diff --git a/frontend/app/components/btn-select/btn-select.component.html b/frontend/app/components/btn-select/btn-select.component.html
index c852dfbd1..3a47c7e6a 100644
--- a/frontend/app/components/btn-select/btn-select.component.html
+++ b/frontend/app/components/btn-select/btn-select.component.html
@@ -1,6 +1,6 @@
 <mat-form-field class="example-chip-list" appearance="fill">
   <mat-label>{{ titleBtn }}</mat-label>
-  <mat-chip-list #chipList aria-label="option selection">
+  <mat-chip-list #chipList aria-label="option selection" [formControl]="listOpNeeded">
     <mat-chip
       *ngFor="let optionSelected of listOptionChosen"
       [selectable]="selectable"
@@ -28,4 +28,5 @@
       </mat-option>
     </ng-container>
   </mat-autocomplete>
+  <mat-error matErrorMessages></mat-error>
 </mat-form-field>
diff --git a/frontend/app/components/btn-select/btn-select.component.ts b/frontend/app/components/btn-select/btn-select.component.ts
index 195ab17fe..e6df25e6a 100644
--- a/frontend/app/components/btn-select/btn-select.component.ts
+++ b/frontend/app/components/btn-select/btn-select.component.ts
@@ -8,12 +8,13 @@ import {
   Output,
   ViewChild,
 } from '@angular/core';
-import { FormControl } from '@angular/forms';
+import { FormControl, Validators } from '@angular/forms';
 import { MatAutocompleteSelectedEvent } from '@angular/material/autocomplete';
 import { Observable, iif, of } from 'rxjs';
 import { debounceTime, distinctUntilChanged, map, startWith, switchMap } from 'rxjs/operators';
 
 import { JsonData } from '../../types/jsondata';
+import { FormService } from '../../services/form.service';
 
 export interface EmptyObject {
   name: string;
@@ -30,6 +31,7 @@ export class BtnSelectComponent implements OnInit {
   isInit = false;
   separatorKeysCodes: number[] = [ENTER, COMMA];
   myControl = new FormControl();
+  listOpNeeded = new FormControl([],[Validators.required, Validators.minLength(1)])
   @Input() placeholderText: string = 'Selectionnez vos options dans la liste';
   @Input() titleBtn: string = 'Choix des options';
 
@@ -52,9 +54,10 @@ export class BtnSelectComponent implements OnInit {
 
   @Output() public sendobject = new EventEmitter<JsonData>();
 
-  constructor() {}
+  constructor(private _formService: FormService) { }
 
   ngOnInit() {
+
     if(this.isInitialValues && !this.isInit){
       this.initFromExistingObj(this.paramToFilt)
       this.objToEdit.map(val => this.addObject(val))
@@ -73,6 +76,8 @@ export class BtnSelectComponent implements OnInit {
       }),
       map((res) => (res.length > 0 ? res : [{ name: 'Pas de résultats' }]))
     );
+    this.listOpNeeded.setValue(this.listOptionChosen)
+    this._formService.changeExtraFormControl(this.listOpNeeded,"listOptBtnSelect")
   }
 
   remove(option: string): void {
@@ -86,6 +91,8 @@ export class BtnSelectComponent implements OnInit {
       delete this.configObjAdded[option];
     }
     this.sendobject.emit(this.configObjAdded);
+    this.listOpNeeded.setValue(this.listOptionChosen)
+    this._formService.changeExtraFormControl(this.listOpNeeded,"listOptBtnSelect")
   }
 
   selected(event: MatAutocompleteSelectedEvent): void {
@@ -95,6 +102,8 @@ export class BtnSelectComponent implements OnInit {
       : null;
     this.optionInput.nativeElement.value = '';
     this.myControl.setValue(null);
+    this.listOpNeeded.setValue(this.listOptionChosen)
+    this._formService.changeExtraFormControl(this.listOpNeeded,"listOptBtnSelect")
   }
 
   filterOnRequest(val: string, keyToFilt: string): Observable<any> {
diff --git a/frontend/app/components/monitoring-form-g/monitoring-form.component-g.html b/frontend/app/components/monitoring-form-g/monitoring-form.component-g.html
index 7f4f5f46e..27b66a108 100644
--- a/frontend/app/components/monitoring-form-g/monitoring-form.component-g.html
+++ b/frontend/app/components/monitoring-form-g/monitoring-form.component-g.html
@@ -18,7 +18,7 @@ <h2>Attention</h2>
 </pnx-modal-msg>
 
