Quick and convenient, cash machines are an easy way to withdraw money 24 hours a day, 7 days a week, but these automated machines have become a big target for fraudsters.

In 2009 a total of 36.7 million pounds was stolen through cash machine fraud, and with the devices being used by becoming more sophisticated it is more important than ever to check out an ATM before you put in your card.

So how can you be sure that the cash machine you are using is safe?

Here are the 4 things you need to look out for:

1. Skimmer attachments

One of the major cash machine scams fraudsters currently use involves fitting 'skimmer' devices to cash machines that, once in place, will record your card details.

For this reason, the first thing you should do when you approach a cash machine is check the card slot to check that there is nothing unusual about its appearance.

These 'skimmers' are usually attached over the slot where you enter your card and spray painted to match so it can be hard to spot them.

Check for any scratches, sticky residue, tape or other signs of tamper as well as any part of the machine that looks like it is newer, or made from a different material than the rest. Missing LED lights above the card slot machine is also a giveaway if the ATM you're using usually displays them.

Graham Mott from the cash machine network LINK has some useful advice if you think you have spotted a skimming device: "inform the police or ATM operator immediately ideally using your mobile from in front of the ATM. Warning other people in the queue is helpful as well".

2. Hidden cameras

Another major cash machine scam involves using hidden cameras to capture your card details and most importantly your pin number.

These cameras can be hidden in seemingly inconspicuous places including panels above the cash machine or in fake bank leaflet stands to the side of the machine.

When you approach a cash machine take the time to remove any leaflet containers or anything which could feasibly conceal a hidden camera from near the pin pad and scan around the terminal for any unusual panels.

Be on the lookout for slight variations in colour between panels or small pinholes in line of the pin pad.

If you have any doubts or concerns then report them to your bank immediately and move on to use another machine.

3. Card traps

Card traps work by jamming your debit card in the machine allowing a fraudster to retrieve it at a later date.

Graham Mott from LINK warns: "these are difficult to spot but, if your card is retained by the machine then you should call your bank immediately to put a stop on the card".

Peak times for card trap fraudsters are Friday evenings when lots of people are withdrawing cash and when banks will be closed for a few days - never assume your trapped card is safe over the weekend, call immediately to cancel the card.

4. Suspicious bystanders

While technology has allowed criminals to remotely steal your debit card details many fraudsters still use more low-tech methods of stealing your money. So while not strictly a sign that an ATM has been compromised you need to be extra vigilant if anyone is loitering nearby.

Distraction scams work by drawing your attention while using the cash machine in order to snatch your card or cash without you realising.

A fraudster may 'accidentally' drop something at your feet or bump into you in a seemingly innocent fashion while you are at the ATM terminal and use the distraction to their advantage.

Staying safe

Looking out for the 4 signs above should help you spot anything suspicious before you use a cash machine. However adopting the following will mean your details will be harder to steal if you do miss the signs.

Cover your pin
Making sure you cover your hand while you enter your PIN is a must whenever using a cash machine. If you do this religiously then you can to a large extent nullify the threat posed by hidden cameras and unwanted onlookers.

Remember, as your PIN is only known to you it is essentially the key to your finances. If your card does fall foul of a skimming device fraudsters will find in more difficult to access your accounts without it.

Be wary
If you are suspicious of any cash machine, or the behaviour of anyone near an ATM you should avoid taking any risks.

Try and use the same few cash machines to draw cash, this way you're more likely to spot any fraudulent devices.

If you have a mobile phone contact your bank or the police to report the situation, however do not try and remove any devices or camera's yourself.

Fraudsters will often stay close by while a device is in place to keep an eye on the machine, as hidden cameras and skimming devices can be quite expensive to make. There have been incidents of people who attempt to remove the devices being assaulted by the fraudsters, so rather than put yourself at risk report your suspicions to the authorities.

For more information on how to keep your details safe at the cash machine you can read the Fraud Prevention guide from LINK.