diff --git a/src/core/system_parameters/CMakeLists.txt b/src/core/system_parameters/CMakeLists.txt
index 3e25387ed..a34944710 100644
--- a/src/core/system_parameters/CMakeLists.txt
+++ b/src/core/system_parameters/CMakeLists.txt
@@ -19,6 +19,7 @@ set(SYSTEM_PARAMETERS_SOURCES
     galileo_fnav_message.cc
     galileo_has_data.cc
     galileo_inav_message.cc
+    galileo_ism.cc
     galileo_reduced_ced.cc
     beidou_dnav_navigation_message.cc
     beidou_dnav_ephemeris.cc
@@ -55,6 +56,7 @@ set(SYSTEM_PARAMETERS_HEADERS
     galileo_fnav_message.h
     galileo_has_data.h
     galileo_inav_message.h
+    galileo_ism.h
     galileo_reduced_ced.h
     sbas_ephemeris.h
     gps_cnav_ephemeris.h
@@ -115,6 +117,7 @@ target_link_libraries(core_system_parameters
         Boost::date_time
         Boost::serialization
     PRIVATE
+        Boost::headers
         Gflags::gflags
         Glog::glog
 )
diff --git a/src/core/system_parameters/Galileo_INAV.h b/src/core/system_parameters/Galileo_INAV.h
index 72222baf2..9c9f19315 100644
--- a/src/core/system_parameters/Galileo_INAV.h
+++ b/src/core/system_parameters/Galileo_INAV.h
@@ -274,6 +274,23 @@ constexpr int32_t BITS_IN_OCTET = 8;
 constexpr int32_t FIRST_RS_BIT = 7;
 constexpr int32_t FIRST_RS_BIT_AFTER_IODNAV = 17;
 
+/* Page 22 */
+const std::vector<std::pair<int32_t, int32_t>> ISM_CONSTELLATION_ID_BIT({{7, 3}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_SERVICE_LEVEL_ID_BIT({{10, 3}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_WN_BIT({{13, 12}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_T0_BIT({{25, 9}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_MASK_MSB_BIT({{34, 1}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_MASK_BIT({{35, 32}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_PCONST_BIT({{67, 4}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_PSAT_BIT({{71, 4}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_URA_BIT({{75, 4}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_URE_BIT({{79, 4}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_BNOM_BIT({{83, 4}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_TVALIDITY_BIT({{87, 4}});
+const std::vector<std::pair<int32_t, int32_t>> ISM_CRC_BIT({{97, 32}});
+constexpr int32_t GALILEO_ISM_CRC_DATA_BITS = 96;
+constexpr int32_t GALILEO_ISM_CRC_DATA_BYTES = 12;
+
 /* Page 0 */
 const std::vector<std::pair<int32_t, int32_t>> TIME_0_BIT({{7, 2}});
 const std::vector<std::pair<int32_t, int32_t>> WN_0_BIT({{97, 12}});
diff --git a/src/core/system_parameters/galileo_inav_message.cc b/src/core/system_parameters/galileo_inav_message.cc
index 81c47c3bb..fb28d0adc 100644
--- a/src/core/system_parameters/galileo_inav_message.cc
+++ b/src/core/system_parameters/galileo_inav_message.cc
@@ -1315,6 +1315,40 @@ int32_t Galileo_Inav_Message::page_jk_decoder(const char* data_jk)
                 break;
             }
 
+        case 22:  // Word Type 22: ARAIM Integrity Support Message (ISM)
+            DLOG(INFO) << "Word type 22 arrived";
+            ism_constellation_id = read_octet_unsigned(data_jk_bits, ISM_CONSTELLATION_ID_BIT);
+            ism_service_level_id = read_octet_unsigned(data_jk_bits, ISM_SERVICE_LEVEL_ID_BIT);
+            ism_crc = static_cast<uint32_t>(read_navigation_unsigned(data_jk_bits, ISM_CRC_BIT));
+            gal_ism.set_ism_crc(ism_crc);
+            if (gal_ism.check_ism_crc(data_jk_bits))
+                {
+                    DLOG(INFO) << "I/NAV ARAIM Integrity Support Message CRC OK";
+                    gal_ism.set_ism_constellation_id(ism_constellation_id);
+                    gal_ism.set_ism_service_level_id(ism_service_level_id);
+                    if (ism_constellation_id == 0)
+                        {
