Hi itbrose
On the assumption that this was an accident at work, but also that the kettle was being used for the usual things that a kettle is used, so perhaps to heat up water in a break out area, then are you sure that you need to do forensic testing?
.....or at the very least there are some easy things you can do before deciding on what forensic testing you might want done and why.
There will be a BS EN that stipulates maximum openings to restrict access to the live components of what is presumably a standard domestic type kettle. That spec will recognise that that conducting materials smaller than human fingers could get into any opening.
So, if the BS EN for machinery safeguarding says (in effect) that the little finger of 95% of the population cannot reach a dangerous part of machinery through a gap of about 6mm, then I would expect that the BS EN for electrical safety on domestic appliances stipulates a smaller maximum opening than 6mm but I don't know what the standard would say.
Assuming that it isn't brand new and has escaped pre Brexit requirements the kettle should have its C E marking - if not then it probably doesn't comply with the BS EN.
If it has CE with no gap then it has been supposedly made to Chinese standards and probably shouldn't be in the UK in the first place - somebody has bought it from a dodgy source!
First thing I would be trying to do is to ask whether there is any evidence of how the kettle came to be in the workplace. With luck it has been bought by the organisation and there is a paper trail showing when it was bought and from where.
Then the paper trail showing when it has been PAT tested.
Then the inspection to check that it has not been obviously damaged before the incident.
I don't know whether you are looking at this from the view of potential claimant or potential defendant but my guess is that if the kettle was designed and manufactured to meet the relevant BS EN and there is nothing to indicate that its level of safety has been compromised then any action is likely to fail if competently defended.
After all the Electricity at Work Regulations 1989 are repeatedly qualified by the words "reasonably practicable" which means that they don't require the risk to be ZERO.
You might find the starting point for a forensic examination here. List of every expert witness claiming expertise in Electrical accident investigation (jspubs.com)
or here....| Expert Witness