How to limit OpenAI Realtime API sessions to x minutes max?

Hey everyone

I’m using the OpenAI Realtime API to handle live voice and streaming conversations, and I’m generating ephemeral client secrets server-side via POST https://api.openai.com/v1/realtime/sessions.

I know that I can control the token expiration using the expires_in field, but that only limits how long the token can be used to start a connection — it doesn’t actually end an active session once it’s already connected.

What I’m trying to do is: ➡️ Automatically limit each realtime session to 60 minutes max, regardless of whether the client stays connected.

So far, it looks like OpenAI doesn’t expose a server-side parameter for session lifetime after connection.

Has anyone found:

A documented (or undocumented) maximum session duration enforced by OpenAI?

A clean way to force-close a WebRTC / WebSocket session after a set time?

This is both a security and billing concern — since once a client connects, they can theoretically stay connected indefinitely, consuming resources and costs on my side without any enforced timeout.