+                            DLOG(INFO) << "I/NAV ARAIM Integrity Support Message in Test";
+                        }
+                    if (ism_constellation_id == 1)
+                        {
+                            if (ism_service_level_id == 2)
+                                {
+                                    gal_ism.set_ism_wn(static_cast<uint16_t>(read_navigation_unsigned(data_jk_bits, ISM_WN_BIT)));
+                                    gal_ism.set_ism_t0(static_cast<uint16_t>(read_navigation_unsigned(data_jk_bits, ISM_T0_BIT)));
+                                    gal_ism.set_ism_mask_msb(read_navigation_bool(data_jk_bits, ISM_MASK_MSB_BIT));
+                                    gal_ism.set_ism_mask(static_cast<uint32_t>(read_navigation_unsigned(data_jk_bits, ISM_MASK_BIT)));
+                                    gal_ism.set_ism_pconst(read_octet_unsigned(data_jk_bits, ISM_PCONST_BIT));
+                                    gal_ism.set_ism_psat(read_octet_unsigned(data_jk_bits, ISM_PSAT_BIT));
+                                    gal_ism.set_ism_ura(read_octet_unsigned(data_jk_bits, ISM_URA_BIT));
+                                    gal_ism.set_ism_ure(read_octet_unsigned(data_jk_bits, ISM_URE_BIT));
+                                    gal_ism.set_ism_bnom(read_octet_unsigned(data_jk_bits, ISM_BNOM_BIT));
+                                    gal_ism.set_ism_Tvalidity(read_octet_unsigned(data_jk_bits, ISM_TVALIDITY_BIT));
+                                }
+                        }
+                }
+            break;
+
         case 0:  // Word type 0: I/NAV Spare Word
             Time_0 = static_cast<int32_t>(read_navigation_unsigned(data_jk_bits, TIME_0_BIT));
             DLOG(INFO) << "Time_0= " << Time_0;
@@ -1336,3 +1370,9 @@ int32_t Galileo_Inav_Message::page_jk_decoder(const char* data_jk)
         }
     return page_number;
 }
+
+
+Galileo_ISM Galileo_Inav_Message::get_galileo_ism() const
+{
+    return gal_ism;
+}
\ No newline at end of file
diff --git a/src/core/system_parameters/galileo_inav_message.h b/src/core/system_parameters/galileo_inav_message.h
index 1b37e9083..3acacecdd 100644
--- a/src/core/system_parameters/galileo_inav_message.h
+++ b/src/core/system_parameters/galileo_inav_message.h
@@ -23,6 +23,7 @@
 #include "galileo_almanac_helper.h"
 #include "galileo_ephemeris.h"
 #include "galileo_iono.h"
+#include "galileo_ism.h"
 #include "galileo_utc_model.h"
 #include "gnss_sdr_make_unique.h"  // for std::unique_ptr in C++11
 #include <bitset>
@@ -114,6 +115,8 @@ public:
      */
     Galileo_Ephemeris get_reduced_ced() const;
 
+    Galileo_ISM get_galileo_ism() const;
+
     inline bool get_flag_CRC_test() const
     {
         return flag_CRC_test;
@@ -236,6 +239,7 @@ private:
     std::bitset<GALILEO_DATA_JK_BITS> regenerate_page_3(const std::vector<uint8_t>& decoded) const;
     std::bitset<GALILEO_DATA_JK_BITS> regenerate_page_4(const std::vector<uint8_t>& decoded) const;
 
+    Galileo_ISM gal_ism{};
     std::string page_Even{};
 
     std::vector<uint8_t> rs_buffer;   // Reed-Solomon buffer
@@ -399,6 +403,10 @@ private:
     uint8_t IODnav_LSB19{};
     uint8_t IODnav_LSB20{};
 
+    uint32_t ism_crc{};
+    uint8_t ism_constellation_id{};
+    uint8_t ism_service_level_id{};
+
     bool flag_CRC_test{};
     bool flag_all_ephemeris{};  // Flag indicating that all words containing ephemeris have been received
     bool flag_ephemeris_1{};    // Flag indicating that ephemeris 1/4 (word 1) have been received
diff --git a/src/core/system_parameters/galileo_ism.cc b/src/core/system_parameters/galileo_ism.cc
new file mode 100644
index 000000000..847a4ecd6
--- /dev/null
+++ b/src/core/system_parameters/galileo_ism.cc
@@ -0,0 +1,196 @@
+/*!
