diff --git a/wmdr/ObservingMethodAtmosphere/344.ttl b/wmdr/ObservingMethodAtmosphere/344.ttl
index c3995010..0664d8c2 100644
--- a/wmdr/ObservingMethodAtmosphere/344.ttl
+++ b/wmdr/ObservingMethodAtmosphere/344.ttl
@@ -3,6 +3,6 @@
 @prefix dct: <http://purl.org/dc/terms/> . 
 
 <344> a skos:Concept ;
-	rdfs:label "trace gases" ;
+	rdfs:label "GC-CVAFS" ;
 	skos:notation "344" ;
-	dct:description "greenhouse gas"@en	.
+	dct:description "Gas chromatography and detection by cold vapour atomic fluorescence spectrometry."@en	.
diff --git a/wmdr/ObservingMethodAtmosphere/345.ttl b/wmdr/ObservingMethodAtmosphere/345.ttl
index 622b0147..351b7c6d 100644
--- a/wmdr/ObservingMethodAtmosphere/345.ttl
+++ b/wmdr/ObservingMethodAtmosphere/345.ttl
@@ -3,6 +3,6 @@
 @prefix dct: <http://purl.org/dc/terms/> . 
 
 <345> a skos:Concept ;
-	rdfs:label "trace gases" ;
+	rdfs:label "GC-TCD" ;
 	skos:notation "345" ;
-	dct:description "greenhouse gas"@en	.
+	dct:description "Gas chromatography and detection by a thermal conductivity detector."@en	.
diff --git a/wmdr/ObservingMethodAtmosphere/346.ttl b/wmdr/ObservingMethodAtmosphere/346.ttl
index 521a478d..782d1892 100644
--- a/wmdr/ObservingMethodAtmosphere/346.ttl
+++ b/wmdr/ObservingMethodAtmosphere/346.ttl
@@ -3,6 +3,6 @@
 @prefix dct: <http://purl.org/dc/terms/> . 
 
 <346> a skos:Concept ;
-	rdfs:label "trace gases" ;
+	rdfs:label "Electrostatic collection + alpha counting" ;
 	skos:notation "346" ;
-	dct:description "in situ"@en	.
+	dct:description "Alpha counting after electrostatic collection of measurand."@en	.
diff --git a/wmdr/ObservingMethodAtmosphere/347.ttl b/wmdr/ObservingMethodAtmosphere/347.ttl
index cc423b7a..cba4c5ad 100644
--- a/wmdr/ObservingMethodAtmosphere/347.ttl
+++ b/wmdr/ObservingMethodAtmosphere/347.ttl
@@ -3,6 +3,6 @@
 @prefix dct: <http://purl.org/dc/terms/> . 
 
 <347> a skos:Concept ;
-	rdfs:label "trace gases" ;
+	rdfs:label "Tunable Infrared Laser Differential Absorption Spectroscopy (TILDAS)" ;
 	skos:notation "347" ;
-	dct:description "in situ"@en	.
+	dct:description "Tunable Infrared Laser Differential Absorption Spectroscopy (TILDAS)."@en	.
diff --git a/wmdr/ObservingMethodAtmosphere/348.ttl b/wmdr/ObservingMethodAtmosphere/348.ttl
index 5cb83eaa..304edf19 100644
--- a/wmdr/ObservingMethodAtmosphere/348.ttl
+++ b/wmdr/ObservingMethodAtmosphere/348.ttl
@@ -3,6 +3,6 @@
 @prefix dct: <http://purl.org/dc/terms/> . 
 
 <348> a skos:Concept ;
-	rdfs:label "trace gases" ;
+	rdfs:label "Radionuclide decay counting [general]" ;
 	skos:notation "348" ;
-	dct:description "in situ"@en	.
+	dct:description "Determination of the counts measured per unit time as a result of radionuclide decay."@en	.
diff --git a/wmdr/ObservingMethodAtmosphere/349.ttl b/wmdr/ObservingMethodAtmosphere/349.ttl
index 31ac6b73..40fbba6c 100644
--- a/wmdr/ObservingMethodAtmosphere/349.ttl
+++ b/wmdr/ObservingMethodAtmosphere/349.ttl
@@ -3,6 +3,6 @@
 @prefix dct: <http://purl.org/dc/terms/> . 
 
 <349> a skos:Concept ;
-	rdfs:label "trace gases" ;
+	rdfs:label "IR-GFC" ;
 	skos:notation "349" ;
-	dct:description "in situ"@en	.
+	dct:description "Infrared absorption measurement based on the gas-filter correlation technique, a specifique variant of NDIR."@en	.