Task $6$: Recognising accident investigation failings

$($a$)$ What should the owner have done to secure the scene immediately after the accident occurred?

Note: Your answer must be based on the scenario only.

$($b$)$ After the contractor has installed the new sign on the exterior wall, the owner arranges to investigate the accident.

How could this delayed action affect the $$gathering information$$ stage of the investigation?

Note: You should support your answer, where applicable, using relevant information from the scenario.

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