+ * \file galileo_ism.cc
+ * \brief Interface of a Galileo Integrity Support Message
+ * \author Carles Fernandez, 2024. cfernandez(at)cttc.cat
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * GNSS-SDR is a Global Navigation Satellite System software-defined receiver.
+ * This file is part of GNSS-SDR.
+ *
+ * Copyright (C) 2010-2024  (see AUTHORS file for a list of contributors)
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * -----------------------------------------------------------------------------
+ */
+
+#include "galileo_ism.h"
+#include <boost/crc.hpp>
+#include <boost/dynamic_bitset.hpp>
+#include <algorithm>
+#include <vector>
+
+void Galileo_ISM::set_ism_constellation_id(uint8_t const_id)
+{
+    this->ism_constellation_id = const_id;
+}
+
+
+void Galileo_ISM::set_ism_service_level_id(uint8_t sl_id)
+{
+    this->ism_service_level_id = sl_id;
+}
+
+
+void Galileo_ISM::set_ism_wn(uint16_t wn_ism)
+{
+    this->ism_wn = wn_ism;
+}
+
+
+void Galileo_ISM::set_ism_t0(uint16_t t0)
+{
+    this->ism_t0 = t0;
+}
+
+
+void Galileo_ISM::set_ism_mask_msb(bool mask_msb)
+{
+    this->ism_mask_msb = mask_msb;
+}
+
+
+void Galileo_ISM::set_ism_mask(uint32_t mask)
+{
+    this->ism_mask = mask;
+}
+
+
+void Galileo_ISM::set_ism_pconst(uint8_t pconst)
+{
+    this->ism_pconst = pconst;
+}
+
+
+void Galileo_ISM::set_ism_psat(uint8_t psat)
+{
+    this->ism_psat = psat;
+}
+
+
+void Galileo_ISM::set_ism_ura(uint8_t ura)
+{
+    this->ism_ura = ura;
+}
+
+
+void Galileo_ISM::set_ism_ure(uint8_t ure)
+{
+    this->ism_ure = ure;
+}
+
+
+void Galileo_ISM::set_ism_bnom(uint8_t bnom)
+{
+    this->ism_bnom = bnom;
+}
+
+
+void Galileo_ISM::set_ism_Tvalidity(uint8_t tvalidity)
+{
+    this->ism_Tvalidity = tvalidity;
+}
+
+
+void Galileo_ISM::set_ism_crc(uint32_t crc)
+{
+    this->ism_crc = crc;
+}
+
+
+uint16_t Galileo_ISM::get_WN_ISM() const
+{
+    return this->ism_wn;
+}
+
+
+uint16_t Galileo_ISM::get_t0_ISM() const
+{
+    return (this->ism_t0 * 1800);
+}
+
+
+double Galileo_ISM::get_pconst_value() const
+{
+    auto it = ISM_PCONST_MAP.find(this->ism_pconst);
+    if (it == ISM_PCONST_MAP.end())
+        {
+            return 0.0;
+        }
+    return it->second;
+}
+
+
+double Galileo_ISM::get_psat_value() const
+{
+    auto it = ISM_PSAT_MAP.find(this->ism_psat);
+    if (it == ISM_PSAT_MAP.end())
+        {
+            return 0.0;
+        }
+    return it->second;
+}
+
+
+float Galileo_ISM::get_ura_m() const
+{
+    auto it = ISM_URA_MAP.find(this->ism_ura);
+    if (it == ISM_URA_MAP.end())
+        {
+            return 0.0;
+        }
+    return it->second;
+}
+
+
+float Galileo_ISM::get_ure_m() const
+{
+    auto it = ISM_URE_MAP.find(this->ism_ure);
+    if (it == ISM_URE_MAP.end())
+        {
+            return 0.0;
+        }
+    return it->second;
+}
+
+
+float Galileo_ISM::get_bnom_m() const
+{
+    auto it = ISM_BNOM_MAP.find(this->ism_bnom);
+    if (it == ISM_BNOM_MAP.end())
+        {
+            return 5.0;  //
+        }
+    return it->second;
+}
+
+
