念(ねん)のため(just) making sure, just to be sure, just in case, for caution's sake

刑事(けいじ)：「念(ねん)のためもう一度(いちど)調(しら)べよう。」

Detective: "Let's check one more time, just to be sure." {(just) making sure, just to be sure, just in case, for caution's sake}

出(で)かける前(まえ)に念(ねん)のため車(くるま)を点検(てんけん)しました。

Just to be sure, I checked the car before going out. {(just) making sure, just to be sure, just in case, for caution's sake}

念(ねん)のため水道(すいどう)業者(ぎょうしゃ)を見直(みなお)したら節約(せつやく)に成功(せいこう)した。

I managed to save money when I reviewed the plumber just to be sure. {(just) making sure, just to be sure, just in case, for caution's sake}

先輩(せんぱい)：「この話(はなし)は大事(だいじ)だから、念(ねん)のためもう一度(いちど)話(はな)すよ。」

Senior: "This matter is important, so I'll talk about it one more time, just to be sure." {(just) making sure, just to be sure, just in case, for caution's sake}

上司(じょうし)：「さっきの話(はなし)の内容(ないよう)を念(ねん)のためメールで送(おく)ってくれない？」

Boss: "Could you send me the contents of our earlier conversation via email, just to be sure?" {(just) making sure, just to be sure, just in case, for caution's sake}