What simultaneous interpretation costs the interpreter
Simultaneous interpretation is three jobs happening at once: listening to the speaker, converting meaning across the language, and speaking the result — all at conference pace, with a two to three second lag, and no pause button. It is one of the most cognitively demanding tasks in professional work, and it is not sustainable at full accuracy alone.
- Accuracy degrades after roughly 30 minutes of continuous output.
- The failure is silent: a tiring interpreter does not stop, they start dropping detail — a number, a qualifier, a named party.
- In a deposition or an arbitration, that dropped detail lands on the record. In a board session or a congress, it lands in the decision.
What the standard actually requires
This is not an ELAN house rule. ISO 23155, the international standard for conference interpreting, sets the staffing floor for simultaneous work — and the buyers who run events for a living already know it.
- Two interpreters per booth, per language pair.
- Rotation every 20 to 30 minutes, so each interpreter recovers while the other carries the room.
- This applies to simultaneous sessions running beyond about an hour. A short consecutive meeting is a different job and often needs only one interpreter.
2 per booth
Interpreters per language pair — the ISO 23155 standard for simultaneous sessions over an hour.
20 to 30 min
Rotation interval that keeps accuracy high across a full conference day.
1 vendor
Interpreters, booth, headsets, receivers, and technician — one quote, one point of contact.
How to read a quote — and what is missing when it looks cheap
Interpretation is quoted per event, never from a rate card: a one-day English–Spanish negotiation and a three-day multilingual congress are not the same job. The quote drivers are language pair, format, team size, subject matter, duration, and equipment. A serious full-day quote shows all of it — and a cheap one is cheap because something on this list was left out.
- Two interpreters per booth per language pair. One name for a full day is the tell. Ask why.
- The booth or portable system, headsets, and receivers for every listener in the room.
- A technician who sets up and tests before the doors open, not during the first session.
- One vendor accountable for all of it — interpreters, equipment, and the record — so there is a single point of contact when the room is live.
If any of those is absent, you have not been quoted a lower price. You have been quoted a smaller share of the work, and you absorb the rest as risk.
Our court-authorized Peritos Traductores handle depositions, arbitrations, and sworn proceedings where the interpreter must be on the official record, with ATA-certified translators on staff and handling processes aligned with ISO 17100, 18587, and 27001.