diff --git a/src/si_ref_point/aboxes/constants_abox.py b/src/si_ref_point/aboxes/constants_abox.py
index b696615..62aabc7 100644
--- a/src/si_ref_point/aboxes/constants_abox.py
+++ b/src/si_ref_point/aboxes/constants_abox.py
@@ -3,6 +3,7 @@
 from datetime import datetime, timezone
 import git
 import os
+from decimal import Decimal
 from rdflib import Graph, URIRef, RDF, OWL, SKOS, XSD, RDFS, DCTERMS, Literal, PROV
 import yaml
 
@@ -180,7 +181,7 @@ def main():
                                      si_graph.has_unit,
                                      si_graph.set_unit_uri(cst['unit'])))
         constants_graph.add((element, si_graph.has_value,
-                             Literal(cst['value'], datatype=XSD[cst['xsd_type']], normalize=False)))
+                             Literal(str(format(Decimal(cst['value']), 'f')), datatype=XSD[cst['xsd_type']], normalize=False)))
         constants_graph.add((element, si_graph.has_datatype, XSD[cst['xsd_type']]))
         # note on xsd:double :
         # RDFLib has a known bug that loses precision in value for xsd:double
diff --git a/src/si_ref_point/aboxes/prefixes_abox.py b/src/si_ref_point/aboxes/prefixes_abox.py
index c6e3269..69a9656 100644
--- a/src/si_ref_point/aboxes/prefixes_abox.py
+++ b/src/si_ref_point/aboxes/prefixes_abox.py
@@ -5,6 +5,7 @@
 import git
 import os
 import yaml
+from decimal import Decimal
 from rdflib import Graph, URIRef, RDF, OWL, SKOS, XSD, RDFS, DCTERMS, Literal, PROV
 from si_ref_point.tboxes.si_tbox import SiElements
 from si_ref_point.settings import PKG_ROOT, CC_LICENCE, CC_LICENCE_TEXT_EN, CC_LICENCE_TEXT_FR, SI_FILES_FOLDER, GITHUB_BASE_PATH
@@ -155,7 +156,7 @@ def main():
         uri_text = prfx['URI']
         pref_label_en = prfx['prefLabel_en']
         pref_label_fr = prfx['prefLabel_fr']
-        scaling_factor = prfx['ScalingFactor']
+        scaling_factor = format(Decimal(prfx['ScalingFactor']), 'f')
         exponent = prfx['Exponent']
         symbol = prfx['hasSymbol']
         defres = prfx['hasDefiningResolution']
@@ -168,7 +169,7 @@ def main():
             prefix_graph.add((element, SKOS.prefLabel, Literal(pref_label_fr, lang='fr')))
             prefix_graph.add((element, SKOS.prefLabel, Literal(pref_label_en, lang='en')))
             prefix_graph.add((element, si_graph.has_scaling_factor,
-                Literal(scaling_factor, datatype=XSD[xsd_type], normalize=False)))
+                Literal(str(scaling_factor), datatype=XSD[xsd_type], normalize=False)))
             prefix_graph.add((element, si_graph.has_datatype, XSD[xsd_type]))
             prefix_graph.add(
                 (
diff --git a/src/si_ref_point/aboxes/units_abox.py b/src/si_ref_point/aboxes/units_abox.py
index cd1ada6..2dce6bb 100644
--- a/src/si_ref_point/aboxes/units_abox.py
+++ b/src/si_ref_point/aboxes/units_abox.py
@@ -7,6 +7,7 @@
 import os
 import logging
 import yaml
+from decimal import Decimal
 from rdflib import Graph, URIRef, BNode, Literal, RDF, OWL, SKOS, XSD, RDFS, DCTERMS, PROV
 from si_ref_point.tboxes.si_tbox import SiElements
 import si_ref_point.aboxes.symbols_format as sf
@@ -704,13 +705,13 @@ def main():
 
                 if isinstance(nsi["ConversionFactor"], int):
                     conv_factor_type = XSD.integer