 <div>
-  <div id="properties-form" class="cadre">
+  <div id="properties-form" class="cadre" *ngIf="!hideForm">
     <!-- TODO: voir pour intiialisation si nécessaire à remettre dans la div du dessus -->
     <!-- *ngIf="obj.bIsInitialized && objFormsDefinition" -->
 
diff --git a/frontend/app/components/monitoring-form-g/monitoring-form.component-g.ts b/frontend/app/components/monitoring-form-g/monitoring-form.component-g.ts
index 6ef0d1724..29a8578e9 100644
--- a/frontend/app/components/monitoring-form-g/monitoring-form.component-g.ts
+++ b/frontend/app/components/monitoring-form-g/monitoring-form.component-g.ts
@@ -11,7 +11,7 @@ import { IDataForm } from '../../interfaces/form';
 import { ApiGeomService } from '../../services/api-geom.service';
 import { ConfigJsonService } from '../../services/config-json.service';
 import { FormService } from '../../services/form.service';
-import { ObjectService } from '../../services/object.service';
+import { IExtraForm } from '../../interfaces/object';
 
 @Component({
   selector: 'pnx-monitoring-form-g',
@@ -34,6 +34,10 @@ export class MonitoringFormComponentG implements OnInit {
 
   @Input() sites: {};
   @Input() apiService: ApiGeomService;
+  @Input() isExtraForm:boolean = false;
+
+  extraForm: IExtraForm;
+  hideForm: boolean = false;
   dataForm: IDataForm;
   searchSite = '';
 
@@ -68,11 +72,16 @@ export class MonitoringFormComponentG implements OnInit {
         tap((data) => {
           this.obj = data;
           this.obj.bIsInitialized = true;
-          this.apiService.init(this.obj.endPoint, this.obj.objSelected);
+          this.obj.id = this.obj[this.obj.pk]
         }),
-        mergeMap((data: any) => this._configService.init(data.moduleCode))
+        mergeMap((data: any) => this._configService.init(data.moduleCode)),
+        mergeMap(() => this._formService.currentExtraFormCtrl )
       )
-      .subscribe(() => {
+      .subscribe((frmCtrl) => {
+
+        this.isExtraForm ? this.addExtraFormCtrl(frmCtrl) : null;
+        this.isExtraForm ? this.checkValidExtraFormCtrl() : null;
+
 
         this.queryParams = this._route.snapshot.queryParams || {};
         this.bChainInput = this._configService.frontendParams()['bChainInput'];
@@ -293,7 +302,6 @@ export class MonitoringFormComponentG implements OnInit {
   onSubmit() {
     const { patch_update, ...sendValue } = this.dataForm;
     const objToUpdateOrCreate = this._formService.postData(sendValue, this.obj);
-    console.log(objToUpdateOrCreate);
     const action = this.obj.id
       ? this.apiService.patch(this.obj.id, objToUpdateOrCreate)
       : this.apiService.create(objToUpdateOrCreate);
@@ -381,6 +389,25 @@ export class MonitoringFormComponentG implements OnInit {
     this.procesPatchUpdateForm();
   }
 
