uom_code,unit_of_meas_name,unit_of_meas_type,target_uom_code,factor_b,factor_c,remarks,information_source,data_source,revision_date,change_id,deprecated
1024,bin,scale,9201,1,1,,OGP,OGP,2012/07/14,2011.106,0
1025,millimetre,length,9001,1,1000,,ISO 1000.,OGP,2013/05/29,2013.021,0
1026,metres per second,length,1026,1,1,Length rate.,OGP,OGP,2013/05/29,2013.021,0
1027,millimetres per year,length,1026,1,31556925445,"Year taken to be IUGS definition of 31556925.445 seconds; see UoM code 1029.",ISO 1000.,OGP,2013/09/02,2013.021 2013.042,0
1028,parts per billion,scale,9201,1,1000000000,"Billion is internationally ambiguous, in different languages being 1E+9 and 1E+12. One billion taken here to be 1E+9.",OGP,OGP,2013/05/29,2013.021,0
1029,year,time,1040,31556925.445,1,,"International Union of Geological Sciences (IUGS) and International Union of Pure and Applied Chemistry (IUPAC). Pure Appl. Chem., Vol. 83, No. 5, pp. 1159–1162, 2011.",OGP,2013/05/28,2013.021,0
1030,parts per billion per year,scale,1036,1,3.1556925445e+16,"Year taken to be IUGS definition of 31556925.445 seconds; see UoM code 1029. Billion
    is internationally ambiguous, in different languages being 1E+9 and 1E+12. One billion taken
    here to be 1E+9.",ISO 1000.,OGP,2013/12/13,2013.021 2013.042 2013.067,0
1031,milliarc-second,angle,9101,3.14159265358979,648000000,= ((pi/180) / 3600 / 1000) radians,,OGP,2013/05/29,2013.021,0
1032,milliarc-seconds per year,angle,1035,3.14159265358979,2.044888768836e+16,"= ((pi/180) / 3600 / 1000) radians per year. Year taken to be IUGS definition of 31556925.445 seconds; see UoM code 1029.",,OGP,2013/09/02,2013.021 2013.042,0
1033,centimetre,length,9001,1,100,,ISO 1000.,OGP,2013/05/29,2013.021,0
1034,centimetres per year,length,1026,1,3155692544.5,"Year taken to be IUGS definition of 31556925.445 seconds; see UoM code 1029.",ISO 1000.,OGP,2013/09/02,2013.021 2013.042,0
1035,radians per second,angle,1035,1,1,Angle rate.,OGP,OGP,2013/05/29,2013.021,0
1036,unity per second,scale,1036,1,1,Scale rate.,OGP,OGP,2013/05/29,2013.021,0
1040,second,time,1040,1,1,Not to be confused with the angle unit arc-second.,ISO 1000.,OGP,2013/05/28,2013.021,0
1041,parts per million per year,scale,1036,1,31556925445000,"Year taken to be IUGS definition of 31556925.445 seconds; see UoM code 1029.",,OGP,2013/09/02,2013.021 2013.037 2013.042,0
1042,metres per year,length,1026,1,31556925.445,"Year taken to be IUGS definition of 31556925.445 seconds; see UoM code 1029.",OGP,OGP,2013/09/02,2013.021 2013.042,0
1043,arc-seconds per year,angle,1035,3.14159265358979,20448887688360,"=((pi/180) / 3600) radians per year. Year taken to be IUGS definition of 31556925.445 seconds; see UoM code 1029.",,OGP,2013/09/02,2013.021 2013.042,0
9001,metre,length,9001,1,1,Also known as International metre. SI standard unit.,ISO 1000.,OGP,1995/06/02,,0
9002,foot,length,9001,0.3048,1,,"ISO 1000; 1958",OGP,1995/06/02,,0
9003,US survey foot,length,9001,12,39.37,Used in USA.,OGP,OGP,2000/05/07,1999.990,0
9005,Clarke's foot,length,9001,0.3047972654,1,"Assumes Clarke's 1865 ratio of 1 British foot = 0.3047972654 French legal metres applies to the international metre.   Used in older Australian, southern African & British West Indian mapping.",Australian Land Information Group  www.auslig.gov.au,OGP,2005/09/06,1997.233 1999.990 2000.050 2005.370 2005.460,0
