diff --git a/code/WorkInProgress/Cael_Aislinn/Rust/core_field.dm b/code/WorkInProgress/Cael_Aislinn/Rust/core_field.dm
index cd397e1095..cf41b2c61f 100644
--- a/code/WorkInProgress/Cael_Aislinn/Rust/core_field.dm
+++ b/code/WorkInProgress/Cael_Aislinn/Rust/core_field.dm
@@ -111,7 +111,7 @@ Deuterium-tritium fusion: 4.5 x 10^7 K
 	//init values
 	major_radius = field_strength * 0.21875// max = 8.75
 	minor_radius = field_strength * 0.2125// max = 8.625
-	volume_covered = PI * major_radius * minor_radius * 2.5 * 2.5 * 1000
+	volume_covered = M_PI * major_radius * minor_radius * 2.5 * 2.5 * 1000
 
 	processing_objects.Add(src)
 
@@ -131,7 +131,7 @@ Deuterium-tritium fusion: 4.5 x 10^7 K
 	var/transfer_ratio = field_strength / 50			//higher field strength will result in faster phoron aggregation
 	major_radius = field_strength * 0.21875// max = 8.75m
 	minor_radius = field_strength * 0.2125// max = 8.625m
-	volume_covered = PI * major_radius * minor_radius * 2.5 * 2.5 * 2.5 * 7 * 7 * transfer_ratio	//one tile = 2.5m*2.5m*2.5m
+	volume_covered = M_PI * major_radius * minor_radius * 2.5 * 2.5 * 2.5 * 7 * 7 * transfer_ratio	//one tile = 2.5m*2.5m*2.5m
 
 	//add phoron from the surrounding environment
 	var/datum/gas_mixture/environment = loc.return_air()
diff --git a/code/game/objects/effects/chemsmoke.dm b/code/game/objects/effects/chemsmoke.dm
index e62623e2ec..d6d0ac0169 100644
--- a/code/game/objects/effects/chemsmoke.dm
+++ b/code/game/objects/effects/chemsmoke.dm
@@ -165,7 +165,7 @@
 			continue
 
 		var/offset = 0
-		var/points = round((radius * 2 * PI) / arcLength)
+		var/points = round((radius * 2 * M_PI) / arcLength)
 		var/angle = round(ToDegrees(arcLength / radius), 1)
 
 		if(!IsInteger(radius))
diff --git a/code/setup.dm b/code/setup.dm
index 9b5a341b7c..c69b6152a6 100644
--- a/code/setup.dm
+++ b/code/setup.dm
@@ -1,9 +1,9 @@
 #define DEBUG
 
 // Math constants.
-#define E     2.71828183
-#define PI    3.14159265
-#define Sqrt2 1.41421356
+#define M_E     2.71828183
+#define M_PI    3.14159265
+#define M_SQRT2 1.41421356
 
 #define R_IDEAL_GAS_EQUATION       8.31    // kPa*L/(K*mol).
 #define ONE_ATMOSPHERE             101.325 // kPa.