diff --git a/base_classes/NXsample.nxdl.xml b/base_classes/NXsample.nxdl.xml
index 10717cb594..0d720a8f54 100644
--- a/base_classes/NXsample.nxdl.xml
+++ b/base_classes/NXsample.nxdl.xml
@@ -36,6 +36,17 @@
 		<symbol name="n_mField"><doc>number of values in applied magnetic field</doc></symbol>
 		<symbol name="n_pField"><doc>number of values in applied pressure field</doc></symbol>
 		<symbol name="n_sField"><doc>number of values in applied stress field</doc></symbol>
+		<symbol name="n_pH"><doc>number of pH values</doc></symbol>
+		<symbol name="n_curr"><doc>number of current values</doc></symbol>
+		<symbol name="n_cond"><doc>number of conductivity values</doc></symbol>
+		<symbol name="n_resist"><doc>number of resistance values</doc></symbol>
+		<symbol name="n_volt"><doc>number of voltage values</doc></symbol>
+		<symbol name="n_flow"><doc>number of flow rates</doc></symbol>
+		<symbol name="n_strainField"><doc>number of values in applied strain field</doc></symbol>
+		<symbol name="n_shearField"><doc>number of shear values</doc></symbol>
+		<symbol name="n_spField"><doc>number of values in applied surface pressure field</doc></symbol>
+		<symbol name="n_hum"><doc>number of humidity values</doc></symbol>
+		<symbol name="n_vis"><doc>number of viscosity values</doc></symbol>
 	</symbols>
 
 	<doc>
@@ -121,6 +132,93 @@
 			<dim index="1" value="n_pField"/><!-- could be any length -->
 		</dimensions>
 	</field>
+	<field name="pH" type="NX_FLOAT" units="NX_MOLAR_DENSITY">
+		<doc>Sample pH value</doc>
+		<dimensions>
+			<dim index="1" value="n_pH"/><!-- could be any length -->
+		</dimensions>
+	</field>
+	<field name="current" type="NX_FLOAT" units="NX_CURRENT">
+		<doc>Applied current</doc>
+		<dimensions>
+			<dim index="1" value="n_curr"/><!-- could be any length -->
+		</dimensions>
+	</field>
+	<field name="conductivity" type="NX_FLOAT" units="NX_CONDUCTIVITY">
+		<doc>Sample electrical conductivity</doc>
+		<dimensions>
+			<dim index="1" value="n_cond"/><!-- could be any length -->
+		</dimensions>
+	</field>
+	<field name="resistance" type="NX_FLOAT" units="NX_RESISTANCE">
+		<doc>Sample electrical resistance</doc>
+		<dimensions>
+			<dim index="1" value="n_resist"/><!-- could be any length -->
+		</dimensions>
+	</field>
+	<field name="voltage" type="NX_FLOAT" units="NX_VOLTAGE">
+		<doc>Applied voltage</doc>
+		<dimensions>
+			<dim index="1" value="n_volt"/><!-- could be any length -->
+		</dimensions>
+	</field>
+	<field name="flow" type="NX_FLOAT" units="NX_FLOW">
+		<doc>Sample flow rate</doc>
+		<dimensions>
+			<dim index="1" value="n_flow"/><!-- could be any length -->
+		</dimensions>
+	</field>
+	<field name="strain_field" type="NX_FLOAT" units="NX_DIMENSIONLESS">
+		<doc>Sample strain field</doc>
+		<dimensions>
+			<dim index="1" value="n_strainField"/><!-- could be any length -->
+		</dimensions>
+		<attribute name="direction">
+        	<enumeration>
+        		<item value="x"/>
+        		<item value="y"/>
+        		<item value="z"/>
+        	</enumeration>
+        </attribute>
+	</field>
+	<field name="shear_field" type="NX_FLOAT" units="NX_PRESSURE">
+		<doc>Sample shear stress field</doc>
+		<dimensions>
+			<dim index="1" value="n_shearField"/><!-- could be any length -->
+		</dimensions>
+		<attribute name="direction">
+        	<enumeration>
+        		<item value="x"/>
+        		<item value="y"/>
+        		<item value="z"/>
+        	</enumeration>
+        </attribute>
+	</field>
+	<field name="surface_pressure" type="NX_FLOAT" units="NX_PRESSURE">
+		<doc>Sample surface pressure field</doc>
+		<dimensions>
+			<dim index="1" value="n_spField"/><!-- could be any length -->
+		</dimensions>
+		<attribute name="direction">
+        	<enumeration>
+        		<item value="x"/>
+        		<item value="y"/>
+        		<item value="z"/>
+        	</enumeration>
+        </attribute>
+	</field>
+	<field name="humidity" type="NX_FLOAT" units="NX_DIMENSIONLESS">
+		<doc>Sample humidity</doc>
+		<dimensions>
+			<dim index="1" value="n_hum"/><!-- could be any length -->
+		</dimensions>
+	</field>
+	<field name="viscosity" type="NX_FLOAT" units="NX_PRESSURE_TIME">