9014,fathom,length,9001,1.8288,1,= 6 feet.,,OGP,1995/06/02,,0
9030,nautical mile,length,9001,1852,1,,,OGP,1996/10/18,1996.240,0
9031,German legal metre,length,9001,1.0000135965,1,Used in Namibia.,"Chief Directorate Surveys and Land Information; Mowbray; South Africa",OGP,1997/06/16,,0
9033,US survey chain,length,9001,792,39.37,Used in USA primarily for public lands cadastral work.,Bureau of Land Management technical bulletin 6 (1973) and Standard Field Tables 8th edition (1956).,OGP,2000/05/07,1999.990,0
9034,US survey link,length,9001,7.92,39.37,Used in USA primarily for public lands cadastral work.,Bureau of Land Management technical bulletin 6 (1973) and Standard Field Tables 8th edition (1956).,OGP,2000/05/07,1999.990,0
9035,US survey mile,length,9001,63360,39.37,Used in USA primarily for public lands cadastral work.,Bureau of Land Management technical bulletin 6 (1973) and Standard Field Tables 8th edition (1956).,OGP,2000/05/07,1999.990,0
9036,kilometre,length,9001,1000,1,,ISO 1000.,OGP,1998/11/11,,0
9037,Clarke's yard,length,9001,0.9143917962,1,"=3 Clarke's feet.  Assumes Clarke's 1865 ratio of 1 British foot = 0.3047972654 French legal metres applies to the international metre.   Used in older Australian, southern African & British West Indian mapping.",Australian Land Information Group  www.auslig.gov.au,OGP,2005/09/06,1997.233 1999.990 2005.370 2005.460,0
9038,Clarke's chain,length,9001,20.1166195164,1,"=22 Clarke's yards.  Assumes Clarke's 1865 ratio of 1 British foot = 0.3047972654 French legal metres applies to the international metre.   Used in older Australian, southern African & British West Indian mapping.",Australian Land Information Group  www.auslig.gov.au,OGP,2005/09/06,1997.233 1999.990 2005.370 2005.460,0
9039,Clarke's link,length,9001,0.201166195164,1,"=1/100 Clarke's chain. Assumes Clarke's 1865 ratio of 1 British foot = 0.3047972654 French legal metres applies to the international metre.   Used in older Australian, southern African & British West Indian mapping.",Australian Land Information Group  www.auslig.gov.au,OGP,2005/09/06,1997.233 1999.990 2005.370 2005.460,0
9040,British yard (Sears 1922),length,9001,36,39.370147,Uses Sear's 1922 British yard-metre ratio as given by Bomford as 39.370147 inches per metre.  Used in East Malaysian and older New Zealand mapping.,"G. Bomford ""Geodesy"" 2nd edition 1962; after J.S.Clark ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2000/05/07,1997.233 1999.990,0
9041,British foot (Sears 1922),length,9001,12,39.370147,Uses Sear's 1922 British yard-metre ratio as given by Bomford as 39.370147 inches per metre.  Used in East Malaysian and older New Zealand mapping.,"G. Bomford ""Geodesy"" 2nd edition 1962; after J.S.Clark ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2000/05/07,1997.233 1999.990,0
9042,British chain (Sears 1922),length,9001,792,39.370147,Uses Sear's 1922 British yard-metre ratio as given by Bomford as 39.370147 inches per metre.  Used in East Malaysian and older New Zealand mapping.,"G. Bomford ""Geodesy"" 2nd edition 1962; after J.S.Clark ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2000/05/07,1997.233 1999.990,0