+  addExtraFormCtrl(frmCtrl: IExtraForm){
+    if (frmCtrl.frmName in this.objForm.controls){
+      this.objForm.setControl(frmCtrl.frmName,frmCtrl.frmCtrl)
+    } else{
+      this.objForm.addControl(frmCtrl.frmName,frmCtrl.frmCtrl)
+    }
+    
+    this.extraForm = frmCtrl
+  }
+
+  checkValidExtraFormCtrl(){
+    if (this.extraForm.frmName in this.objForm.controls && this.objForm.get(this.extraForm.frmName).value != null && this.objForm.get(this.extraForm.frmName).value.length != 0 ){
+      this.hideForm = false
+      this.objForm.valid
+    } else {
+      this.hideForm = true
+  }
+}
+
   getConfigFromBtnSelect(event) {
     // this.obj.specific == undefined ? (this.obj.specific = {}) : null;
     // TODO: Ajout de tous les id_parents ["id_sites_groups" etc ] dans l'objet obj.dataComplement
diff --git a/frontend/app/components/monitoring-sites-create/monitoring-sites-create.component.html b/frontend/app/components/monitoring-sites-create/monitoring-sites-create.component.html
index cd9a5bcd3..9f1edcf9f 100644
--- a/frontend/app/components/monitoring-sites-create/monitoring-sites-create.component.html
+++ b/frontend/app/components/monitoring-sites-create/monitoring-sites-create.component.html
@@ -8,6 +8,7 @@
 <div>
   <pnx-monitoring-form-g
     [apiService]="siteService"
+    [isExtraForm]="true"
     [objForm]="form"
     #subscritionObjConfig
   ></pnx-monitoring-form-g>
diff --git a/frontend/app/components/monitoring-visits/monitoring-visits.component.html b/frontend/app/components/monitoring-visits/monitoring-visits.component.html
index 704a945a9..db5d49214 100644
--- a/frontend/app/components/monitoring-visits/monitoring-visits.component.html
+++ b/frontend/app/components/monitoring-visits/monitoring-visits.component.html
@@ -20,6 +20,7 @@
   *ngIf="bEdit"
   [(bEdit)]="bEdit"
   [apiService]="siteService"
+  [isExtraForm]="true"
 ></pnx-monitoring-form-g>
 <pnx-monitoring-properties-g
   *ngIf="!bEdit"
diff --git a/frontend/app/components/monitoring-visits/monitoring-visits.component.ts b/frontend/app/components/monitoring-visits/monitoring-visits.component.ts
index 1744aaa98..b6698a02d 100644
--- a/frontend/app/components/monitoring-visits/monitoring-visits.component.ts
+++ b/frontend/app/components/monitoring-visits/monitoring-visits.component.ts
@@ -86,6 +86,7 @@ export class MonitoringVisitsComponent extends MonitoringGeomComponent implement
     .subscribe((data: { site: ISite; visits: IPaginated<IVisit> }) => {
       this._objService.changeSelectedObj(data.site, true);
       this.site = data.site;
+      this.types_site = data.site['types_site']
       this.setVisits(data.visits);
       this.baseFilters = { id_base_site: this.site.id_base_site };
     });
@@ -163,7 +164,8 @@ export class MonitoringVisitsComponent extends MonitoringGeomComponent implement
   }
 
   initValueToSend(){
-    return this.site['types_site']
+    this.initSiteVisit()
+    return this.types_site
   }
 
   updateForm(){
diff --git a/frontend/app/gnModule.module.ts b/frontend/app/gnModule.module.ts
index 0a4d64b09..6391f20ea 100644
--- a/frontend/app/gnModule.module.ts
+++ b/frontend/app/gnModule.module.ts
@@ -55,7 +55,7 @@ import { BtnSelectComponent } from "./components/btn-select/btn-select.component
 import { MonitoringSitesEditComponent } from "./components/monitoring-sites-edit/monitoring-sites-edit.component";
 import { MonitoringVisitsComponent } from "./components/monitoring-visits/monitoring-visits.component";
 import { OptionListButtonComponent } from "./components/option-list-btn/option-list-btn.component";
-
+import { MatErrorMessagesDirective } from './utils/matErrorMessages.directive';
 // my module routing
 const routes: Routes = [
   /** modules  */
@@ -137,6 +137,7 @@ const routes: Routes = [
     BtnSelectComponent,
     MonitoringVisitsComponent,
     OptionListButtonComponent,
+    MatErrorMessagesDirective
   ],
   imports: [
     GN2CommonModule,
diff --git a/frontend/app/interfaces/object.ts b/frontend/app/interfaces/object.ts
index cec2af00d..603c59db8 100644
--- a/frontend/app/interfaces/object.ts
+++ b/frontend/app/interfaces/object.ts
@@ -1,3 +1,4 @@
+import { AbstractControl } from "@angular/forms";
 import { JsonData } from "../types/jsondata";
 import { IPaginated } from "./page";
 import { GeoJSON } from "geojson";
@@ -23,3 +24,5 @@ export type SelectObject = {
   label: string;
 };
 
