diff --git a/ampel-firmware/csv_writer.cpp b/ampel-firmware/csv_writer.cpp
index 622ea5a0ace2bab758727da7854530da62fedaf0..e5ce6c208e6685ea225728d38a0a9dcaf30e3825 100644
--- a/ampel-firmware/csv_writer.cpp
+++ b/ampel-firmware/csv_writer.cpp
@@ -162,7 +162,7 @@ namespace csv_writer {
 
   void logIfTimeHasCome(const char *timeStamp, const int16_t &co2, const float &temperature, const float &humidity) {
     unsigned long now = seconds();
-    if (now - last_written_at > config::csv_timestep) {
+    if (now - last_written_at > config::csv_interval) {
       last_written_at = now;
       log(timeStamp, co2, temperature, humidity);
     }
@@ -172,9 +172,9 @@ namespace csv_writer {
    * Callbacks for sensor commands                                 *
    *****************************************************************/
   void setCSVinterval(int32_t csv_interval) {
-    config::csv_timestep = csv_interval;
+    config::csv_interval = csv_interval;
     Serial.print(F("Setting CSV Interval to : "));
-    Serial.print(config::csv_timestep);
+    Serial.print(config::csv_interval);
     Serial.println("s.");
     config::save();
     led_effects::showKITTWheel(color::green, 1);
diff --git a/ampel-firmware/mqtt.cpp b/ampel-firmware/mqtt.cpp
index f2cf3ee88acd286748f3e577b012747fe8847398..6e6bbbcf50420dfdca773f5c664cc5555f8b1c58 100644
--- a/ampel-firmware/mqtt.cpp
+++ b/ampel-firmware/mqtt.cpp
@@ -142,17 +142,10 @@ namespace mqtt {
       Serial.println(F(" Connected."));
       last_failed_at = 0;
     } else {
-      char const *mqtt_statuses[] = { // As defined in PubSubClient
-          "Connection timeout", // -4
-              "Connection lost",
-              "Connection failed",
-              "Disconnected",
-              "Connected", // 0
-              "Bad protocol",
-              "Bad client ID",
-              "Unavailable",
-              "Bad credentials",
-              "Unauthorized" }; // 5
+      // As defined in PubSubClient, between -4 and 5
+      const __FlashStringHelper *mqtt_statuses[] = { F("Connection timeout"), F("Connection lost"), F(
+          "Connection failed"), F("Disconnected"), F("Connected"), F("Bad protocol"), F("Bad client ID"), F(
+          "Unavailable"), F("Bad credentials"), F("Unauthorized") };
       last_failed_at = seconds();
       Serial.print(mqtt_statuses[mqttClient.state() + 4]);
       Serial.print("! (Code=");
@@ -166,7 +159,7 @@ namespace mqtt {
   void publishIfTimeHasCome(const char *timestamp, const int16_t &co2, const float &temp, const float &hum) {
     // Send message via MQTT according to sending interval
     unsigned long now = seconds();
-    if (now - last_sent_at > config::mqtt_sending_timestep) {
+    if (now - last_sent_at > config::mqtt_sending_interval) {
       last_sent_at = now;
       publish(timestamp, co2, temp, hum);
     }
@@ -184,9 +177,9 @@ namespace mqtt {
    * Callbacks for sensor commands                                 *
    *****************************************************************/
   void setMQTTinterval(int32_t sending_interval) {
-    config::mqtt_sending_timestep = sending_interval;
+    config::mqtt_sending_interval = sending_interval;
     Serial.print(F("Setting MQTT sending interval to : "));
-    Serial.print(config::mqtt_sending_timestep);
+    Serial.print(config::mqtt_sending_interval);
     Serial.println("s.");
     config::save();
     led_effects::showKITTWheel(color::green, 1);
diff --git a/ampel-firmware/web_config.cpp b/ampel-firmware/web_config.cpp
index fe7221d29053f5a3f0ebd40fe4d04af678d01d1c..f73077afdfa18d0a2c7fd61a860d684e6b4dc484 100644
--- a/ampel-firmware/web_config.cpp
+++ b/ampel-firmware/web_config.cpp
@@ -328,7 +328,7 @@ namespace config {
   bool is_csv_active() {
     return web_config::csvParams.isActive();
   }
-  uint16_t &csv_timestep = web_config::csvTimestepParam.value();
+  uint16_t &csv_interval = web_config::csvTimestepParam.value();
 
   // MQTT
   bool is_mqtt_active() {
@@ -338,7 +338,7 @@ namespace config {
   char *mqtt_user = web_config::mqttUserParam.value();
   char *mqtt_password = web_config::mqttPasswordParam.value();
   uint16_t &mqtt_port = web_config::mqttPortParam.value();
-  uint16_t &mqtt_sending_timestep = web_config::mqttTimestepParam.value();
+  uint16_t &mqtt_sending_interval = web_config::mqttTimestepParam.value();
   bool &mqtt_encryption = web_config::mqttEncryptionParam.value();
   bool &allow_mqtt_commands = web_config::mqttCommandsParam.value();
 
diff --git a/ampel-firmware/web_config.h b/ampel-firmware/web_config.h
index f60ecb0d9c51d8ff2d6746a70ce910757c85a163..a086671872141aa4df32156c5797a14e76630de8 100644
--- a/ampel-firmware/web_config.h
+++ b/ampel-firmware/web_config.h
@@ -36,7 +36,7 @@ namespace config {
 
   //CSV
   bool is_csv_active(); // [true / false]
-  extern uint16_t &csv_timestep; // [s]
+  extern uint16_t &csv_interval; // [s]
 
   // MQTT
   bool is_mqtt_active(); // [true / false]
@@ -44,7 +44,7 @@ namespace config {
   extern char *mqtt_user;
   extern char *mqtt_password;
   extern uint16_t &mqtt_port;
-  extern uint16_t &mqtt_sending_timestep; // [s]
+  extern uint16_t &mqtt_sending_interval; // [s]
   extern bool &mqtt_encryption; // [true / false]
   extern bool &allow_mqtt_commands; // [true / false]
 
diff --git a/ampel-firmware/web_server.cpp b/ampel-firmware/web_server.cpp
index 269042ea0dcf1cc5260d2e28698bef110e74b2a9..8985f5fedb3b3cbcc84f32581ef295b8d669ba8a 100644
--- a/ampel-firmware/web_server.cpp
+++ b/ampel-firmware/web_server.cpp
@@ -208,8 +208,8 @@ namespace web_server {
     // Body
     snprintf_P(content, sizeof(content), body_template, config::ampel_name(), sensor::co2, sensor::temperature,
         sensor::humidity, sensor::timestamp, config::measurement_timestep, csv_writer::last_successful_write,
-        config::csv_timestep, csv_writer::getAvailableSpace() / 1024, mqtt::connected ? "Yes" : "No",
-        mqtt::last_successful_publish, config::mqtt_sending_timestep,
+        config::csv_interval, csv_writer::getAvailableSpace() / 1024, mqtt::connected ? "Yes" : "No",
+        mqtt::last_successful_publish, config::mqtt_sending_interval,
 #if defined(ESP32)
         lorawan::connected ? "Yes" : "No", config::lorawan_frequency_plan, lorawan::last_transmission,
         config::lorawan_sending_interval,