Invitation  to tender No ECHA/2O2O/666 Restricted 3  (s) 3. Contacts  during  the  procurement  procedure. 3.1 Submission  phase (before  the time-limit  for  receipt of tenders) 3.2 Opening of tenders Contacts  between the contracting authority  and tenderers are  prohibited  throughout the procedure  save in  exceptional circumstances  and under the  following  conditions only: Upon request, the  contracting authority may  provide  additional  information  solely for the purpose  of clarifying the  procurement  documents, Any request  for additional information must  be made in writing only  through the above  TED  e- Tendering website in  the  "Questions  & answers"  tab, by clicking  "Create  a  question" (registration on  TED  e-Tendering is required  to be able to create and submit  a  question). The contracting  authority is not bound to reply  to  requests  for additional information received less than  six  workingT  days before the time-limit for  receipt of tenders. The contracting  authority  may,  on its own initiative, inform interested  parties  of any error, inaccuracy,  omission or any other  type of clerical error in the text of the  procurement  documents. Any  additional  information  will  be  published  on the above TED e-Tendering website. The website will be updated regularly  and it is the tenderer’s responsibility  to check for updates and modifications  during the submission  period. Tenders will  be opened in  public  at the  time and  place  indicated under Heading IV.2.7  of the contract notice  (local  time shall be understood as Brussels  time  (UTC+01:00).  A maximum of two  representatives  per  tender may  attend the opening session. For  organisational and security reasons  the tenderer  must  provide  the full name,  date of birth, nationality and ID or  passport number  of the representatives at least  two working days in advance to: procurement@echa.europa.eu.  The  representatives  will  be  required  to  present  the tender reception  confirmation  generated  by e-Submission and  to  sign an  attendance sheet.  The contracting  authority reserves the right to refuse  access to  its  premises  if the above information or  the tender  reception  confirmation  are  not  provided  as required, The  public  part  of the opening session will  be strictly  limited  to the following aspects: verification  that each tender has  been submitted  in  accordance with the submission requirements  of the call for  tender; a announcement  of the tenders  received:  the names  of the tenderers  (all  members in  the $_{case of a }$joint  tender)  will  be announced; a Tenderers  not  present  at the opening session may  send an information request to procurement@echa.europa.eu  if  they  wish  to be  provided  with the information  announced during the  public  opening. Once the  contracting authority has opened  the tender, it shall become its  property  and  will  be treated confidentially. Telakkakatu  6,  P.O. Box 400, FI-00121 Helsinki,  Finland  I  Tel.  +358  $^{9 686180 }$|  Fax +358  $^{9 68618210 }$| echa.europa.eu $^{7 }$Working  days at the contracting authority’s location indicated  under Heading I.1 of the contract notice