Hi there
I've been checking this out also, as it's related to my day job. What fun I've had looking into it!
My understanding is the same as Patchouli's - you need only register if you are employed or volunteering with children or vulnerable adults. The scheme has been developed partly in response to the Ian Huntley & Soham case and this is supposed to ensure a more coherent system, so there is no slipping through the net anymore. These checks already happen as part of an enhanced CRB (POVA, POCA and List 99), which again, you would already have if you are employed or volunteering with either of those groups
So if you're self employed or working in a salon, on a day to day basis, it's unlikely that you are in regular contact with children or vulnerable adults, so you wouldn't need to be registered. Even if you did come into contact in this way, in order to have to register, you would need to be in ongoing contact with that group - the terms they use are frequent and intensive.
If you then decided to take your skills somehere like Kids Company, to a mental health group, or local hospice, either as a worker or a volunteer with an ongoing commitment, then you would to register, becuase you are regularly in contact with children and/or vulnerable people. Your registration is for life, so provided you don't do anything that would strike you off, it only ever need be done once, and is free if you're a volunteer.
The information on the ISA website is extremely confusing,and sounds as if they provide advice on the helpline which conflicts with that published on the web. Also, it is very unclear how this system overcomes the issues which occurred in Soham. I do remember it being partly about Ian Huntley having used different surnames (how the ISA scheme prevents this, am not sure ) and about inadequate sharing of information between police forces, again not sure how it addressed this, but hey-ho, just one of the little people, trying to earn a crust!
I think the danger is that, as with CRB's, everyone, everywhere will they think they need to register when it's really about protecting two very specific groups from inappropriate contact & involvement with anyone unsuitable (e.g. anyone convicted of a violent or sexual offence). While I don't particularly like the tone of the legislation or even perhaps the assumptions it makes, we do need a system of safeguards to protect young and vulnerable people. My concern is delays! Dealing with CRB's is enough........
Elodie x