Each session will have a chair and an assistant.

The job of the Session Chair is to:

  1. Introduce the speakers
  2. Ensure the sessions run smoothly and in a coordinated manner
    • managing the speaker and audience microphones is the job of the session assistant.
  3. Keep to the schedule
    • In the case of a missing speaker, the session will be suspended, the chair will announce a break and the session will resume at the next scheduled presentation.

The session chair will have an assistant. The job of the assistant is to:

  1. Ensure the countdown clock is running properly.
    • Clock is managed by IMPACT Audio Visual technician.
  2. Ensure the pointer device and remote control for slide advancement is available and in working order.
  3. Ensure a hard copy Bio- profile is available on the stage desk.
  4. Ensure the ‘ask moderator’ is in logged in and on the right session. If it is not, contact Natthawut Suradet.
  5. Assist with attaching the microphone for the next speaker, and
  6. Assist with any general technical issue related to the presentation.

Presentation slides

All slides will be loaded in advance after quality assurance checks by the JACoW team. The IMPACT Audio Visual technician will bring up the correct slides on the presentation laptop. It is not permitted for speakers to use their own laptop, or to load their slides from a thumb drive at the last moment.

Talk timing

Talk durations:

  • Invited: 25 mins + 5 mins for introduction and questions
  • Contributed: 15 mins + 5 mins for introduction and questions

Timers should count down from 25/15 mins with a:

  • yellow warning light at 2-minutes remaining, and
  • red warning light at 0-minutes remaining.

Please keep as close to the published schedule and talk timing as possible. Coordinated sessions will permit conference delegates to move confidently between parallel sessions.

There will be a trained-IPAC staff with a session chair on stage to set up the presentation timers.

NOTE: If a presentation is withdrawn, a presenter does not arrive, or a presentation finishes early, do not bring the next presentation forward. Use the time for questions or a short break. Delegates will be planning to come to presentations based on the published session times.

Speaker introductions

Speakers were requested to provide a short Bio-profile in advance of the conference. These should have been provided to session chairs either by email or as printed copies on the stage.

The objective is to give speakers the maximum time for their presentations. Therefore, introductions by session chairs shall be brief. If the provided biographical sketch is lengthy, then mention the highlights rather than reading the entire sketch verbatim.


Please use the lectern for speaker introduction and your own questions. Speakers should have their microphone attached before the start of their talk. The session assistant will be responsible for this.

Speakers should return their microphone to the sound table or session assistant promptly after their talk is done so it is available for another speaker. Two earpiece mics per room will be provided to be shared between speakers.

There will be two runners in the room equipped with handheld microphones to take questions from the audience.

Ensure that either the chair or presenter always repeats any question that is asked by an audience member without a microphone. 

Question time

Ideally, questions should come from the audience. However, the chair should always be prepared to ask a question or two of each presenter in case no one else does. Prepare questions before hand by reading the abstracts that will be in your session in advance and jot down a couple of questions you could ask each author. Also, try to think of a question or comment that could unify all the papers in the session. This means that you can sit back and enjoy the session more during the actual conference.

Do not ask any questions if the presenter has used all their allocated time. If the chair senses contention or grandstanding in a delegate question to the speaker, intervene and recommend that the parties discuss the point after the session.

Running the Session (Session Chair)

  • Please check the time and place of the session you are chairing on the conference program.
  • Arrive 10 minutes before the start of the session to familiarize yourself and to note if the anticipated speakers are present.
  • Confirm with the assistant that the pointing device is working and the Bio-profile is available.
  • Invite the speakers to sit in the front row to facilitate a quick hand over.
  • At the start of the session, briefly introduce yourself, the session title, and the session duration.
  • Let the audience know that the Conference App has an ‘Ask Moderator’ feature to submit questions for the speaker at the end of the talk. Make it clear that not all questions may be got.
  • A session assistant is required to check that the speaker has a microphone attached and turned on.
  • Introduce the speaker by name and affiliation and then announce the talk title.
  • Give highlights from the speaker’s Bio-profile and invite him/her to start.
  • Position yourself where you can see the speaker and he/she can see you.
  • If the speaker runs over the allotted time (25/15 minutes), consider whether to forego questions or to finish the talk.
    • Example: If the “Conclusions/Summary” slide is up, allow the speaker to finish. If necessary, intervene and use your desk microphone to inform the speaker that his/her time is up. Be courteous but firm.
  • Thank the speaker.
  • Ask the audience if they have any question or comment on the talk (in combination with questions posted through the app) and direct the runners sequentially to those indicating a question by a raised hand.
  • Remain on time and be prepared to close the question period.
  • Thank the speaker.
  • Introduce the next presentation with the title, the presenter name and affiliation, and so on.
  • At the end of the session, remember to thank all the participants and the audience.
  • If there are any housekeeping announcements on behalf of the LOC, this is the time to make them.
  • Finally, formally announce that the session is closed.