Solar Panels

[JohnW2]

Many places have a fireman's switch that turns off the supply to things like petrol pumps and illuminated displays. Maybe something similar should be built into solar panels.

Indeed, but it appears that they way they are arranged/wired is not necessarily always 'thought through'. Many moons ago I experienced a situation in which (in response to a very small and very localised fire), firefighters used one of those "fireman's switches" (there were many, 'zoned') in a hospital, and the main effect was to cause a big generator in the basement to automatically fire up and restore some power to the part of the building in question!

Kind Regards, John

 

[bernardgreen]

Hospitals ( and similar places ) are "problematic" when planning for "exceptional" situations. Do you cut the power and plunge a surgical team and the person on the table into darkness when there is a fire on the other side of the building ?

 

[JohnW2]

Hospitals ( and similar places ) are "problematic" when planning for "exceptional" situations. Do you cut the power and plunge a surgical team and the person on the table into darkness when there is a fire on the other side of the building ?

Indeed so, although I think that hospitals etc. are perhaps considered to be more 'unique' (hence singled out for 'special consideration', even if sometimes flawed!) than they necessarily are. Although they don't have operating theatres, intensive care units and 'life support equipment', there are undoubtedly many industrial etc. settings in which sudden total loss of power can be just as great a threat to life and limb.

Kind Regards, John

 

[EddieM]

Same thing would apply to datacenters with beefy diesel backup UPS's

 

[JohnW2]

Same thing would apply to datacenters with beefy diesel backup UPS's

Indeed so - in fact any situation in which there is an automated power back-up system. None of it is any particular problem so long as the control systems involved remain functional and accessible (or, at least, 'contactable - e.g. wirelessly) - but in the absence of that, the automated systems can 'take over'!

Kind Regards, John

 

[ekmdgrf]

You can shutdown nuclear reactors, indeed modern ones have to be "encouraged" to keep going.

One can, provided the control systems are intact. I presume that can get rather more difficult if the control systems have been damaged or destroyed by fire - is there a 'manual' way of doing it.

I believe the last line of defense is a SCRAM, which involves lowing the control rods into the reactor to absorb the neutrons and suppress the chain-reaction. That doesn't really solve the problem of decay heat and most reactors require active cooling to keep the reactor from melting even during shutdown.

I've visited a couple of nuclear power plants. One of them had a huge concrete slab over the top of it. Apparently they had some trouble with steam in the reactor. Ironically, it's widely believed that it was a scram that did for the reactor, the rods pushed steam down into the reactor which displaced the cooling water. Steam being a much less effective neutron absorber than water caused a power excursion, flash boiling a significant amount of the cooling water. Messy.

Windscale is an interesting case. It is/was an air-cooled, graphite moderated reactor. So you have a trio of O2 (air), fuel (graphite) and heat (nuclear decay). Seen that anywhere before? Not a lot that a control rod is going to do for you there.

So in summary, there's plenty that can go wrong. As previously stated, I believe modern reactor designs require active management to keep the chain reaction going and rumor has it that they don't melt down due to decay heat. Nevertheless, I believe they're still to pass the test of time.

 

[stillp]

Hospitals ( and similar places ) are "problematic" when planning for "exceptional" situations. Do you cut the power and plunge a surgical team and the person on the table into darkness when there is a fire on the other side of the building ?

Indeed so, although I think that hospitals etc. are perhaps considered to be more 'unique' (hence singled out for 'special consideration', even if sometimes flawed!) than they necessarily are. Although they don't have operating theatres, intensive care units and 'life support equipment', there are undoubtedly many industrial etc. settings in which sudden total loss of power can be just as great a threat to life and limb.

Kind Regards, John

I was involved in the design of the secure power at a major new hospital a few years ago. The medical team considered that the most critical function for power availability was the pharmacy records. Their argument was that losing the power to an operating theatre will result in a maximum of one death (per theatre), whereas getting the wrong medication could kill most of the patients in the hospital!

 

[JohnW2]

I was involved in the design of the secure power at a major new hospital a few years ago. The medical team considered that the most critical function for power availability was the pharmacy records. Their argument was that losing the power to an operating theatre will result in a maximum of one death (per theatre), whereas getting the wrong medication could kill most of the patients in the hospital!

Good grief! I hope you told them about the merits of having good (ideally real-time) off-site backup of their pharmacy records

You may perhaps also have asked them how losing, or losing access to, the pharmacy records could result in most of the patients getting the wrong medication (which, in any event, would probably kill few, if any, of them, anyway!).

