rad flags fixes.

code/__DEFINES/flags.dm

@@ -90,3 +90,4 @@ GLOBAL_LIST_INIT(bitflags, list(1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 204
 // radiation
 #define RAD_PROTECT_CONTENTS (1<<0)
 #define RAD_NO_CONTAMINATE (1<<1)
+#define RAD_PROTECT_SELF (1<<2)

code/__HELPERS/radiation.dm

@@ -15,7 +15,7 @@
 	while(processing_list.len)
 		var/atom/thing = processing_list[1]
 		processing_list -= thing
-		if(ignored_things[thing.type])
+		if(ignored_things[thing.type] || CHECK_BITFIELD(thing.rad_flags, RAD_PROTECT_SELF))
 			continue
 		. += thing
 		if((thing.rad_flags & RAD_PROTECT_CONTENTS) || (SEND_SIGNAL(thing, COMSIG_ATOM_RAD_PROBE) & COMPONENT_BLOCK_RADIATION))

code/datums/radiation_wave.dm

@@ -66,6 +66,8 @@
 		place = cmaster_turf
 		for(var/i in 1 to distance)
 			place = get_step(place, dir)
+			if(!place)
+				break
 			atoms += get_rad_contents(place)
 
 	return atoms
@@ -108,7 +110,7 @@
 		if(!can_contaminate || blacklisted[thing.type])
 			continue
 		if(prob(contamination_chance)) // Only stronk rads get to have little baby rads
-			if(SEND_SIGNAL(thing, COMSIG_ATOM_RAD_CONTAMINATING, strength) & COMPONENT_BLOCK_CONTAMINATION)
+			if(CHECK_BITFIELD(thing.rad_flags, RAD_NO_CONTAMINATE) || SEND_SIGNAL(thing, COMSIG_ATOM_RAD_CONTAMINATING, strength) & COMPONENT_BLOCK_CONTAMINATION)
 				continue
 			var/rad_strength = (strength-RAD_MINIMUM_CONTAMINATION) * RAD_CONTAMINATION_STR_COEFFICIENT
 			thing.AddComponent(/datum/component/radioactive, rad_strength, source)