+		<doc>Sample viscosity</doc>
+		<dimensions>
+			<dim index="1" value="n_vis"/><!-- could be any length -->
+		</dimensions>
+	</field>
 	<field name="changer_position" type="NX_INT" units="NX_UNITLESS">
 		<doc>Sample changer position</doc>
 	</field>
@@ -338,9 +436,6 @@
 	<group name="temperature_env" type="NXenvironment">
 		<doc>Additional sample temperature environment information</doc>
 	</group>
-	<group name="magnetic_field" type="NXlog">
-		<doc>magnetic_field.value is a link to e.g. magnetic_field_env.sensor1.value</doc>
-	</group>
 	<group name="magnetic_field_log" type="NXlog"
 		deprecated="use ``magnetic_field``, see: https://github.com/nexusformat/definitions/issues/816">
 		<doc>magnetic_field_log.value is a link to e.g. magnetic_field_env.sensor1.value_log.value</doc>
@@ -348,6 +443,51 @@
 	<group name="magnetic_field_env" type="NXenvironment">
 		<doc>Additional sample magnetic environment information</doc>
 	</group>
+	<group name="pH_env" type="NXenvironment">
+		<doc>Additional sample pH environment information</doc>
+	</group>
+	<group name="pressure_env" type="NXenvironment">
+		<doc>Additional sample pressure environment information</doc>
+	</group>
+	<group name="electric_field_env" type="NXenvironment">
+		<doc>Additional sample electric field environment information</doc>
+	</group>
+	<group name="current_env" type="NXenvironment">
+		<doc>Additional sample current environment information</doc>
+	</group>
+	<group name="conductivity_env" type="NXenvironment">
+		<doc>Additional sample conductivity environment information</doc>
+	</group>
+	<group name="resistance_env" type="NXenvironment">
+		<doc>Additional sample resistance environment information</doc>
+	</group>
+	<group name="voltage_env" type="NXenvironment">
+		<doc>Additional sample voltage environment information</doc>
+	</group>
+	<group name="flow_env" type="NXenvironment">
+		<doc>Additional sample flow environment information</doc>
+	</group>
+	<group name="stress_field_env" type="NXenvironment">
+		<doc>Additional sample stress field environment information</doc>
+	</group>
+	<group name="strain_field_env" type="NXenvironment">
+		<doc>Additional sample strain field environment information</doc>
+	</group>
+	<group name="shear_field_env" type="NXenvironment">
+		<doc>Additional sample shear stress field environment information</doc>
+	</group>
+	<group name="surface_pressure_env" type="NXenvironment">
+		<doc>Additional sample surface pressure field environment information</doc>
+	</group>
+	<group name="humidity_env" type="NXenvironment">
+		<doc>Additional sample humidity environment information</doc>
+	</group>
+	<group name="viscosity_env" type="NXenvironment">
+		<doc>Additional sample viscosity environment information</doc>
+	</group>
+	<group name="concentration_env" type="NXenvironment">
+		<doc>Additional sample concentration environment information</doc>
+	</group>
 	<field name="external_DAC" type="NX_FLOAT" units="NX_ANY">
 		<doc>value sent to user's sample setup</doc>
 	</field>
diff --git a/base_classes/NXsensor.nxdl.xml b/base_classes/NXsensor.nxdl.xml
index d46d176038..c80ab33b29 100644
--- a/base_classes/NXsensor.nxdl.xml
+++ b/base_classes/NXsensor.nxdl.xml
@@ -40,6 +40,11 @@
 	<field name="short_name">
 		<doc>Short name of sensor used e.g. on monitor display program</doc>
 	</field>
+	<field name="description">
+		<doc>
+			Description of the sensor
+		</doc>
+	</field>
 	<field name="attached_to">
 		<doc>where sensor is attached to ("sample" | "can")</doc>
 	</field>
@@ -65,6 +70,9 @@
 			<item value="strain" />
 			<item value="shear" />
 			<item value="surface_pressure" />
+			<item value="humidity" />
+			<item value="viscosity" />
+			<item value="concentration" />
 		</enumeration>
 	</field>
 	<field name="type">
@@ -102,8 +110,8 @@
 	</field>
 	<field name="value" type="NX_FLOAT" units="NX_ANY">
 		<doc>
-			nominal setpoint or average value 
-			- need [n] as may be a vector
+			Average value of the sensor - need [n] as may be a vector.
+			For a nominal setpoint use the generally defined value_set field.
