Not only are there the building services that we can all see and feel - like lighting, air conditioning and heating but there are all the technological systems that the medical staff rely on to keep patients alive and well.
It would be easy to take it for granted, but what would happen if the electricity supply failed? It is unthinkable that a building as important as a hospital could be without power for even a second. There are people literally hooked up to machines keeping them alive.
Well, power failures do occur and power cuts are common in countries all over the world. Thankfully, there are systems that kick in in the event of a power cut. Standby power systems and uninterruptible power supplies run by diesel generator sets lie in wait for a problem to occur before whizzing into action. As we walk around the building we would not even know this has happened.
Andy Davies, Managing Director at Excel Power Limited provides sophisticated systems to make sure power is not lost in buildings like hospitals.
"Our job is to supply and install systems that seamlessly integrate into buildings' power supplies that can leap into action without the occupants even realising that the power cut occurred. It's important that we maintain the systems so that they are always in the very best condition. Hopefully, they won't be called upon too often, but when they are, our generators need to be up to the challenge and keeping them well maintained ensures that they will be."
This was the case when an NHS Datacentre recently lost its power supply and its standby power failed. Excel were called in to sort out the problem, fast. They supplied, installed and commissioned a new uninterruptible power supply system the same day which prevented any real problems from happening.
So when it comes to keeping important buildings' heartbeats going, spare a thought for those people whose job it is to maintain them so that those keeping peoples' heartbeats going can do theirs.
Find out more about Excel Power - http://www.excelpowerltd.co.uk