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Power failures and access to PAN:

1. What happens when the power fails?
Answer: There is a crossover switch that will transfer to the alternate 13.8 kV feeder within approximately 100 milliseconds. If you require absolutely continuous power, you must have a UPS on the relevant equipment.

2. Has the crossover switch been tested?
Answer: Yes, and it has also kicked in at least once when the main feed failed.

3. What if the crossover fails? What happens to the electronic locks?
Answer: They operate on batteries for three hours. The understanding is that period will be used to render everything in a safe state.

I was told that at only one time in the last 10 years has a building on campus with a crossover switch lost both circuits. That happened after the 35W bridge collapse, when one of the high voltage feeders was down for several months. There have been other events, such as the ECE flood several years ago that rendered the building's entire power network unusable. See point 8.

4. Has the battery back-up been tested?
Answer: I have no idea.

5. What if the batteries run out?
Answer: The building defaults to locked.

6. What then?
Answer: Take the day off.
Alternative answer: BASC and/or the police/fire department are the only people who can access the outside doors with a key. Keep in mind, however, that if there is no power, the building is considered “unoccupiable.” Make up a good story.

7. If I get into the building but still need to get into a lab or other room which has electronic access, what do I do?
Answer: By this point, you are probably being accompanied by police or fire personnel, who have their own master. Their is one other alternative, which I will write up later. The key ring that has the master key for offices (2CA) also has lab master keys. They are really for an emergency such as water pouring through the ceiling from the lab above.

8. As was already worked out during construction, the building has no emergency power. Make contingency plans if you need them. There are a few locations (the hallway electrical closets plus one or two labs), where there are outlets that go to a breakout box on the loading dock that can be connected to an external generator. These would be used only in the case of a drastic, multi-day power failure.

handbook/door_access.txt · Last modified: 2015/07/12 17:28 by crowell