-                elif isinstance(nsi["ConversionFactor"], float):
-                    conv_factor_type = XSD.float
+                elif isinstance(nsi["ConversionFactor"], str):
+                    conv_factor_type = XSD.decimal
                 else:
                     logging.error('Error : unknown ConversionFactor type : %s ',
                                   nsi["ConversionFactor"])
                     conv_factor_type = None
-                conversion_factor = Literal(nsi["ConversionFactor"],
+                conversion_factor = Literal(str(format(Decimal(nsi["ConversionFactor"]), 'f')),
                                            datatype=conv_factor_type)
                 conversion_factor_as_string = Literal(
                     nsi["ConversionFactorAsString"],
diff --git a/src/si_ref_point/inputs/si/base_units_defs.yaml b/src/si_ref_point/inputs/si/base_units_defs.yaml
index a0f335e..f749a75 100644
--- a/src/si_ref_point/inputs/si/base_units_defs.yaml
+++ b/src/si_ref_point/inputs/si/base_units_defs.yaml
@@ -3,7 +3,7 @@ meta:
   wasAssociatedWith: "Frédéric Meynadier"
   wasGeneratedBy: "manual YAML generation"
   startedAtTime: "2023-01-01"
-  wasDerivedFrom: "SI Brochure 9th ed, V3.01"  
+  wasDerivedFrom: "SI Brochure 9th ed, V3.02"  
 data:
 - URI: ampere1948
   prefLabel_fr: ampère1948
diff --git a/src/si_ref_point/inputs/si/def_collectors.yaml b/src/si_ref_point/inputs/si/def_collectors.yaml
index 7e99bb9..9ea3064 100644
--- a/src/si_ref_point/inputs/si/def_collectors.yaml
+++ b/src/si_ref_point/inputs/si/def_collectors.yaml
@@ -4,7 +4,7 @@ meta:
   wasAssociatedWith: "Frédéric Meynadier"
   wasGeneratedBy: "manual YAML generation"
   startedAtTime: "2023-01-01"
-  wasDerivedFrom: "SI Brochure 9th ed, V3.01"
+  wasDerivedFrom: "SI Brochure 9th ed, V3.02"
 data:
 - URI: ampere
   prefLabel(fr): ampère
diff --git a/src/si_ref_point/inputs/si/non_si_units.yaml b/src/si_ref_point/inputs/si/non_si_units.yaml
index 88bb73a..3190c43 100644
--- a/src/si_ref_point/inputs/si/non_si_units.yaml
+++ b/src/si_ref_point/inputs/si/non_si_units.yaml
@@ -3,7 +3,7 @@ meta:
   wasAssociatedWith: "Frédéric Meynadier"
   wasGeneratedBy: "manual YAML generation"
   startedAtTime: "2023-01-01"
-  wasDerivedFrom: "SI Brochure 9th ed, V3.01"  
+  wasDerivedFrom: "SI Brochure 9th ed, V3.02"  
 data:
 - URI: minute
   prefLabel_fr: minute
@@ -46,7 +46,7 @@ data:
   prefLabel_en: degree
   Symbol: °
   UnitOfQtyKind: ANGP
-  ConversionFactor: 0.0174532925199433
+  ConversionFactor: "0.017453292519943295769236907684886"
   ConversionFactorAsString: "(π \\; / \\; 180)"
   ConversionUnit: radian
   PrefixRestriction: true
@@ -55,7 +55,7 @@ data:
   prefLabel_en: arcminute
   Symbol: ′
   UnitOfQtyKind: ANGP
-  ConversionFactor: 0.000290888208665722
+  ConversionFactor: "0.00029088820866572159615394846141476"
   ConversionFactorAsString: "(π \\; / \\; 10800)"
   ConversionUnit: radian
   PrefixRestriction: true
@@ -64,7 +64,7 @@ data:
   prefLabel_en: arcsecond
   Symbol: ″
   UnitOfQtyKind: ANGP
-  ConversionFactor: 4.84813681109536e-06
+  ConversionFactor: "4.8481368110953599358991410235794e-6"
   ConversionFactorAsString: "(π \\; / \\; 648000)"
   ConversionUnit: radian
   PrefixRestriction: true
