Manual Shutdown Switch

Q: We got a hit on our life safety inspection because we were told the manual shutdown switch be detached from the generator. The deficiency report says “The manual shutdown switch should be located external to the waterproof enclosure of the generator and should be appropriately identified.” The manual shut off switches of our generators are on the outside of the waterproof enclosure but they are on the outside of the generator but on the side of it. Just getting some clarification before calling an electrician to put a switch away from generator.

A: The surveyor got it right… the manual shut-down switch must not be connected to the generator containment structure. According to section A.5.6.5.6 of NFPA 110-2010, the manual shut-down switch must be mounted exterior of the weatherproof container for the generator. This was discussed in great length at a recent HITF annual meeting and the conclusion was the same; the manual switch must be mounted separate from the container housing the generator.

Temporary Emergency Power Generators

Q: We are going to have temporary generators onsite for two months that we will use during our construction project to replace the main power distribution gear for our bed tower, installing new substation and distribution gear. During the time we will have 10 shutdowns from 4 hours to 12 hours at a time. We will be on the regular emergency power generators and ATS’s normally and only on the temporary units for the shutdowns. This affects normal critical and life safety circuits. Do we have to do monthly generator, and ATS transfers on the temporary units or would the shut downs count for testing? And for annunciation, we are planning to have the generators manned anytime they are in operation with no other temporary remote annunciation. Is this permissible?

A: These are all good questions, and I can provide you with answers on how I would approach this, but ultimately you need to talk with your state, local, and accreditation AHJs in order to get their opinions. Their opinions count and mine does not.

But since you asked, the accreditation organizations already allow an actual emergency event when the generators operate to count as one of the monthly load tests, provided the emergency event meets all of the requirements for a monthly load test. Therefore, I do not see any difference if the temporary generators operate or the regular emergency generators operate during an emergency event. So, I would say you still need to conduct monthly load tests on the generators (normal and temporary units), but an emergency event can count as one of the monthly load tests if it meets all of the requirements for a monthly load test.

I would think an ILSM on the annunciation issue should be sufficient, rather than running a temporary annunciation panel.

Emergency Power Generators

Q: I am a consultant and I visited an ASC that had a natural gas generator housed indoors, located in the basement of the facility. The ATS switch was located in the same room as the generator. I am not used to seeing generators located inside of the building. Is the ATS allowed to be in the same room? Also, there was no emergency battery backup light at the location of the generator and there was no emergency stop button located anywhere in or outside of the facility. Isn’t this required?

A: The fact that the generator is located inside the building may be acceptable, depending when the generator was installed. NFPA 110-2010, section 7.2.1 says the generator shall be installed in a separate room and emergency power supply system equipment shall be permitted to be installed in this room. So, this allows the generator to be installed inside the building in a room, and this allows the ATS to be mounted in the same room.

According to section 7.2.1.1 the room must be separated from the rest of the building by 2-hour fire rated barriers, or the generator may be located outdoors. So, when you see generators mounted inside in a room, check the entrance door (if the door connects the room to the rest of the building) rating as it must be 90-minute fire rated, and the walls must be 2-hour fire rated without any unsealed penetrations.

According to section 7.2.1.2 nothing else, other than what has been described, may be permitted in this room. So the room cannot be used to store ladders, equipment, supplies, etc.

According to section 7.2.3, the room housing the generator must be designed and located to minimize the damage from flooding, caused by fire-fighter flooding; sewer backup; natural disaster. So, locating a generator in a basement does not seem to fit this requirement. This requirement was also found in the 1999 edition of NFPA 110, which was required to be complied with by CMS since March 11, 2003. So, if this generator was installed since March 11, 2003, I would say it is subject to a finding by a surveyor for not locating the generator in an area that would not be affected by flooding.

According to section 7.3.1, the generator equipment location must be provided with a battery-powered emergency lighting. So, if there is no battery powered emergency lighting unit, then that is a potential finding by a surveyor.

According to section 5.6.5.6 the generator must have a remote manual stop station located outside the room that houses the generator, and the remote manual stop station needs to be labeled. So, again, if there is no remote stop switch, then that is another potential finding by a surveyor.