 		</doc>
 		<dimensions>
 			<dim index="1" value="n"/>
@@ -111,7 +119,7 @@
 	</field>
 	<field name="value_deriv1" type="NX_FLOAT" units="NX_ANY">
 		<doc>
-			Nominal/average first derivative of value 
+			Average first derivative of value
 			e.g. strain rate 
 			- same dimensions as "value" (may be a vector)
 		</doc>
@@ -121,7 +129,7 @@
 	</field>
 	<field name="value_deriv2" type="NX_FLOAT" units="NX_ANY">
 		<doc>
-			Nominal/average second derivative of value
+			Average second derivative of value
 			- same dimensions as "value" (may be a vector)
 		</doc>
 		<dimensions>
diff --git a/nxdlTypes.xsd b/nxdlTypes.xsd
index b9c972571d..6e07e954a6 100644
--- a/nxdlTypes.xsd
+++ b/nxdlTypes.xsd
@@ -54,23 +54,28 @@
 			nxdl:NX_AREA
 			nxdl:NX_CROSS_SECTION
 			nxdl:NX_CHARGE
+			nxdl:NX_CONDUCTIVITY
+			nxdl:NX_COUNT
 			nxdl:NX_CURRENT
 			nxdl:NX_DIMENSIONLESS
 			nxdl:NX_EMITTANCE
 			nxdl:NX_ENERGY
+			nxdl:NX_FLOW
 			nxdl:NX_FLUX
 			nxdl:NX_FREQUENCY
 			nxdl:NX_LENGTH
 			nxdl:NX_MASS
 			nxdl:NX_MASS_DENSITY
+			nxdl:NX_MOLAR_DENSITY
 			nxdl:NX_MOLECULAR_WEIGHT
 			nxdl:NX_PER_AREA
 			nxdl:NX_PER_LENGTH
 			nxdl:NX_PERIOD
 			nxdl:NX_POWER 
 			nxdl:NX_PRESSURE
+			nxdl:NX_PRESSURE_TIME
 			nxdl:NX_PULSES
-			nxdl:NX_COUNT
+			nxdl:NX_RESISTANCE
 			nxdl:NX_SCATTERING_LENGTH_DENSITY
 			nxdl:NX_SOLID_ANGLE
 			nxdl:NX_TEMPERATURE
@@ -115,7 +120,17 @@
 		</xs:annotation>
 		<xs:restriction base="xs:string" />
 	</xs:simpleType>
-	
+
+	<xs:simpleType name="NX_CONDUCTIVITY">
+		<xs:annotation>
+			<xs:documentation>
+				units of electrical conductivity
+				<xs:element name="example">S/m</xs:element>
+			</xs:documentation>
+		</xs:annotation>
+		<xs:restriction base="xs:string" />
+	</xs:simpleType>
+
 	<xs:simpleType name="NX_COUNT">
 		<xs:annotation>
 			<xs:documentation>
@@ -188,7 +203,17 @@
 		</xs:annotation>
 		<xs:restriction base="xs:string" />
 	</xs:simpleType>
-	
+
+	<xs:simpleType name="NX_FLOW">
+		<xs:annotation>
+			<xs:documentation>
+				units of volumetric or mass flow rate
+				<xs:element name="example">m^3/s, kg/s</xs:element>
+			</xs:documentation>
+		</xs:annotation>
+		<xs:restriction base="xs:string" />
+	</xs:simpleType>
+
 	<xs:simpleType name="NX_FLUX">
 		<xs:annotation>
 			<xs:documentation>
@@ -238,6 +263,16 @@
 		</xs:annotation>
 		<xs:restriction base="xs:string" />
 	</xs:simpleType>
+
+	<xs:simpleType name="NX_MOLAR_DENSITY">
+		<xs:annotation>
+			<xs:documentation>
+				units of molar concentration
+				<xs:element name="example">mol/L</xs:element>
+			</xs:documentation>
+		</xs:annotation>
+		<xs:restriction base="xs:string" />
+	</xs:simpleType>
 	
 	<xs:simpleType name="NX_MOLECULAR_WEIGHT">
 		<xs:annotation>
@@ -299,7 +334,17 @@
 		</xs:annotation>
 		<xs:restriction base="xs:string" />
 	</xs:simpleType>
-	
+
+	<xs:simpleType name="NX_PRESSURE_TIME">
+		<xs:annotation>
+			<xs:documentation>
+				units of pressure multiplied by time
+				<xs:element name="example">Pa * s</xs:element>
+			</xs:documentation>
+		</xs:annotation>
+		<xs:restriction base="xs:string" />
+	</xs:simpleType>
+
 	<xs:simpleType name="NX_PULSES">
 		<xs:annotation>
 			<xs:documentation>
@@ -310,7 +355,17 @@
 		</xs:annotation>
 		<xs:restriction base="xs:string" />
 	</xs:simpleType>
-	
+
+	<xs:simpleType name="NX_RESISTANCE">
+		<xs:annotation>
+			<xs:documentation>
+				units of electrical resistance
+				<xs:element name="example">ohm</xs:element>
+			</xs:documentation>
+		</xs:annotation>
+		<xs:restriction base="xs:string" />
+	</xs:simpleType>
+
 	<xs:simpleType name="NX_SCATTERING_LENGTH_DENSITY">
 		<xs:annotation>
 			<xs:documentation>