0.304799471538676 

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Name: ch (US)

EPSG: US Survey chain

Type: length unit

Notes: used in USA primarily for public lands cadastral work

Ref: Bureau of Land Management technical bulletin 6 (1973) and Standard Field Tables 8th Edition (1956)

Source: EPSG

Unit: metre

Multiplication factor: 20.1168402336805 

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Name: lk (US)

EPSG: US Survey link

Type: length unit

Notes: used in USA primarily for public lands cadastral work

Ref: Bureau of Land Management technical bulletin 6 (1973) and Standard Field Tables 8th Edition (1956)

Source: EPSG

Unit: metre

Multiplication factor: 20.1168402336805 

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Name: mile (US)

EPSG: US Survey mile

Type: length unit

Notes: used in USA primarily for public lands cadastral work

Ref: Bureau of Land Management technical bulletin 6 (1973) and Standard Field Tables 8th Edition (1956)

Source: EPSG

Unit: metre

Multiplication factor: 1609.34721869444 

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Name: degrees

EPSG: degree

Type: angular unit

Notes:p/180

Source: EPSG

Unit: radian

Multiplication factor: 1.74532925199533E-02 

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Name: radians

EPSG: radian

Type: angular unit

Notes: SI standard unit

Ref: ISO 1000

Source: EPSG

Unit: radian

Multiplication factor: 1 

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Name: DMS

EPSG: degree minute second

Type: angular unit

Notes: degrees<space>arcminutes<space>arcseconds

          degrees - integer
          arcminutes - integer
          arcseconds - real

Source: EPSG

Unit: radian 

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Name: gradians

EPSG: grad

Type: angular unit

Notes:p/180 - in France also abbreviated as "gr"

Source: EPSG

Unit: radian

Multiplication factor: 0.0157079633267949 

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Name: DM

EPSG: degrees decimal minutes

Type: angular unit

Notes: degrees<space>decimal minutes

          degrees - integer
          decimal minutes - integer

Source: EPSG

Unit: radian 

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Name: Tubo

EPSG: tubo

Type: real unit

Notes: 3 feet x 6 feet

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Note: The European Petroleum Survey Group (EPSG) was formed in 1986. It disseminates information to improve oil industry survey practices and procedures. From this group, the geodesy working group maintains a relational database of geodesy parameters which is used in SIS. The European Petroleum Survey Group has compiled and distributes the various geodetic and cartographic coordinate system parameters. The coordinate systems in this database are listed in SIS.

SIS uses version 8.5 of the EPSG CRS database.

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