+uint16_t Galileo_ISM::get_Tvalidity_hours() const
+{
+    auto it = ISM_TVALIDITY_MAP.find(this->ism_Tvalidity);
+    if (it == ISM_TVALIDITY_MAP.end())
+        {
+            return 0.0;
+        }
+    return it->second;
+}
+
+
+bool Galileo_ISM::check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits) const
+{
+    boost::dynamic_bitset<unsigned char> frame_bits(bits.to_string().substr(0, GALILEO_ISM_CRC_DATA_BITS));
+
+    std::vector<unsigned char> bytes;
+    boost::to_block_range(frame_bits, std::back_inserter(bytes));
+    std::reverse(bytes.begin(), bytes.end());
+
+    boost::crc_32_type crc32_ism;
+    crc32_ism.process_bytes(bytes.data(), GALILEO_ISM_CRC_DATA_BYTES);
+    const uint32_t crc_computed = crc32_ism.checksum();
+    if (this->ism_crc == crc_computed)
+        {
+            return true;
+        }
+
+    return false;
+}
\ No newline at end of file
diff --git a/src/core/system_parameters/galileo_ism.h b/src/core/system_parameters/galileo_ism.h
new file mode 100644
index 000000000..12436a606
--- /dev/null
+++ b/src/core/system_parameters/galileo_ism.h
@@ -0,0 +1,205 @@
+/*!
+ * \file galileo_ism.h
+ * \brief  Interface of a Galileo Integrity Support Message
+ * \author Carles Fernandez, 2024. cfernandez(at)cttc.es
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * GNSS-SDR is a Global Navigation Satellite System software-defined receiver.
+ * This file is part of GNSS-SDR.
+ *
+ * Copyright (C) 2010-2024  (see AUTHORS file for a list of contributors)
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * -----------------------------------------------------------------------------
+ */
+
+
+#ifndef GNSS_SDR_GALILEO_ISM_H
+#define GNSS_SDR_GALILEO_ISM_H
+
+#include "Galileo_INAV.h"
+#include <bitset>
+#include <cstdint>
+#include <unordered_map>
+
+/** \addtogroup Core
+ * \{ */
+/** \addtogroup System_Parameters
+ * \{ */
+
+
+/*!
+ * \brief This class is a storage for the GALILEO Integrity Support Message as described
+ * in Galileo ICD paragraph 5.2
+ *
+ * See https://www.gsc-europa.eu/sites/default/files/sites/all/files/Galileo_OS_SIS_ICD_v2.1.pdf
+ */
+class Galileo_ISM
+{
+public:
+    /*!
+     * Default constructor
+     */
+    Galileo_ISM() = default;
+
+    void set_ism_constellation_id(uint8_t const_id);
+    void set_ism_service_level_id(uint8_t sl_id);
+    void set_ism_wn(uint16_t wn_ism);
+    void set_ism_t0(uint16_t t0);
+    void set_ism_mask_msb(bool mask_msb);
+    void set_ism_mask(uint32_t mask);
+    void set_ism_pconst(uint8_t pconst);
+    void set_ism_psat(uint8_t psat);
+    void set_ism_ura(uint8_t ura);
+    void set_ism_ure(uint8_t ure);
+    void set_ism_bnom(uint8_t bnom);
+    void set_ism_Tvalidity(uint8_t tvalidity);
+    void set_ism_crc(uint32_t crc);
+
+    bool check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits) const;
+
+    double get_pconst_value() const;
+    double get_psat_value() const;
+    float get_ura_m() const;
+    float get_ure_m() const;
+    float get_bnom_m() const;
+    uint16_t get_WN_ISM() const;
