diff --git a/src/GRANULAR/fix_pour.cpp b/src/GRANULAR/fix_pour.cpp
index 613dd61496..9d990fd7ba 100644
--- a/src/GRANULAR/fix_pour.cpp
+++ b/src/GRANULAR/fix_pour.cpp
@@ -114,14 +114,13 @@ FixPour::FixPour(LAMMPS *lmp, int narg, char **arg) :
     } else error->all("Illegal fix pour command");
   }
 
-  // error check that a valid region was specified
+  // error checks on region and its extent being inside simulation box
 
   if (iregion == -1) error->all("Must specify a region in fix pour");
-
-  // error checks on region
-
-  if (domain->regions[iregion]->interior == 0)
-    error->all("Must use region with side = in with fix pour");
+  if (domain->regions[iregion]->bboxflag == 0)
+    error->all("Fix pour region does not support a bounding box");
+  if (domain->regions[iregion]->dynamic_check())
+    error->all("Fix pour region cannot be dynamic");
 
   if (strcmp(domain->regions[iregion]->style,"block") == 0) {
     region_style = 1;
diff --git a/src/PRD/prd.cpp b/src/PRD/prd.cpp
index 00690f838f..8dabbca99d 100644
--- a/src/PRD/prd.cpp
+++ b/src/PRD/prd.cpp
@@ -24,6 +24,7 @@
 #include "update.h"
 #include "atom.h"
 #include "domain.h"
+#include "region.h"
 #include "comm.h"
 #include "velocity.h"
 #include "integrate.h"
@@ -221,12 +222,16 @@ void PRD::command(int narg, char **arg)
 
   update->minimize->init();
 
-  // cannot use PRD with time-dependent fixes
+  // cannot use PRD with time-dependent fixes or regions
 
   for (int i = 0; i < modify->nfix; i++)
     if (modify->fix[i]->time_depend)
       error->all("Cannot use PRD with a time-dependent fix defined");
 
+  for (int i = 0; i < modify->nfix; i++)
+    if (domain->regions[i]->dynamic)
+      error->all("Cannot use PRD with a time-dependent region defined");
+
   // perform PRD simulation
 
   if (me_universe == 0 && universe->uscreen) 
diff --git a/src/fix_deposit.cpp b/src/fix_deposit.cpp
index 4b446f2da8..b1031a52c8 100644
--- a/src/fix_deposit.cpp
+++ b/src/fix_deposit.cpp
@@ -70,6 +70,8 @@ FixDeposit::FixDeposit(LAMMPS *lmp, int narg, char **arg) :
   if (iregion == -1) error->all("Must specify a region in fix deposit");
   if (domain->regions[iregion]->bboxflag == 0)
     error->all("Fix deposit region does not support a bounding box");
+  if (domain->regions[iregion]->dynamic_check())
+    error->all("Fix deposit region cannot be dynamic");
 
   xlo = domain->regions[iregion]->extent_xlo;
   xhi = domain->regions[iregion]->extent_xhi;
diff --git a/src/fix_wall_region.cpp b/src/fix_wall_region.cpp
index e977d557b9..e90419fa0f 100644
--- a/src/fix_wall_region.cpp
+++ b/src/fix_wall_region.cpp
@@ -62,9 +62,6 @@ FixWallRegion::FixWallRegion(LAMMPS *lmp, int narg, char **arg) :
 
   eflag = 0;
   ewall[0] = ewall[1] = ewall[2] = ewall[3] = 0.0;
-
-  // set this when regions have time dependence
-  // time_depend = 1;
 }
 
 /* ---------------------------------------------------------------------- */
diff --git a/src/region.cpp b/src/region.cpp
index fa1f5a893d..5402f1358c 100644
--- a/src/region.cpp
+++ b/src/region.cpp
@@ -22,7 +22,7 @@
 
 using namespace LAMMPS_NS;
 
-enum{NONE,LINEAR,WIGGLE,ROTATE,VARIABLE};
+enum{NONE,VELOCITY,WIGGLE,ROTATE,VARIABLE};
 
 /* ---------------------------------------------------------------------- */
 
@@ -82,12 +82,12 @@ void Region::options(int narg, char **arg)
       else if (strcmp(arg[iarg+1],"out") == 0) interior = 0;
       else error->all("Illegal region command");
       iarg += 2;
-    } else if (strcmp(arg[iarg],"linear") == 0) {
+    } else if (strcmp(arg[iarg],"vel") == 0) {
       if (iarg+4 > narg) error->all("Illegal region command");
       vx = atof(arg[iarg+1]);
       vy = atof(arg[iarg+2]);
       vz = atof(arg[iarg+3]);
-      dynamic = LINEAR;
+      dynamic = VELOCITY;
       iarg += 4;
     } else if (strcmp(arg[iarg],"wiggle") == 0) {
       if (iarg+5 > narg) error->all("Illegal region command");
@@ -129,7 +129,7 @@ void Region::options(int narg, char **arg)
   }
   else xscale = yscale = zscale = 1.0;
 
