diff --git a/ext/io/event/selector/epoll.c b/ext/io/event/selector/epoll.c
index 82fee3c6..5c1f2f40 100644
--- a/ext/io/event/selector/epoll.c
+++ b/ext/io/event/selector/epoll.c
@@ -786,24 +786,21 @@ struct timespec * make_timeout(VALUE duration, struct timespec * storage) {
 		return NULL;
 	}
 	
-	if (RB_FLOAT_TYPE_P(duration)) {
-		double value = RFLOAT_VALUE(duration);
-		time_t seconds = value;
-		
-		storage->tv_sec = seconds;
-		storage->tv_nsec = (value - seconds) * 1000000000L;
-		
-		return storage;
-	}
-	
-	else if (RB_INTEGER_TYPE_P(duration)) {
+	if (RB_INTEGER_TYPE_P(duration)) {
 		storage->tv_sec = NUM2TIMET(duration);
 		storage->tv_nsec = 0;
 		
 		return storage;
 	}
 	
-	rb_raise(rb_eArgError, "unable to convert timeout: %"PRIsVALUE, rb_inspect(duration));
+	duration = rb_to_float(duration);
+	double value = RFLOAT_VALUE(duration);
+	time_t seconds = value;
+	
+	storage->tv_sec = seconds;
+	storage->tv_nsec = (value - seconds) * 1000000000L;
+	
+	return storage;
 }
 
 static
diff --git a/ext/io/event/selector/kqueue.c b/ext/io/event/selector/kqueue.c
index fb5a40e4..699439b0 100644
--- a/ext/io/event/selector/kqueue.c
+++ b/ext/io/event/selector/kqueue.c
@@ -799,24 +799,21 @@ struct timespec * make_timeout(VALUE duration, struct timespec * storage) {
 		return NULL;
 	}
 	
-	if (RB_FLOAT_TYPE_P(duration)) {
-		double value = RFLOAT_VALUE(duration);
-		time_t seconds = value;
-		
-		storage->tv_sec = seconds;
-		storage->tv_nsec = (value - seconds) * 1000000000L;
-		
-		return storage;
-	}
-	
-	else if (RB_INTEGER_TYPE_P(duration)) {
+	if (RB_INTEGER_TYPE_P(duration)) {
 		storage->tv_sec = NUM2TIMET(duration);
 		storage->tv_nsec = 0;
 		
 		return storage;
 	}
 	
-	rb_raise(rb_eArgError, "unable to convert timeout: %"PRIsVALUE, rb_inspect(duration));
+	duration = rb_to_float(duration);
+	double value = RFLOAT_VALUE(duration);
+	time_t seconds = value;
+	
+	storage->tv_sec = seconds;
+	storage->tv_nsec = (value - seconds) * 1000000000L;
+	
+	return storage;
 }
 
 static
diff --git a/ext/io/event/selector/uring.c b/ext/io/event/selector/uring.c
index a753cd47..33f1c3ae 100644
--- a/ext/io/event/selector/uring.c
+++ b/ext/io/event/selector/uring.c
@@ -901,24 +901,21 @@ struct __kernel_timespec * make_timeout(VALUE duration, struct __kernel_timespec
 		return NULL;
 	}
 	
-	if (RB_FLOAT_TYPE_P(duration)) {
-		double value = RFLOAT_VALUE(duration);
-		time_t seconds = value;
-		
-		storage->tv_sec = seconds;
-		storage->tv_nsec = (value - seconds) * 1000000000L;
-		
-		return storage;
-	}
-	
-	else if (RB_INTEGER_TYPE_P(duration)) {
+	if (RB_INTEGER_TYPE_P(duration)) {
 		storage->tv_sec = NUM2TIMET(duration);
 		storage->tv_nsec = 0;
 		
 		return storage;
 	}
 	
-	rb_raise(rb_eArgError, "unable to convert timeout: %"PRIsVALUE, rb_inspect(duration));
+	duration = rb_to_float(duration);
+	double value = RFLOAT_VALUE(duration);
+	time_t seconds = value;
+	
+	storage->tv_sec = seconds;
+	storage->tv_nsec = (value - seconds) * 1000000000L;
+	
+	return storage;
 }
 
 static
diff --git a/test/io/event/selector.rb b/test/io/event/selector.rb
index 3d087c52..c8c93fb2 100644
--- a/test/io/event/selector.rb
+++ b/test/io/event/selector.rb
@@ -49,7 +49,7 @@ def transfer
 		it "raises an error when given an invalid duration" do
 			expect do
 				selector.select("invalid")
-			end.to raise_exception(ArgumentError)
+			end.to raise_exception(TypeError)
 		end
 	end