diff --git a/backend/project/observations/admin.py b/backend/project/observations/admin.py
index 3014701..9d20b34 100644
--- a/backend/project/observations/admin.py
+++ b/backend/project/observations/admin.py
@@ -1,6 +1,7 @@
 from django.contrib import admin
 from django.contrib.gis.admin import GISModelAdmin
 from django.utils.safestring import mark_safe
+from django.utils.translation import gettext_lazy as _
 from sorl.thumbnail import get_thumbnail
 
 from project.observations.models import (
@@ -18,6 +19,7 @@ class SubTypeInline(admin.TabularInline):
     fields = ("label", "description", "pictogram", "picto_preview")
     readonly_fields = ("picto_preview",)
 
+    @admin.display(description=_("Preview"))
     def picto_preview(self, obj):
         # ex. the name of column is "image"
         if obj.pictogram:
@@ -64,7 +66,33 @@ class ObservationTypeAdmin(admin.ModelAdmin):
     search_fields = ("label", "description")
     ordering = ("label",)
     inlines = [SubTypeInline]
+    readonly_fields = ("picto_preview",)
+    fieldsets = (
+        (
+            None,
+            {
+                "fields": (
+                    (
+                        "label",
+                        "description",
+                    ),
+                )
+            },
+        ),
+        (
+            _("Pictogram"),
+            {
+                "fields": (
+                    (
+                        "picto_preview",
+                        "pictogram",
+                    ),
+                )
+            },
+        ),
+    )
 
+    @admin.display(description=_("Preview"))
     def picto_preview(self, obj):
         # ex. the name of column is "image"
         return mark_safe(
@@ -81,10 +109,11 @@ class ObservationSubTypeAdmin(admin.ModelAdmin):
     list_filter = ("observation_type",)
     ordering = ("label",)
 
+    @admin.display(description=_("Preview"))
     def picto_preview(self, obj):
         # ex. the name of column is "image"
         return mark_safe(
-            '<img src="{0}" width="150" height="150" style="object-fit:contain" />'.format(
+            '<img src="{0}" width="150" height="150" style="object-fit:contain" alt="picto"/>'.format(
                 obj.pictogram.url
             )
         )
diff --git a/backend/project/observations/migrations/0002_alter_observationsubtype_pictogram_and_more.py b/backend/project/observations/migrations/0002_alter_observationsubtype_pictogram_and_more.py
new file mode 100644
index 0000000..3e70bf8
--- /dev/null
+++ b/backend/project/observations/migrations/0002_alter_observationsubtype_pictogram_and_more.py
@@ -0,0 +1,28 @@
+# Generated by Django 5.0.6 on 2024-07-03 15:04
+
+import project.utils.db.fields
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("observations", "0001_initial"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="observationsubtype",
+            name="pictogram",
+            field=project.utils.db.fields.SVGFileField(
+                upload_to="observation_types", verbose_name="Pictogram"
+            ),
+        ),
+        migrations.AlterField(
+            model_name="observationtype",
+            name="pictogram",
+            field=project.utils.db.fields.SVGFileField(
+                upload_to="observation_types", verbose_name="Pictogram"
+            ),
+        ),
+    ]
diff --git a/backend/project/observations/models.py b/backend/project/observations/models.py
index 27d37c9..0e2dfba 100644
--- a/backend/project/observations/models.py
+++ b/backend/project/observations/models.py
@@ -4,6 +4,7 @@
 from django.utils.translation import gettext_lazy as _
 from django.views.generic.dates import timezone_today
 
+from project.utils.db.fields import SVGFileField
 from project.utils.db.mixins import TimeStampMixin
 
 
@@ -23,9 +24,7 @@ class Meta:
 class ObservationType(TimeStampMixin):
     label = models.CharField(max_length=100, unique=True)
     description = models.TextField(blank=True)
-    pictogram = models.ImageField(
-        upload_to="observation_types", verbose_name=_("Pictogram")
-    )
+    pictogram = SVGFileField(upload_to="observation_types", verbose_name=_("Pictogram"))
 
     def __str__(self):
         return self.label
@@ -42,9 +41,7 @@ class ObservationSubType(TimeStampMixin):
     observation_type = models.ForeignKey(
         ObservationType, on_delete=models.PROTECT, related_name="sub_types"
     )
-    pictogram = models.ImageField(
-        upload_to="observation_types", verbose_name=_("Pictogram")
-    )
+    pictogram = SVGFileField(upload_to="observation_types", verbose_name=_("Pictogram"))
 
     def __str__(self):
         return f"{self.label} ({self.observation_type})"
diff --git a/backend/project/utils/db/fields.py b/backend/project/utils/db/fields.py
new file mode 100644
index 0000000..cfe035e
--- /dev/null
+++ b/backend/project/utils/db/fields.py
@@ -0,0 +1,10 @@
+from django.db import models
+
+from project.utils.db.validators import (
+    validate_svg_file_content,
+    validate_svg_file_extension,
+)
+
+
+class SVGFileField(models.FileField):
+    default_validators = [validate_svg_file_extension, validate_svg_file_content]
diff --git a/backend/project/utils/db/validators.py b/backend/project/utils/db/validators.py
new file mode 100644
index 0000000..cd7b420
--- /dev/null
+++ b/backend/project/utils/db/validators.py
@@ -0,0 +1,13 @@
+from django.core.exceptions import ValidationError
+from django.core.validators import FileExtensionValidator
+
+
+def validate_svg_file_extension(value):
+    return FileExtensionValidator(allowed_extensions=["svg"])(value)
+
+
+# write django validator that check if http://www.w3.org/2000/svg is in file content
+def validate_svg_file_content(value):
+    content = str(value.read())
+    if "http://www.w3.org/2000/svg" not in content:
+        raise ValidationError("File is not an SVG file")