diff --git a/modules/local/samplesheet_check.nf b/modules/local/samplesheet_check.nf
index 234c62b1..6983b1fa 100644
--- a/modules/local/samplesheet_check.nf
+++ b/modules/local/samplesheet_check.nf
@@ -1,5 +1,6 @@
 process SAMPLESHEET_CHECK {
     tag "$samplesheet"
+    label 'process_single'
 
     conda (params.enable_conda ? "conda-forge::python=3.8.3" : null)
     container "${ workflow.containerEngine == 'singularity' && !task.ext.singularity_pull_docker_container ?
@@ -13,6 +14,9 @@ process SAMPLESHEET_CHECK {
     path '*.csv'       , emit: csv
     path "versions.yml", emit: versions
 
+    when:
+    task.ext.when == null || task.ext.when
+
     script: // This script is bundled with the pipeline, in nf-core/methylseq/bin/
     // def reference = params.fasta ? "--genome ${params.fasta}" : ""
     """