9043,British link (Sears 1922),length,9001,7.92,39.370147,Uses Sear's 1922 British yard-metre ratio as given by Bomford as 39.370147 inches per metre.  Used in East Malaysian and older New Zealand mapping.,"G. Bomford ""Geodesy"" 2nd edition 1962; after J.S.Clark ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2000/05/07,1997.233 1999.990,0
9050,British yard (Benoit 1895 A),length,9001,0.9143992,1,Uses Benoit's 1895 British yard-metre ratio as given by Clark as 0.9143992 metres per yard.  Used for deriving metric size of ellipsoid in Palestine.,"J.S.Clark; ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2006/03/21,1997.233 1999.990 2006.260,0
9051,British foot (Benoit 1895 A),length,9001,0.9143992,3,Uses Benoit's 1895 British yard-metre ratio as given by Clark as 0.9143992 metres per yard.  Used for deriving metric size of ellipsoid in Palestine.,"J.S.Clark; ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2006/03/21,1997.233 1999.990 2006.260,0
9052,British chain (Benoit 1895 A),length,9001,20.1167824,1,Uses Benoit's 1895 British yard-metre ratio as given by Clark as 0.9143992 metres per yard.  Used for deriving metric size of ellipsoid in Palestine.,"J.S.Clark; ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2006/03/21,1997.233 1999.990 2006.260,0
9053,British link (Benoit 1895 A),length,9001,0.201167824,1,Uses Benoit's 1895 British yard-metre ratio as given by Clark as 0.9143992 metres per yard.  Used for deriving metric size of ellipsoid in Palestine.,"J.S.Clark; ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2006/03/21,1997.233 1999.990 2006.260,0
9060,British yard (Benoit 1895 B),length,9001,36,39.370113,"G. Bomford ""Geodesy"" 2nd edition 1962; after J.S.Clark ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.","G. Bomford ""Geodesy"" 2nd edition 1962; after J.S.Clark ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2000/05/07,1997.233 1999.990,0
9061,British foot (Benoit 1895 B),length,9001,12,39.370113,Uses Benoit's 1895 British yard-metre ratio as given by Bomford as 39.370113 inches per metre.  Used in West Malaysian mapping.,"G. Bomford ""Geodesy"" 2nd edition 1962; after J.S.Clark ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2000/05/07,1997.233 1999.990,0
9062,British chain (Benoit 1895 B),length,9001,792,39.370113,Uses Benoit's 1895 British yard-metre ratio as given by Bomford as 39.370113 inches per metre.  Used in West Malaysian mapping.,"G. Bomford ""Geodesy"" 2nd edition 1962; after J.S.Clark ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2000/05/07,1997.233 1999.990,0
9063,British link (Benoit 1895 B),length,9001,7.92,39.370113,Uses Benoit's 1895 British yard-metre ratio as given by Bomford as 39.370113 inches per metre.  Used in West Malaysian mapping.,"G. Bomford; ""Geodesy""; 3rd edition 1975",OGP,2000/05/07,1997.233 1999.990,0
9070,British foot (1865),length,9001,0.9144025,3,Uses Clark's estimate of 1853-1865 British foot-metre ratio of 0.9144025 metres per yard.  Used in 1962 and 1975 estimates of Indian foot.,"J.S.Clark; ""Remeasurement of the Old Length Standards""; Empire Survey Review no. 90; 1953.",OGP,2000/05/07,1997.233 1999.990,0
9080,Indian foot,length,9001,12,39.370142,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.,"G. Bomford; ""The Re-adjustment of the Indian Triangulation""; Survey of India Professional Paper 28; 1939.",OGP,2000/05/07,1997.231 1999.990,0