@@ -74,7 +74,7 @@ data:
   Symbol: L
   AltSymbol: l
   UnitOfQtyKind: VOLU
-  ConversionFactor: 0.001
+  ConversionFactor: "0.001"
   ConversionFactorAsString: "0.001"
   ConversionUnit:
     - [metre, "3"]
@@ -92,15 +92,15 @@ data:
   prefLabel_en: dalton
   Symbol: Da
   UnitOfQtyKind: MASS
-  ConversionFactor: 1.66053906660e-27
-  ConversionFactorAsString: "1.660\\:539\\:066\\:60(50) \\times 10^{-27}"
+  ConversionFactor: "1.66053906892e-27"
+  ConversionFactorAsString: "1.660\\:539\\:068\\:92(52) \\times 10^{-27}"
   ConversionUnit: kilogram
 - URI: electronvolt
   prefLabel_fr: électronvolt
   prefLabel_en: electronvolt
   Symbol: eV
   UnitOfQtyKind: ENGY
-  ConversionFactor: 1.602176634e-19
+  ConversionFactor: "1.602176634e-19"
   ConversionFactorAsString: "1.602\\:176\\:634 \\times 10^{-19}"
   ConversionUnit: joule
 - URI: neper
diff --git a/src/si_ref_point/inputs/si/notes.yaml b/src/si_ref_point/inputs/si/notes.yaml
index d015998..d196222 100644
--- a/src/si_ref_point/inputs/si/notes.yaml
+++ b/src/si_ref_point/inputs/si/notes.yaml
@@ -3,7 +3,7 @@ meta:
   wasAssociatedWith: "Frédéric Meynadier"
   wasGeneratedBy: "manual YAML generation"
   startedAtTime: "2023-01-01"
-  wasDerivedFrom: "SI Brochure 9th ed, V3.01"
+  wasDerivedFrom: "SI Brochure 9th ed, V3.02"
 data:
 - dbid: 1
   uri: second2018
diff --git a/src/si_ref_point/inputs/si/prefixes.yaml b/src/si_ref_point/inputs/si/prefixes.yaml
index 764c088..676e163 100644
--- a/src/si_ref_point/inputs/si/prefixes.yaml
+++ b/src/si_ref_point/inputs/si/prefixes.yaml
@@ -3,57 +3,57 @@ meta:
   wasAssociatedWith: "Frédéric Meynadier"
   wasGeneratedBy: "manual YAML generation"
   startedAtTime: "2023-01-01"
-  wasDerivedFrom: "SI Brochure 9th ed, V3.01"
+  wasDerivedFrom: "SI Brochure 9th ed, V3.02"
 data:
 - URI: quetta
   prefLabel_en: quetta
   prefLabel_fr: quetta
-  ScalingFactor: 1e+30
+  ScalingFactor: 1e30
   Exponent: +30
   hasSymbol: Q
   hasDefiningResolution: CGPM27-Res3
-  xsd_type: float
+  xsd_type: integer
   Comments:
 - URI: ronna
   prefLabel_en: ronna
   prefLabel_fr: ronna
-  ScalingFactor: 1e+27
+  ScalingFactor: 1e27
   Exponent: +27
   hasSymbol: R
   hasDefiningResolution: CGPM27-Res3
-  xsd_type: float
+  xsd_type: integer
   Comments:
 - URI: yotta
   prefLabel_en: yotta
   prefLabel_fr: yotta
-  ScalingFactor: 1e+24
+  ScalingFactor: 1e24
   Exponent: +24
   hasSymbol: Y
   hasDefiningResolution: CGPM19-Res4
-  xsd_type: float
+  xsd_type: integer
   Comments:
 - URI: zetta
   prefLabel_en: zetta
   prefLabel_fr: zetta
-  ScalingFactor: 1e+21
+  ScalingFactor: 1e21
   Exponent: +21
   hasSymbol: Z
   hasDefiningResolution: CGPM19-Res4
-  xsd_type: float
+  xsd_type: integer
   Comments:
 - URI: exa
   prefLabel_en: exa
   prefLabel_fr: exa
-  ScalingFactor: 1e+18
+  ScalingFactor: 1e18
   Exponent: +18
   hasSymbol: E
   hasDefiningResolution: CGPM15-Res10
-  xsd_type: float
+  xsd_type: integer
   Comments:
 - URI: peta
   prefLabel_en: peta
   prefLabel_fr: péta
-  ScalingFactor: 1000000000000000
+  ScalingFactor: 1e15
   Exponent: +15
   hasSymbol: P
   hasDefiningResolution: CGPM15-Res10
@@ -62,7 +62,7 @@ data:
 - URI: tera
   prefLabel_en: tera
   prefLabel_fr: téra
-  ScalingFactor: 1000000000000
+  ScalingFactor: 1e12
