diff --git a/commons/passive/polar/polar_heart_rate.avsc b/commons/passive/polar/polar_heart_rate.avsc
index acc078c0..b13dd0b2 100644
--- a/commons/passive/polar/polar_heart_rate.avsc
+++ b/commons/passive/polar/polar_heart_rate.avsc
@@ -5,7 +5,7 @@
   "doc": "Heart rate as beats per minute.",
   "fields": [
     { "name": "deviceName", "type": "string", "doc": "Polar device name" },
-    { "name": "time", "type": "double", "doc": "Device receiver timestamp in UTC (s)." },
+    { "name": "time", "type": "long", "doc": "Device receiver timestamp in UTC (ns)." },
     { "name": "timeReceived", "type": "double", "doc": "Device receiver timestamp in UTC (s)." },
     { "name": "heartRate", "type": "int", "doc": "Heart rate (bpm)." },
     { "name": "rrsMs", "type": {"type": "array", "items": "int"}, "doc": "Data for rrsMs." },