Kind Regards, John

 

[ekmdgrf]

I was involved in the design of the secure power at a major new hospital a few years ago. The medical team considered that the most critical function for power availability was the pharmacy records. Their argument was that losing the power to an operating theatre will result in a maximum of one death (per theatre), whereas getting the wrong medication could kill most of the patients in the hospital!

Good grief! I hope you told them about the merits of having good (ideally real-time) off-site backup of their pharmacy records

You may perhaps also have asked them how losing, or losing access to, the pharmacy records could result in most of the patients getting the wrong medication (which, in any event, would probably kill few, if any, of them, anyway!).

I think possibly the interpretation is that it's not so much giving people the wrong medication, more not being able to give them the medication that they need, as it's not known what they need to be given.

One would hope, of course, that this information is recorded (cached?) on each ward.

 

[stillp]

I did of course question their backup procedure, but as a mere electrical engineer I couldn't understand the complexities of medication management, or so I was told. For example, patients in high-dependency units are given continuous medication by dosing pumps, which are controlled by the central pharmacy computer. By definition, these are very sick people - give them the wrong dose, and they die. Quite quickly in some cases, so off-site backup does not really enable quick enough data recovery. They don't like wards to keep their own records in case they get out of step with the main computer.

 

[ekmdgrf]

I did of course question their backup procedure, but as a mere electrical engineer I couldn't understand the complexities of medication management, or so I was told. For example, patients in high-dependency units are given continuous medication by dosing pumps, which are controlled by the central pharmacy computer. By definition, these are very sick people - give them the wrong dose, and they die. Quite quickly in some cases, so off-site backup does not really enable quick enough data recovery. They don't like wards to keep their own records in case they get out of step with the main computer.

It's possible to design a system for offsite recovery with millisecond failover. I wouldn't want to try though.

So what does a dosing pump do if it loses connection to the main pharmacy computer? Say for example if it does the old "blue screen of death"? Or the link gets hit by the old "fibre-seeking backhoe" or the building it's in gets hit by a giant sperm whale and a bowl of pertunias?

 

[JohnW2]

I did of course question their backup procedure, but as a mere electrical engineer I couldn't understand the complexities of medication management, or so I was told. For example, patients in high-dependency units are given continuous medication by dosing pumps, which are controlled by the central pharmacy computer. By definition, these are very sick people - give them the wrong dose, and they die.

[for a start, you're talking about a tiny minority of patients in a hospital, which rather puts paid to the 'most of the patients would die' idea!] Maybe I'm a bit out-of-touch, but that's all a new one on me, and I find it hard to see how it works. Most patients receiving medication by pump need constant review and alteration of the dosing, based on clinical considerations, which can only be done at the bedside (and often in the middle of the night!) - not a remote pharmacy. Whatever, I find it hard to believe that any such system would exist without there being a facility for direct control at the bedside, should something go wrong in the pharmacy, or with the 'connection to' the pharmacy!

Quite quickly in some cases, so off-site backup does not really enable quick enough data recovery.

How fast can the Internet (let alone direct-cabled connections) transfer data?

They don't like wards to keep their own records in case they get out of step with the main computer.

I must say that I would have doubted that doctors and nurses would be happy (or feel that they were 'safe' from litigation etc.) if they did not have reliable local access to details of their patients' treatment.

Kind Regards, John

 

[ban-all-sheds]

Same thing would apply to datacenters with beefy diesel backup UPS's

I worked somewhere once where the backup diesel generator caused the fire service to turn up.

Power cut.

Generator started up with a very loud bang and a large belch of thick black smoke, and continued to give off a lot of smokey exhaust (I think there must have been something wrong, combustion-wise).

Member of the public reported an explosion and fire.

 

[ban-all-sheds]

Good grief! I hope you told them about the merits of having good (ideally real-time) off-site backup of their pharmacy records

You may perhaps also have asked them how losing, or losing access to, the pharmacy records could result in most of the patients getting the wrong medication (which, in any event, would probably kill few, if any, of them, anyway!).

Pharmacy records. Who needs what pills when.

Perhaps he could have told them about paper and ink.

 

[stillp]

It all seemed a bit far-fetched to me, but I wasn't there to question the hospital's priorities, just to get it built with as much as possible of the spend going to my company. Our profit came from the secure power supplies, what they used it for was up to them.