   Exponent: +12
   hasSymbol: T
   hasDefiningResolution: CGPM11-Res12
@@ -71,7 +71,7 @@ data:
 - URI: giga
   prefLabel_en: giga
   prefLabel_fr: giga
-  ScalingFactor: 1000000000
+  ScalingFactor: 1e9
   Exponent: +9
   hasSymbol: G
   hasDefiningResolution: CGPM11-Res12
@@ -80,7 +80,7 @@ data:
 - URI: mega
   prefLabel_en: mega
   prefLabel_fr: méga
-  ScalingFactor: 1000000
+  ScalingFactor: 1e6
   Exponent: +6
   hasSymbol: M
   hasDefiningResolution: CGPM11-Res12
@@ -89,7 +89,7 @@ data:
 - URI: kilo
   prefLabel_en: kilo
   prefLabel_fr: kilo
-  ScalingFactor: 1000
+  ScalingFactor: 1e3
   Exponent: +3
   hasSymbol: k
   hasDefiningResolution: CGPM11-Res12
@@ -98,7 +98,7 @@ data:
 - URI: hecto
   prefLabel_en: hecto
   prefLabel_fr: hecto
-  ScalingFactor: 100
+  ScalingFactor: 1e2
   Exponent: +2
   hasSymbol: h
   hasDefiningResolution: CGPM11-Res12
@@ -107,7 +107,7 @@ data:
 - URI: deca
   prefLabel_en: deca
   prefLabel_fr: déca
-  ScalingFactor: 10
+  ScalingFactor: 1e1
   Exponent: +1
   hasSymbol: da
   hasDefiningResolution: CGPM11-Res12
@@ -116,7 +116,7 @@ data:
 - URI: deci
   prefLabel_en: deci
   prefLabel_fr: déci
-  ScalingFactor: 0.1
+  ScalingFactor: 1e-1
   Exponent: -1
   hasSymbol: d
   hasDefiningResolution: CGPM11-Res12
@@ -125,7 +125,7 @@ data:
 - URI: centi
   prefLabel_en: centi
   prefLabel_fr: centi
-  ScalingFactor: 0.01
+  ScalingFactor: 1e-2
   Exponent: -2
   hasSymbol: c
   hasDefiningResolution: CGPM11-Res12
@@ -134,7 +134,7 @@ data:
 - URI: milli
   prefLabel_en: milli
   prefLabel_fr: milli
-  ScalingFactor: 0.001
+  ScalingFactor: 1e-3
   Exponent: -3
   hasSymbol: m
   hasDefiningResolution: CGPM11-Res12
@@ -147,7 +147,7 @@ data:
   Exponent: -6
   hasSymbol: µ
   hasDefiningResolution: CGPM11-Res12
-  xsd_type: float
+  xsd_type: decimal
   Comments: Tried with latex - fine without bold, but more difficult with.  Would
     require two symbols one bolded the other not.
 - URI: nano
@@ -157,7 +157,7 @@ data:
   Exponent: -9
   hasSymbol: n
   hasDefiningResolution: CGPM11-Res12
-  xsd_type: float
+  xsd_type: decimal
   Comments:
 - URI: pico
   prefLabel_en: pico
@@ -166,7 +166,7 @@ data:
   Exponent: -12
   hasSymbol: p
   hasDefiningResolution: CGPM11-Res12
-  xsd_type: float
+  xsd_type: decimal
   Comments:
 - URI: femto
   prefLabel_en: femto
@@ -175,7 +175,7 @@ data:
   Exponent: -15
   hasSymbol: f
   hasDefiningResolution: CGPM12-Res8
-  xsd_type: float
+  xsd_type: decimal
   Comments:
 - URI: atto
   prefLabel_en: atto
@@ -184,7 +184,7 @@ data:
   Exponent: -18
   hasSymbol: a
   hasDefiningResolution: CGPM12-Res8
-  xsd_type: float
+  xsd_type: decimal
   Comments:
 - URI: zepto
   prefLabel_en: zepto
@@ -193,7 +193,7 @@ data:
   Exponent: -21
   hasSymbol: z
   hasDefiningResolution: CGPM19-Res4
-  xsd_type: float
+  xsd_type: decimal
   Comments:
 - URI: yocto
   prefLabel_en: yocto
@@ -202,7 +202,7 @@ data:
   Exponent: -24
   hasSymbol: y
   hasDefiningResolution: CGPM19-Res4
-  xsd_type: float
+  xsd_type: decimal
   Comments:
 - URI: ronto
   prefLabel_en: ronto
@@ -211,7 +211,7 @@ data:
   Exponent: -27
   hasSymbol: r
   hasDefiningResolution: CGPM27-Res3
-  xsd_type: float
+  xsd_type: decimal
   Comments:
 - URI: quecto
   prefLabel_en: quecto