+    uint16_t get_t0_ISM() const;
+    uint16_t get_Tvalidity_hours() const;
+
+private:
+    // ICD 2.1 Table 97
+    std::unordered_map<uint8_t, double> ISM_PCONST_MAP = {
+        {0, 1.0e-8},
+        {1, 1.0e-7},
+        {2, 1.0e-6},
+        {3, 3.0e-6},
+        {4, 6.0e-6},
+        {5, 8.0e-6},
+        {6, 1.0e-5},
+        {7, 2.0e-5},
+        {8, 4.0e-5},
+        {9, 6.0e-5},
+        {10, 8.0e-5},
+        {11, 1.0e-4},
+        {12, 1.25e-4},
+        {13, 1.5e-4},
+        {14, 1.75e-4},
+        {15, 2.0e-4}};
+
+    // ICD 2.1 Table 98
+    std::unordered_map<uint8_t, double> ISM_PSAT_MAP = {
+        {0, 1.0e-7},
+        {1, 3.0e-7},
+        {2, 6.0e-7},
+        {3, 1.0e-6},
+        {4, 2.0e-6},
+        {5, 3.0e-6},
+        {6, 5.0e-6},
+        {7, 7.0e-6},
+        {8, 1.0e-5},
+        {9, 1.2e-5},
+        {10, 1.4e-5},
+        {11, 1.7e-5},
+        {12, 2.05e-5},
+        {13, 2.4e-5},
+        {14, 2.8e-5},
+        {15, 3.0e-5}};
+
+    // ICD 2.1 Table 99
+    std::unordered_map<uint8_t, float> ISM_URA_MAP = {
+        {0, 0.75},
+        {1, 1.0},
+        {2, 1.5},
+        {3, 2.0},
+        {4, 2.25},
+        {5, 2.50},
+        {6, 2.75},
+        {7, 3.0},
+        {8, 3.25},
+        {9, 3.50},
+        {10, 3.75},
+        {11, 4.0},
+        {12, 4.50},
+        {13, 5.0},
+        {14, 5.50},
+        {15, 6.0}};
+
+    // ICD 2.1 Table 100
+    std::unordered_map<uint8_t, float> ISM_URE_MAP = {
+        {0, 0.25},
+        {1, 0.50},
+        {2, 0.75},
+        {3, 1.00},
+        {4, 1.25},
+        {5, 1.50},
+        {6, 1.75},
+        {7, 2.0},
+        {8, 2.25},
+        {9, 2.50},
+        {10, 2.75},
+        {11, 3.0},
+        {12, 3.25},
+        {13, 3.50},
+        {14, 3.75},
+        {15, 4.00}};
+
+
+    // ICD 2.1 Table 101
+    std::unordered_map<uint8_t, float> ISM_BNOM_MAP = {
+        {0, 0.0},
+        {1, 0.10},
+        {2, 0.20},
+        {3, 0.30},
+        {4, 0.40},
+        {5, 0.50},
+        {6, 0.60},
+        {7, 0.75},
+        {8, 0.85},
+        {9, 1.0},
+        {10, 1.20},
+        {11, 1.40},
+        {12, 1.60},
+        {13, 1.80},
+        {14, 2.0},
+        {15, 2.4}};
+
+
+    // ICD 2.1 Table 102
+    std::unordered_map<uint8_t, uint16_t> ISM_TVALIDITY_MAP = {
+        {0, 1},
+        {1, 2},
+        {2, 3},
+        {3, 4},
+        {4, 6},
+        {5, 8},
+        {6, 12},
+        {7, 18},
+        {8, 24},
+        {9, 36},
+        {10, 48},
+        {11, 72},
+        {12, 120},
+        {13, 168},
+        {14, 720},
+        {15, 1440}};
+
+    uint32_t ism_crc{};
+    uint32_t ism_mask{};
+    uint16_t ism_wn{};
+    uint16_t ism_t0{};
+    uint8_t ism_constellation_id{};
+    uint8_t ism_service_level_id{};
+    uint8_t ism_pconst{};
+    uint8_t ism_psat{};
+    uint8_t ism_ura{};
+    uint8_t ism_ure{};
+    uint8_t ism_bnom{};
+    uint8_t ism_Tvalidity{};
+    bool ism_mask_msb{};
+};
+
+/** \} */
+/** \} */
+#endif  // GNSS_SDR_GALILEO_ISM_H
\ No newline at end of file