Is it possible to avoid being sniffed by dogs at Heathrow airport and possibly other airports?

Getting sniffed by a dog is not prohibited in Islam. See this if you want the relevant discussion. In fact, dogs can be kept as pets as long as they are for defence, herding etc. and not as recreational animals.

You may also want to post this separately in islam.stackexchange.com.

Even if you ignore the above - dogs at airports don't sniff people, they sniff luggage and items. This is true for most law enforcement animals (police, immigration, etc.)

Therefore if you are carrying goods on your person, you can place the items on the floor for the inspection; and as mentioned - you can remove items from your pockets and place them in a separate bag.

In my experience travelling across Europe/US/Asia officers at international border control points are trained to be sensitive to various cultural/religious norms. After all, I am sure your family would not be the first Muslim family to come across them during work.

I know that different Muslims interpret the rules around dogs slightly differently, and I am not a scholar of Islam, but there is one piece of pragmatic advice I can contribute here.

I understand that many Muslims believe that if a dog touches your clothes, it is forbidden to pray in those clothes until they have been washed three times. This can be very inconvenient when travelling, especially if you start to run short of clothes.

So I recommend having

• separate clothes for travelling, or for wearing in places where you might encounter a dog;
• separate clothes for praying.

Use plastic bags to keep them separated inside your luggage, so that the najis is not transferred from one set of clothes to the other. Make sure you have one set of "praying clothes" in your carry-on luggage, in case your checked luggage goes missing, or in case you can't get to it when it's time for salah.

You may find this is a problem in places other than airports. Many Europeans take dogs out in public and don't make an effort to keep them away from other people. I've lost count of how many times I've been approached by a dog; and when I back away from it, its owner has told me something like "don't be scared, he won't bite you, he'll probably just lick you to death." So when you go out in public, wear the "travelling" clothes, not the "praying" clothes.

Also, Kate Gregory's advice about talking to your local sheikh or scholar is excellent advice. A properly qualified sheikh will always give you better advice than a bunch of well-meaning strangers on the Internet.

This is a guess rather than something I know, but it may be worth checking if it's possible to request to be searched by means other than a sniffer dog. They may be willing to have a human (or maybe even trained bees) search you instead.