This is the 10611th most frequent Russian word.
водолазам
"To the divers" (dative plural of "водолаз").
The word "водолазам" indicates the indirect object (dative case) referring to the divers receiving assistance.
Мы отправили помощь водолазам, работающим под водой.
We sent aid to the divers working underwater.
Here, "водолазам" again appears in the dative case, showing that the divers are the recipients of the questions.
Я видел, как водолазам задают вопросы об их работе.
I saw how divers were being asked questions about their work.
In this sentence, "водолазам" expresses the indirect object whom the equipment is beneficial to, following the dative case usage.