Sim cards, voip, and emergency numbers

I'm looking at my options when traveling to Japan.
Essentially, I only need data, *but* I'd like the option to be able to call emergency numbers 110 and 119 if necessary.

As it seems like getting a "voice" sim card in Japan is quite complicated, I was wondering whether I could just get a data sim card, and use a voip provider in the event I need to call an emergency number. Is there a requirement in Japan that when I dial an emergency number via voip, it's routed to the dispatcher?

Otherwise, I've come across the Japan Helpline (http://jhelp.com/en/jhlp.html), which seems to offer 24/7 assistance in English (I don't speak Japanese), and is not a special number, therefore meaning that I can dial it via a Voip provider. Their website is full of dead links and seems out of date, so I'm unsure how reliable they are. Any thoughts?

Finally, as I'll be using an iPhone, would it just work if I dialed an emergency number with a data sim?

Thanks in advance,

PS: I don't really want a pocket modem, as it's something extra to carry around, needs charging...

As it seems like getting a "voice" sim card in Japan is quite complicated

Postpaid voice sims are not available to travelers, but it's not difficult to get a prepaid or rental sim. Just generally more expensive, which tends to drive people to data-only options instead.

to get a re, I was wondering whether I could just get a data sim card, and use a voip provider in the event I need to call an emergency number.

Voip doesn't support emergency services, so its not recommended for that purpose.

Finally, as I'll be using an iPhone, would it just work if I dialed an emergency number with a data sim?

It would work with a voice sim, but I'm not sure data sims support this. Note that you should be able to call emergency services (likely for free) with any voice sim, probably even a sim from home.

Thanks. Which voice/data sims do you recommend?

As long as your phone can switch on and pickup a signal from any service provider, any emergency number will work with or without sim,

adding to my previous post.

I always have a SIM card from my country and have roaming available, if you are not making excessive call, having your phone enable for roaming even though it's may be expensive, at least you have voice call if needed.

So are you saying that even without a voice sim, I could still call emergency numbers if I had a data sim in my iPhone ?

I'm actually thinking of just using a SIM card with a data plan from my country of residence but want to explore all options.

It's a set standard that all emergency numbers like 112, 119, 999 and some others, will work with and without a sim card.

you can even try it now, without a sim, but hang up as soon as the phone starts to ring.

Thanks. I think I'll just use my own SIM card and pay roaming.

you can even try it now, without a sim, but hang up as soon as the phone starts to ring.

Please do not call emergency numbers just to test them out. You may have an officer sent to your door regardless of your hang up.