diff --git a/sdrf_pipelines/sdrf/sdrf_schema.py b/sdrf_pipelines/sdrf/sdrf_schema.py
index a2bb22b..34b5371 100644
--- a/sdrf_pipelines/sdrf/sdrf_schema.py
+++ b/sdrf_pipelines/sdrf/sdrf_schema.py
@@ -3,7 +3,6 @@
 import typing
 from typing import Any
 
-import numpy as np
 import pandas as pd
 from pandas_schema import Column
 from pandas_schema import Schema