Here is a great document by NAS on restraint and how it should be used as a last resort:
www.autism.org.uk/~/media/nas/nasschools/helen-allison-school/documents/pdf/nas%20local%20policies/use%20of%20restrictive%20physical%20interventions%20(rpi)%20in%20nas%20schools%20and%20services%20policy%20so-0039.ashx?la=en-gb
However, on some occasions it may be necessary to use as a last resort a strategy that includes a Restrictive Physical Intervention (RPI). Any form of restrictive physical intervention will only be used in order to maintain the welfare and safety of the people we support
and others and should be a method in which staff are trained to achieve this
Restrictive interventions can take several forms and may not always involve direct physical force but also chemical restraint, Pro-re-nata medication (in the form of sedation), rapid tranquilization, mechanical restraint and environmental restraint, such as the holding of doors or blocking egress by use of a person
An RPI is only justified in law if there is the presence of a Clear and Immediate danger. The term ‘immediate’ in this context refers to seconds as opposed to minutes. It does not justify action taken to prevent a possible danger unless incident data clearly shows that a given behaviour or cue quickly results in escalation to a dangerous level, in which case a planned intervention may be justified in the short term, whilst further more positive and proactive strategies are developed
As well as the presence of a clear and immediate danger staff must also be able to demonstrate that all other available less restrictive options have been tried and failed before the use of an RPI. A useful acronym in this situation is ‘TINA’ - There Is No Alternative. The number and nature of the alternatives available to staff will vary but
the use of distractors and motivators (including those staff may feel are in some way ‘rewarding’), removal of triggers, removal of others, change of activity, or change of staff. There is an expectation that alternatives to an RPI would increase with staff training, experience and knowledge of the individual. If you can find no alternative to
using a restrictive physical intervention then you should use it