9081,Indian foot (1937),length,9001,0.30479841,1,Indian Foot = 0.99999566 British feet (A.R.Clarke 1865).  British foot taken to be 1895 Benoit value of 12/39.370113m.  Rounded to 8 decimal places as 0.30479841. Used from Bangladesh to Vietnam.  Previously used in India and Pakistan but superseded.,"G. Bomford; ""The Re-adjustment of the Indian Triangulation""; Survey of India Professional Paper 28; 1939.",OGP,2000/05/07,1997.231 1999.990,0
9082,Indian foot (1962),length,9001,0.3047996,1,Indian Foot = 0.99999566 British feet (A.R.Clarke 1865).  British yard (3 feet) taken to be J.S. Clark's 1865 value of 0.9144025m. Rounded to 7 significant figures with a small error as 1 Ind ft=0.3047996m.  Used in Pakistan since metrication.,"G. Bomford; ""Geodesy""; 2nd edition 1962",OGP,2007/01/25,1997.231 1999.990 2007.011,0
9083,Indian foot (1975),length,9001,0.3047995,1,Indian Foot = 0.99999566 British feet (A.R.Clarke 1865).  British yard (3 feet) taken to be J.S. Clark's 1865 value of 0.9144025m. Rounded to 7 significant figures as 1 Ind ft=0.3047995m.  Used in India since metrication.,"G. Bomford; ""Geodesy""; 3rd edition 1975",OGP,2007/01/25,1997.231 1999.990 2007.011,0
9084,Indian yard,length,9001,36,39.370142,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.,"G. Bomford; ""The Re-adjustment of the Indian Triangulation""; Survey of India Professional Paper 28; 1939.",OGP,2000/05/07,1997.231 1999.990,0
9085,Indian yard (1937),length,9001,0.91439523,1,Indian Foot = 0.99999566 British feet (A.R.Clarke 1865).  British foot taken to be 1895 Benoit value of 12/39.370113m.  Rounded to 8 decimal places as 0.30479841. Used from Bangladesh to Vietnam.  Previously used in India and Pakistan but superseded.,"G. Bomford; ""The Re-adjustment of the Indian Triangulation""; Survey of India Professional Paper 28; 1939.",OGP,2000/05/07,1997.231 1999.990,0
9086,Indian yard (1962),length,9001,0.9143988,1,Indian Foot = 0.99999566 British feet (A.R.Clarke 1865).  British yard (3 feet) taken to be J.S. Clark's 1865 value of 0.9144025m. Rounded to 7 significant figures with a small error as 1 Ind ft=0.3047996m.  Used in Pakistan since metrication.,"G. Bomford; ""Geodesy""; 2nd edition 1962",OGP,2007/01/25,1997.231 1999.990 2007.011,0
9087,Indian yard (1975),length,9001,0.9143985,1,Indian Foot = 0.99999566 British feet (A.R.Clarke 1865).  British yard (3 feet) taken to be J.S. Clark's 1865 value of 0.9144025m. Rounded to 7 significant figures as 1 Ind ft=0.3047995m.  Used in India since metrication.,"G. Bomford; ""Geodesy""; 3rd edition 1975",OGP,2007/01/25,1997.231 1999.990 2007.011,0
9093,Statute mile,length,9001,1609.344,1,=5280 feet,OGP,OGP,2000/03/07,,0
9094,Gold Coast foot,length,9001,6378300,20926201,"Used in Ghana and some adjacent parts of British west Africa prior to metrication, except for the metrication of projection defining parameters when British foot (Sears 1922) used.",Ordnance Survey International,OGP,2001/01/21,2000.861,0
9095,British foot (1936),length,9001,0.3048007491,1,For the 1936 retriangulation OSGB defines the relationship of 10 feet of 1796 to the International metre through the logarithmic relationship (10^0.48401603 exactly). 1 ft = 0.3048007491…m. Also used for metric conversions in Ireland.,"1. ""The Retriangulation of Great Britain"", Ordnance Survey of Great Britain.
