diff --git a/tensorflow/lite/micro/tools/ci_build/ci_build_micro_projects.sh b/tensorflow/lite/micro/tools/ci_build/ci_build_micro_projects.sh
index de5b63d964d..96fcc0c90d3 100755
--- a/tensorflow/lite/micro/tools/ci_build/ci_build_micro_projects.sh
+++ b/tensorflow/lite/micro/tools/ci_build/ci_build_micro_projects.sh
@@ -26,7 +26,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 pwd
 
 make -f tensorflow/lite/micro/tools/make/Makefile \
diff --git a/tensorflow/lite/micro/tools/ci_build/test_all.sh b/tensorflow/lite/micro/tools/ci_build/test_all.sh
index 5172f950eac..cdeb30ea215 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_all.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_all.sh
@@ -21,7 +21,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 pwd
 
 make -f tensorflow/lite/micro/tools/make/Makefile \
diff --git a/tensorflow/lite/micro/tools/ci_build/test_arc.sh b/tensorflow/lite/micro/tools/ci_build/test_arc.sh
index 24bbb3e4c63..de8f7c5daea 100644
--- a/tensorflow/lite/micro/tools/ci_build/test_arc.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_arc.sh
@@ -21,7 +21,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 
 source tensorflow/lite/micro/tools/ci_build/helper_functions.sh
 
diff --git a/tensorflow/lite/micro/tools/ci_build/test_arduino.sh b/tensorflow/lite/micro/tools/ci_build/test_arduino.sh
index 996612a977b..ecb821bde63 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_arduino.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_arduino.sh
@@ -21,7 +21,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 
 source tensorflow/lite/micro/tools/ci_build/helper_functions.sh
 
diff --git a/tensorflow/lite/micro/tools/ci_build/test_arduino_library.sh b/tensorflow/lite/micro/tools/ci_build/test_arduino_library.sh
index 087b08d5e01..8770ea96980 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_arduino_library.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_arduino_library.sh
@@ -30,10 +30,10 @@ LIBRARY_ZIP=${1}
 
 rm -rf ${TEMP_BUILD_DIR}
 
-mkdir -p ${ARDUINO_HOME_DIR}/libraries
+mkdir -p "${ARDUINO_HOME_DIR}/libraries"
 mkdir -p ${TEMP_BUILD_DIR}
 
-unzip -q ${LIBRARY_ZIP} -d ${ARDUINO_LIBRARIES_DIR}
+unzip -q ${LIBRARY_ZIP} -d "${ARDUINO_LIBRARIES_DIR}"
 
 # Installs all dependencies for Arduino
 InstallLibraryDependencies () {
@@ -52,7 +52,7 @@ InstallLibraryDependencies () {
   # the defines in ArduCAM/memorysaver.h are correct.
   wget -O /tmp/arducam-master.zip https://github.com/ArduCAM/Arduino/archive/e216049ba304048ec9bb29adfc2cc24c16f589b1/master.zip
   unzip /tmp/arducam-master.zip -d /tmp
-  cp -r /tmp/Arduino-e216049ba304048ec9bb29adfc2cc24c16f589b1/ArduCAM ${ARDUINO_LIBRARIES_DIR}
+  cp -r /tmp/Arduino-e216049ba304048ec9bb29adfc2cc24c16f589b1/ArduCAM "${ARDUINO_LIBRARIES_DIR}"
 }
 
 InstallLibraryDependencies
diff --git a/tensorflow/lite/micro/tools/ci_build/test_bluepill.sh b/tensorflow/lite/micro/tools/ci_build/test_bluepill.sh
index fc0fc18817c..1f957e9dcab 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_bluepill.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_bluepill.sh
@@ -20,7 +20,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 pwd
 
 source tensorflow/lite/micro/tools/ci_build/helper_functions.sh
diff --git a/tensorflow/lite/micro/tools/ci_build/test_mbed.sh b/tensorflow/lite/micro/tools/ci_build/test_mbed.sh
index 894c85ad811..a4d47009c93 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_mbed.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_mbed.sh
@@ -29,7 +29,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 pwd
 
 source tensorflow/lite/micro/tools/ci_build/helper_functions.sh
diff --git a/tensorflow/lite/micro/tools/ci_build/test_mbed_library.sh b/tensorflow/lite/micro/tools/ci_build/test_mbed_library.sh
index 3bf215568b9..c1ec1e60068 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_mbed_library.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_mbed_library.sh
@@ -21,7 +21,7 @@
 set -e
 
 PATH=`pwd`/tensorflow/lite/micro/tools/make/downloads/gcc_embedded/bin:${PATH}
-cd ${1}
+cd "${1}"
 
 mbed config root .
 mbed deploy
diff --git a/tensorflow/lite/micro/tools/ci_build/test_sparkfun.sh b/tensorflow/lite/micro/tools/ci_build/test_sparkfun.sh
index d0130228268..dc08c4e4549 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_sparkfun.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_sparkfun.sh
@@ -20,7 +20,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 
 source tensorflow/lite/micro/tools/ci_build/helper_functions.sh
 
diff --git a/tensorflow/lite/micro/tools/ci_build/test_stm32f4.sh b/tensorflow/lite/micro/tools/ci_build/test_stm32f4.sh
index 14e229c092f..c27817e4a32 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_stm32f4.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_stm32f4.sh
@@ -22,7 +22,7 @@ TARGET=stm32f4
 TAGS=cmsis-nn
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 pwd
 
 source tensorflow/lite/micro/tools/ci_build/helper_functions.sh
diff --git a/tensorflow/lite/micro/tools/ci_build/test_x86.sh b/tensorflow/lite/micro/tools/ci_build/test_x86.sh
index 48ef94aaa21..c150d828164 100755
--- a/tensorflow/lite/micro/tools/ci_build/test_x86.sh
+++ b/tensorflow/lite/micro/tools/ci_build/test_x86.sh
@@ -20,7 +20,7 @@ set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOT_DIR=${SCRIPT_DIR}/../../../../..
-cd ${ROOT_DIR}
+cd "${ROOT_DIR}"
 
 source tensorflow/lite/micro/tools/ci_build/helper_functions.sh