@@ -220,7 +220,7 @@ data:
   Exponent: -30
   hasSymbol: q
   hasDefiningResolution: CGPM27-Res3
-  xsd_type: float
+  xsd_type: decimal
   Comments:
 - URI: none
   prefLabel_en: none
@@ -229,5 +229,5 @@ data:
   Exponent: 0
   hasSymbol: 
   hasDefiningResolution: 
-  xsd_type: float
+  xsd_type: decimal
   Comments: "not an official prefix"
diff --git a/src/si_ref_point/inputs/si/si_constants.yaml b/src/si_ref_point/inputs/si/si_constants.yaml
index edf6ae2..e7e5a30 100644
--- a/src/si_ref_point/inputs/si/si_constants.yaml
+++ b/src/si_ref_point/inputs/si/si_constants.yaml
@@ -3,7 +3,7 @@ meta:
   wasAssociatedWith: "Frédéric Meynadier"
   wasGeneratedBy: "manual YAML generation"
   startedAtTime: "2023-01-01"
-  wasDerivedFrom: "SI Brochure 9th ed, V3.01"
+  wasDerivedFrom: "SI Brochure 9th ed, V3.02"
 data:
 - id: HyperfineTransitionFrequencyOfCs-133
   hidden_label: HyperfineSplitting
@@ -11,7 +11,7 @@ data:
   name_fr: fréquence de la transition hyperfine du césium
   xsd_type: integer
   value_str: 9 192 631 770
-  value: 9192631770
+  value: "9192631770"
   unit: hertz
   symbol: '@hfcs@'
   updateddate: '1967-10-13'
@@ -23,7 +23,7 @@ data:
   name_fr: vitesse de la lumière dans le vide
   xsd_type: integer
   value_str: 299 792 458
-  value: 299792458
+  value: "299792458"
   unit:
     - [metre, "1"]
     - [second, "-1"]
@@ -35,9 +35,9 @@ data:
   hidden_label: Planck
   name_en: Planck constant
   name_fr: constante de Planck
-  xsd_type: float
+  xsd_type: decimal
   value_str: 6.626 070 15 x 10⁻³⁴
-  value: 6.62607015e-34
+  value: "6.62607015e-34"
   unit:
     - [joule, "1"]
     - [second, "1"]
@@ -49,9 +49,9 @@ data:
   hidden_label: ElementaryCharge
   name_en: elementary charge
   name_fr: charge élementaire
-  xsd_type: float
+  xsd_type: decimal
   value_str: 1.602 176 634 x 10⁻¹⁹
-  value: 1.602176634e-19
+  value: "1.602176634e-19"
   unit: coulomb
   symbol: '@elms@'
   updateddate: '2019-05-20'
@@ -61,9 +61,9 @@ data:
   hidden_label: Boltzmann
   name_en: Boltzmann constant
   name_fr: constante de Boltzmann
-  xsd_type: float
+  xsd_type: decimal
   value_str: 1.380 649 x 10⁻²³
-  value: 1.380649e-23
+  value: "1.380649e-23"
   unit:
     - [joule, "1"]
     - [kelvin, "-1"]
@@ -75,9 +75,9 @@ data:
   hidden_label: Avogadro
   name_en: Avogadro constant
   name_fr: constante d'Avogadro
-  xsd_type: float
+  xsd_type: integer
   value_str: 6.022 140 76 x 10²³
-  value: 6.02214076e+23
+  value: "6.02214076e+23"
   unit:
     - [mole, "-1"]
   symbol: '@avos@'
@@ -90,7 +90,7 @@ data:
   name_fr: efficacité lumineuse
   xsd_type: integer
   value_str: '683'
-  value: 683
+  value: "683"
   unit:
     - [lumen, "1"]
     - [watt, "-1"]
diff --git a/src/si_ref_point/inputs/si/si_units_special_names.yaml b/src/si_ref_point/inputs/si/si_units_special_names.yaml
index 2a0cf9f..0d74511 100644
--- a/src/si_ref_point/inputs/si/si_units_special_names.yaml
+++ b/src/si_ref_point/inputs/si/si_units_special_names.yaml
@@ -3,7 +3,7 @@ meta:
   wasAssociatedWith: "Frédéric Meynadier"
   wasGeneratedBy: "manual YAML generation"
   startedAtTime: "2023-01-01"
-  wasDerivedFrom: "SI Brochure 9th ed, V3.01"
+  wasDerivedFrom: "SI Brochure 9th ed, V3.02"
 data:
 - URI: becquerel
   prefLabel_fr: becquerel