Question : Problem: How to shut down UPS in event of a fire?

We have a server room that has a Halon fire suppression system and a main power disconnect. If the Halon system triggers, it will trip a relay that shuts down all power to the room. The only problem is that the Uninteruptible Power Supplies will still be supplying power to the servers, which may be on fire. Without shutting down the UPS's, the Halon system may not be able to put out the flames, say coming from a server power supply. That may cause the water sprinklers to need to come on and destroy all the equipment.
My question is, how can the the same relay that triggers the power cutoff switch also shutdown the UPS's? Is this possible? We have a mix of UPS's, some high end and some small rack mount ones. Can they all respond to a relay NO or NC circuit, to power down when the circuit opens or closes? I don't want to use server software because I don't want the UPS's to shutdown unless there is an actual fire, not a power failure.

Answer : Problem: How to shut down UPS in event of a fire?

The only way that you could do this was to have some switch on the ourgoing power circuits of the UPS's, which means a lot of switches and a lot to go wrong. I would look at getting a Online UPS that would be able to support all the servers and when the electrician wires it in, put a switch on the output power side.