diff --git a/uefi-test-runner/src/boot/misc.rs b/uefi-test-runner/src/boot/misc.rs
index 228af5bf..40b61bb0 100644
--- a/uefi-test-runner/src/boot/misc.rs
+++ b/uefi-test-runner/src/boot/misc.rs
@@ -2,7 +2,7 @@
 
 use core::ffi::c_void;
 use core::ptr::{self, NonNull};
-
+use core::time::Duration;
 use uefi::boot::{
     EventType, OpenProtocolAttributes, OpenProtocolParams, SearchType, TimerTrigger, Tpl,
 };
@@ -55,7 +55,11 @@ fn test_timer() {
     let timer_event =
         unsafe { boot::create_event_ex(EventType::TIMER, Tpl::CALLBACK, None, None, None) }
             .unwrap();
-    boot::set_timer(&timer_event, TimerTrigger::Relative(5_0 /*00 ns */)).unwrap();
+    boot::set_timer(
+        &timer_event,
+        TimerTrigger::Relative(Duration::from_nanos(5_000)),
+    )
+    .unwrap();
     let mut events = [unsafe { timer_event.unsafe_clone() }];
     assert_eq!(boot::wait_for_event(&mut events).unwrap(), 0);
 
diff --git a/uefi/CHANGELOG.md b/uefi/CHANGELOG.md
index 5df212f8..b0b1f63d 100644
--- a/uefi/CHANGELOG.md
+++ b/uefi/CHANGELOG.md
@@ -3,7 +3,7 @@
 ## Added
 
 ## Changed
-
+- **Breaking:** The variants of `TimerTrigger` now hold a `Duration`
 
 # uefi - v0.37.0 (2026-03-22)
 
diff --git a/uefi/src/boot.rs b/uefi/src/boot.rs
index 5f9a44f3..c73f5fc1 100644
--- a/uefi/src/boot.rs
+++ b/uefi/src/boot.rs
@@ -593,10 +593,11 @@ pub fn set_timer(event: &Event, trigger_time: TimerTrigger) -> Result {
     let bt = boot_services_raw_panicking();
     let bt = unsafe { bt.as_ref() };
 
-    let (ty, time) = match trigger_time {
-        TimerTrigger::Cancel => (TimerDelay::CANCEL, 0),
-        TimerTrigger::Periodic(period) => (TimerDelay::PERIODIC, period),
-        TimerTrigger::Relative(delay) => (TimerDelay::RELATIVE, delay),
+    let time = trigger_time.to_100ns_steps();
+    let ty = match trigger_time {
+        TimerTrigger::Cancel => TimerDelay::CANCEL,
+        TimerTrigger::Periodic(_) => TimerDelay::PERIODIC,
+        TimerTrigger::Relative(_) => TimerDelay::RELATIVE,
     };
     unsafe { (bt.set_timer)(event.as_ptr(), ty, time) }.to_result()
 }
@@ -1937,28 +1938,74 @@ pub type EventNotifyFn = unsafe extern "efiapi" fn(event: Event, context: Option
 /// See [`set_timer`].
 ///
 /// [`TIMER`]: EventType::TIMER
-#[derive(Debug)]
+#[derive(Copy, Clone, Debug)]
 pub enum TimerTrigger {
     /// Remove the event's timer setting.
     Cancel,
 
     /// Trigger the event periodically.
     Periodic(
-        /// Duration between event signaling in units of 100ns. If set to zero,
-        /// the event will be signaled on every timer tick.
-        u64,
+        /// Duration to wait before the next event is fired.
+        ///
+        /// If set to zero, the event will be signaled on every timer tick.
+        Duration,
     ),
 
     /// Trigger the event one time.
     Relative(
-        /// Duration to wait before signaling the event in units of 100ns. If
-        /// set to zero, the event will be signaled on the next timer tick.
-        u64,
+        /// Duration to wait before the next event is fired.
+        ///
+        /// If set to zero, the event will be signaled on every timer tick.
+        Duration,
     ),
 }
 
+impl TimerTrigger {
+    /// Transforms the underlying value to 100ns steps, a format widely used
+    /// in EFI APIs.
+    #[must_use]
+    pub fn to_100ns_steps(self) -> u64 {
+        const NANOS_PER_STEP: u128 = 100;
+        match self {
+            Self::Cancel => 0,
+            Self::Periodic(dur) => {
+                let ns100_steps = dur.as_nanos().div_ceil(NANOS_PER_STEP);
+                u64::try_from(ns100_steps).expect("should be representable as u64")
+            }
+            Self::Relative(dur) => {
+                let ns100_steps = dur.as_nanos().div_ceil(NANOS_PER_STEP);
+                u64::try_from(ns100_steps).expect("should be representable as u64")
+            }
+        }
+    }
+}
+
 /// Opaque pointer returned by [`register_protocol_notify`] to be used
 /// with [`locate_handle`] via [`SearchType::ByRegisterNotify`].
 #[derive(Debug, Clone, Copy)]
 #[repr(transparent)]
 pub struct ProtocolSearchKey(pub(crate) NonNull<c_void>);
+
+#[cfg(test)]
+mod tests {
+    use core::time::Duration;
+    use uefi::boot::TimerTrigger;
+
+    #[test]
+    fn test_timer_trigger_100ns_steps() {
+        let trigger = TimerTrigger::Periodic(Duration::from_nanos(0));
+        assert_eq!(trigger.to_100ns_steps(), 0);
+        let trigger = TimerTrigger::Relative(Duration::from_nanos(0));
+        assert_eq!(trigger.to_100ns_steps(), 0);
+
+        let trigger = TimerTrigger::Periodic(Duration::from_nanos(12_300));
+        assert_eq!(trigger.to_100ns_steps(), 123);
+        let trigger = TimerTrigger::Relative(Duration::from_nanos(12_300));
+        assert_eq!(trigger.to_100ns_steps(), 123);
+
+        let trigger = TimerTrigger::Periodic(Duration::from_secs(42));
+        assert_eq!(trigger.to_100ns_steps(), 420000000);
+        let trigger = TimerTrigger::Relative(Duration::from_secs(42));
+        assert_eq!(trigger.to_100ns_steps(), 420000000);
+    }
+}