diff --git a/include/nat.h b/include/nat.h
index e9b5c61d..55bf56fb 100644
--- a/include/nat.h
+++ b/include/nat.h
@@ -180,7 +180,6 @@ extern char *relates[];
 #define putrealm(p) ef_write(EF_REALM, (p)->r_uid, (p))
 
 extern double tfact(natid cn, double mult);
-extern double tfactfire(natid cn, double mult);
 extern double techfact(int level, double mult);
 
 extern char *cname(natid n);
diff --git a/src/lib/common/tfact.c b/src/lib/common/tfact.c
index bd61d5f9..cf814030 100644
--- a/src/lib/common/tfact.c
+++ b/src/lib/common/tfact.c
@@ -50,18 +50,6 @@ tfact(natid cn, double mult)
     return mult * tlev;
 }
 
-double
-tfactfire(natid cn, double mult)
-{
-    double tlev;
-    struct natstr *np;
-
-    np = getnatp(cn);
-    tlev = np->nat_level[NAT_TLEV];
-    tlev = (50.0 + tlev) / (200.0 + tlev);
-    return mult * tlev * fire_range_factor;
-}
-
 double
 techfact(int level, double mult)
 {