Check out our top five places that your janitorial staff might have missed:

1. Keyboards

It's surprising how much dirt gets under the keyboard of a computer. We hammer away at it day after day, and our hands aren't always going to be squeaky clean. It's worth giving your keyboard a clean to keep dust and bugs at bay - buy some compressed air to squirt under the keys, then mist it with an antibacterial spray (just make sure it isn't plugged in!).

2. Water coolers

Does your cleaner or janitor pull out the water cooler and clean behind it? There's a lot of potential for dirt and bacteria to thrive here as the moisture from the water cooler could make it damp - make sure you use appropriate cleaning products to blitz it every so often.

3. Air conditioning units

It's your company's responsibility to make sure the air-con is serviced and cleaned regularly, because some nasty bugs can thrive in exactly the environment it creates. It's a job for the pros, so make sure to pester someone if you don't see it being serviced for a while.

4. Fridge

We've all had arguments over things being taken from the staff fridge, but people leaving things there can be even worse. Man up and grab that mouldy yoghurt out of the back, then give it a spritz with some kind of antibacterial cleaning product, just to make sure.

5. Stationery cupboards

With people going in and out of the stationery cupboard all day, every day, it's bound to get messy, but that's no excuse for letting it get dirty too. Get stuck in with some furniture polish and banish the dust and dirt to keep your office looking professional and tidy.