2. ""The Irish Grid - A Description of the Co-ordinate Reference System"" published by Ordnance Survey of Ireland, Dublin and Ordnance Survey of Northern Ireland, Belfast.",OGP,2006/11/27,2002.621 2006.932,0
9096,yard,length,9001,0.9144,1,=3 international feet.,OGP,OGP,2006/07/14,,0
9097,chain,length,9001,20.1168,1,=22 international yards or 66 international feet.,OGP,OGP,2006/07/14,,0
9098,link,length,9001,20.1168,100,=1/100 international chain.,OGP,OGP,2006/07/14,,0
9099,British yard (Sears 1922 truncated),length,9001,0.914398,1,Uses Sear's 1922 British yard-metre ratio (UoM code 9040) truncated to 6 significant figures.,Defence Geographic Centre,OGP,2006/10/23,2006.901,0
9101,radian,angle,9101,1,1,SI standard unit.,ISO 1000:1992,OGP,1995/06/02,,0
9102,degree,angle,9101,3.14159265358979,180,= pi/180 radians,,OGP,2002/11/18,1996.220 2002.860,0
9103,arc-minute,angle,9101,3.14159265358979,10800,1/60th degree = ((pi/180) / 60) radians,,OGP,2002/11/18,1996.220 2002.860,0
9104,arc-second,angle,9101,3.14159265358979,648000,1/60th arc-minute = ((pi/180) / 3600) radians,,OGP,2002/11/18,1996.220 2002.860,0
9105,grad,angle,9101,3.14159265358979,200,=pi/200 radians.,,OGP,2002/11/18,1996.220 1999.050 2002.860,0
9106,gon,angle,9101,3.14159265358979,200,=pi/200 radians,,OGP,2002/11/18,1996.220 2002.860,0
9107,degree minute second,angle,9102,,,"Degree representation. Format: signed degrees (integer) - arc-minutes (integer) - arc-seconds (real, any precision). Different symbol sets are in use as field separators, for example º ' "". Convert to degrees using algorithm.",OGP,OGP,2002/11/22,1996.190 2002.070 2002.780,0
9108,degree minute second hemisphere,angle,9102,,,"Degree representation. Format: degrees (integer) - arc-minutes (integer) - arc-seconds (real) - hemisphere abbreviation (single character N S E or W). Different symbol sets are in use as field separators for example º ' "". Convert to deg using algorithm.",OGP,OGP,2002/11/22,1996.190 2002.070 2002.780,0
9109,microradian,angle,9101,1,1000000,rad * 10E-6,ISO 1000.,OGP,1996/10/18,1999.050,0
9110,sexagesimal DMS,angle,9102,,,Pseudo unit. Format: signed degrees - period - minutes (2 digits) - integer seconds (2 digits) - fraction of seconds (any precision). Must include leading zero in minutes and seconds and exclude decimal point for seconds. Convert to degree using formula.,OGP,OGP,2008/03/26,2002.270 2002.780 2008.020,0
9111,sexagesimal DM,angle,9102,,,Pseudo unit. Format: sign - degrees - decimal point - integer minutes (two digits) - fraction of minutes (any precision).  Must include leading zero in integer minutes.  Must exclude decimal point for minutes.  Convert to deg using algorithm.,OGP,OGP,2002/11/22,2002.070 2002.780,0
9112,centesimal minute,angle,9101,3.14159265358979,20000,1/100 of a grad and gon = ((pi/200) / 100) radians,http://www.geodesy.matav.hu/,OGP,2005/09/06,1998.480 1999.510 2002.860 2005.460,0
9113,centesimal second,angle,9101,3.14159265358979,2000000,"1/100 of a centesimal minute or 1/10,000th of a grad and gon = ((pi/200) / 10000) radians",http://www.geodesy.matav.hu/,OGP,2005/09/06,1999.510 2002.860 2005.460,0
9114,mil_6400,angle,9101,3.14159265358979,3200,Angle subtended by 1/6400 part of a circle.  Approximates to 1/1000th radian.  Note that other approximations (notably 1/6300 circle and 1/6000 circle) also exist.,http://www.geodesy.matav.hu/,OGP,2005/09/06,1999.510 2005.460,0
9115,degree minute,angle,9102,,,"Degree representation. Format: signed degrees (integer)  - arc-minutes (real, any precision). Different symbol sets are in use as field separators, for example º '. Convert to degrees using algorithm.",OGP,OGP,2002/11/22,2002.780,0
9116,degree hemisphere,angle,9102,,,"Degree representation. Format: degrees (real, any precision) - hemisphere abbreviation (single character N S E or W). Convert to degrees using algorithm.",OGP,OGP,2002/11/22,,0
