You may purchase the services of additional language expert at a lower price for all your language solutions offered as 2 pairs of humans are better than one where a 100 percent accurate solution is of real concern.
For Translations: Seeing the complexity of the documents and the budget, we tell our clients to go for proofreading services by a second translator. If the budget doesn’t allow, then we closely monitor feedback ratings left on translations by the client, which allow us to implement the changes on the translated file.
For Interpretations: Like Simultaneous Interpretations, since the conversion takes place almost instantaneously the interpreter cannot stop the speech to catch up or to ask questions and need a support of another expert to take over. For this reason simultaneous interpreting is only done in teams of 2 interpreters who take turns every 20-30 minutes.
For Multilingual DTP, Transcription & Other Linguistic Services: A proofreading is definitely recommended by a second linguist with the same reasoning as given for translations.