+
+export type IExtraForm = {frmCtrl :AbstractControl,frmName:string}
diff --git a/frontend/app/services/form.service.ts b/frontend/app/services/form.service.ts
index c8d6b0ff5..0798b10df 100644
--- a/frontend/app/services/form.service.ts
+++ b/frontend/app/services/form.service.ts
@@ -3,23 +3,29 @@ import { BehaviorSubject, Observable, forkJoin, of } from 'rxjs';
 import { concatMap } from 'rxjs/operators';
 
 import { ISite, ISitesGroup } from '../interfaces/geom';
-import { IobjObs, ObjDataType } from '../interfaces/objObs';
 import { JsonData } from '../types/jsondata';
 import { Utils } from '../utils/utils';
 import { MonitoringObjectService } from './monitoring-object.service';
+import { FormControl } from '@angular/forms';
+import { IExtraForm } from '../interfaces/object';
+
 
 @Injectable()
 export class FormService {
   data: JsonData = {};
+  frmCtrl: FormControl = new FormControl(null);
+  frmCtrlName: string = '';
   private dataSub = new BehaviorSubject<object>(this.data);
+  private formCtrl = new BehaviorSubject<IExtraForm>({frmCtrl : this.frmCtrl,frmName:this.frmCtrlName});
   currentData = this.dataSub.asObservable();
+  currentExtraFormCtrl = this.formCtrl.asObservable();
   properties: JsonData = {};
   moduleCode: string;
   objecType: string;
 
   constructor(private _objService: MonitoringObjectService) {}
 
-  // TODO: voir si nécessaire de garder ça (objService permet d'avoir le bon objet ? et sinon modifier pour obtenir ce qu'il faut en formulaire)
+
   changeDataSub(
     newDat: JsonData,
     objectType: string,
@@ -40,6 +46,10 @@ export class FormService {
     this.dataSub.next(newDat);
   }
 
+  changeExtraFormControl(formCtrl:FormControl,formCtrlName:string){
+    this.formCtrl.next({frmCtrl:formCtrl,frmName:formCtrlName})
+  }
+
   formValues(obj): Observable<any> {
     // const {properties ,remainaing} = obj
     const properties = Utils.copy(this.properties);
diff --git a/frontend/app/utils/matErrorMessages.directive.ts b/frontend/app/utils/matErrorMessages.directive.ts
new file mode 100644
index 000000000..66d8b53c8
--- /dev/null
+++ b/frontend/app/utils/matErrorMessages.directive.ts
@@ -0,0 +1,37 @@
+import { Component, AfterViewInit, Injector } from '@angular/core';
+import {MatInput } from '@angular/material/input';
+import { MatFormFieldControl,MatFormField } from '@angular/material/form-field';
+
+@Component({
+  selector: '[matErrorMessages]',
+  template: '{{ error }}'
+})
+export class MatErrorMessagesDirective implements AfterViewInit {
+  error = '';
+  inputRef: MatFormFieldControl<MatInput>;
+
+  constructor(private _inj: Injector) { }
+
+  // Setup all initial tooling
+  ngAfterViewInit() {
+    // grab reference to MatFormField directive, where form control is accessible.
+    let container = this._inj.get(MatFormField);
+    this.inputRef = container._control;
+    
+    // sub to the control's status stream
+    this.inputRef.ngControl.statusChanges.subscribe(this.updateErrors);
+  }
+
+  // This grabs a single active error instead of multiple.
+  private updateErrors = (state: 'VALID' | 'INVALID') => {
+    if (state === 'INVALID') {
+      let controlErrors = this.inputRef.ngControl.errors;
+      const firstError = Object.keys(controlErrors)[0];
+      if(firstError === 'required')
+        this.error = 'Ce champs est requis.';
+
+      if(firstError === 'minlength')
+        this.error = 'Vous devez choisir au moins une valeur.';
+    }
+  }
+}
\ No newline at end of file