-  if (dynamic == LINEAR) {
+  if (dynamic == VELOCITY) {
     vx *= xscale;
     vy *= yscale;
     vz *= zscale;
@@ -160,6 +160,17 @@ void Region::options(int narg, char **arg)
   }
 }
 
+/* ----------------------------------------------------------------------
+   return 1 if region is dynamic, 0 if static
+   only primitive regions define it here
+   union/intersect regions have their own dynamic_check()
+------------------------------------------------------------------------- */
+
+int Region::dynamic_check()
+{
+  return dynamic;
+}
+
 /* ----------------------------------------------------------------------
    determine if point x,y,z is a match to region volume
    XOR computes 0 if 2 args are the same, 1 if different
@@ -174,7 +185,7 @@ int Region::match(double x, double y, double z)
 
   if (dynamic) {
     double delta = (update->ntimestep - time_origin) * dt;
-    if (dynamic == LINEAR) {
+    if (dynamic == VELOCITY) {
       x -= vx*delta;
       y -= vy*delta;
       z -= vz*delta;
@@ -207,7 +218,7 @@ int Region::surface(double x, double y, double z, double cutoff)
 
   if (dynamic) {
     double delta = (update->ntimestep - time_origin) * dt;
-    if (dynamic == LINEAR) {
+    if (dynamic == VELOCITY) {
       x -= vx*delta;
       y -= vy*delta;
       z -= vz*delta;
diff --git a/src/region.h b/src/region.h
index cd796398dc..5e20edaa95 100644
--- a/src/region.h
+++ b/src/region.h
@@ -42,6 +42,7 @@ class Region : protected Pointers {
   Region(class LAMMPS *, int, char **);
   virtual ~Region();
   void init();
+  virtual int dynamic_check();
   int match(double, double, double);
   int surface(double, double, double, double);
 
diff --git a/src/region_intersect.cpp b/src/region_intersect.cpp
index ac773165a9..abb959dea3 100644
--- a/src/region_intersect.cpp
+++ b/src/region_intersect.cpp
@@ -93,6 +93,19 @@ RegIntersect::~RegIntersect()
   delete [] contact;
 }
 
+/* ----------------------------------------------------------------------
+   return 1 if region is dynamic, 0 if static
+   dynamic if any sub-region is dynamic, else static
+------------------------------------------------------------------------- */
+
+int RegIntersect::dynamic_check()
+{
+  Region **regions = domain->regions;
+  for (int ilist = 0; ilist < nregion; ilist++)
+    if (regions[list[ilist]]->dynamic_check()) return 1;
+  return 0;
+}
+
 /* ----------------------------------------------------------------------
    inside = 1 if x,y,z is match() with all sub-regions
    else inside = 0
diff --git a/src/region_intersect.h b/src/region_intersect.h
index 8c09277d57..a14a732a13 100644
--- a/src/region_intersect.h
+++ b/src/region_intersect.h
@@ -22,6 +22,7 @@ class RegIntersect : public Region {
  public:
   RegIntersect(class LAMMPS *, int, char **);
   ~RegIntersect();
+  int dynamic_check();
   int inside(double, double, double);
   int surface_interior(double *, double);
   int surface_exterior(double *, double);
diff --git a/src/region_union.cpp b/src/region_union.cpp
index 89947acab4..90a6815cbf 100644
--- a/src/region_union.cpp
+++ b/src/region_union.cpp
@@ -85,6 +85,19 @@ RegUnion::~RegUnion()
   delete [] contact;
 }
 
+/* ----------------------------------------------------------------------
+   return 1 if region is dynamic, 0 if static
+   dynamic if any sub-region is dynamic, else static
+------------------------------------------------------------------------- */
+
+int RegUnion::dynamic_check()
+{
+  Region **regions = domain->regions;
+  for (int ilist = 0; ilist < nregion; ilist++)
+    if (regions[list[ilist]]->dynamic_check()) return 1;
+  return 0;
+}
+
 /* ----------------------------------------------------------------------
    inside = 1 if x,y,z is match() with any sub-region
    else inside = 0
diff --git a/src/region_union.h b/src/region_union.h
index d73ca85ef1..534d916873 100644
--- a/src/region_union.h
+++ b/src/region_union.h
@@ -22,6 +22,7 @@ class RegUnion : public Region {
  public:
   RegUnion(class LAMMPS *, int, char **);
   ~RegUnion();
+  int dynamic_check();
   int inside(double, double, double);
   int surface_interior(double *, double);
   int surface_exterior(double *, double);