9117,hemisphere degree,angle,9102,,,"Degree representation. Format: hemisphere abbreviation (single character N S E or W) - degrees (real, any precision). Convert to degrees using algorithm.",OGP,OGP,2002/11/22,,0
9118,degree minute hemisphere,angle,9102,,,"Degree representation. Format: degrees (integer) - arc-minutes (real, any precision) - hemisphere abbreviation (single character N S E or W). Different symbol sets are in use as field separators, for example º '. Convert to degrees using algorithm.",OGP,OGP,2002/11/22,,0
9119,hemisphere degree minute,angle,9102,,,"Degree representation. Format:  hemisphere abbreviation (single character N S E or W) - degrees (integer) - arc-minutes (real, any precision). Different symbol sets are in use as field separators, for example º '. Convert to degrees using algorithm.",OGP,OGP,2002/11/22,,0
9120,hemisphere degree minute second,angle,9102,,,"Degree representation. Format: hemisphere abbreviation (single character N S E or W) - degrees (integer) - arc-minutes (integer) - arc-seconds (real). Different symbol sets are in use as field separators for example º ' "". Convert to deg using algorithm.",OGP,OGP,2002/11/22,,0
9121,sexagesimal DMS.s,angle,9102,,,"Pseudo unit. Format: signed degrees - minutes (two digits) - seconds (real, any precision). Must include leading zero in minutes and seconds where value is under 10 and include decimal separator for seconds. Convert to degree using algorithm.",ISO 6709:1983.,OGP,2002/11/22,,0
9122,degree (supplier to define representation),angle,9101,3.14159265358979,180,"= pi/180 radians. The degree representation (e.g. decimal, DMSH, etc.) must be clarified by suppliers of data associated with this code.",OGP,OGP,2004/01/05,,0
9201,unity,scale,9201,1,1,,,OGP,1996/09/12,,0
9202,parts per million,scale,9201,1,1000000,,,OGP,2013/07/26,2013.021 2013.037,0
9203,coefficient,scale,9201,1,1,Used when parameters are coefficients.  They inherently take the units which depend upon the term to which the coefficient applies.,OGP,OGP,2004/09/14,2004.530,0
9204,Bin width 330 US survey feet,length,9001,3960,39.37,,OGP,OGP,2000/10/19,2000.590 2011.106,1
9205,Bin width 165 US survey feet,length,9001,1980,39.37,,OGP,OGP,2000/10/19,2000.590 2011.106,1
9206,Bin width 82.5 US survey feet,length,9001,990,39.37,,OGP,OGP,2000/10/19,2000.590 2011.106,1
9207,Bin width 37.5 metres,length,9001,37.5,1,,OGP,OGP,2000/10/19,2000.590 2011.106,1
9208,Bin width 25 metres,length,9001,25,1,,OGP,OGP,2000/10/19,2000.590 2011.106,1
9209,Bin width 12.5 metres,length,9001,12.5,1,,OGP,OGP,2000/10/19,2000.590 2011.106,1
9210,Bin width 6.25 metres,length,9001,6.25,1,,OGP,OGP,2000/10/19,2000.590 2011.106,1
9211,Bin width 3.125 metres,length,9001,3.125,1,,OGP,OGP,2000/10/19,2000.590 2011.106,1
9300,British foot (Sears 1922 truncated),length,9001,0.914398,3,"Uses Sear's 1922 British yard-metre ratio (UoM code 9040) truncated to 6 significant figures; this truncated ratio (0.914398, UoM code 9099) then converted to other imperial units. 3 ftSe(T) = 1 ydSe(T).",Defence Geographic Centre,OGP,2006/10/23,2006.901,0
9301,British chain (Sears 1922 truncated),length,9001,20.116756,1,"Uses Sear's 1922 British yard-metre ratio (UoM code 9040) truncated to 6 significant figures; this truncated ratio (0.914398, UoM code 9099) then converted to other imperial units. 1 chSe(T) = 22 ydSe(T). Used in metrication of Malaya RSO grid.",Defence Geographic Centre,OGP,2006/10/23,2006.901,0
9302,British link (Sears 1922 truncated),length,9001,20.116756,100,"Uses Sear's 1922 British yard-metre ratio (UoM code 9040) truncated to 6 significant figures; this truncated ratio (0.914398, UoM code 9099) then converted to other imperial units. 100 lkSe(T) = 1 chSe(T).",Defence Geographic Centre,OGP,2006/10/23,2006.901,0
