(a) It depends on the exact circumstances. There are several issues to deal with here. Firstly, it is clear that the relationship between employer and employee is one in which a duty of care arises, requiring the employer to take reasonable precautions to prevent the worker suffering foreseeable harm.
In Australia, workers' compensation schemes exist to provide compensation to injured workers. Although the sums awarded under the schemes are lower than might be claimed under the common law, the advantage is that the employee does not have to prove that the employer was at fault.
An injured worker could originally choose whether to bring a common law action or make a claim under a workers' compensation scheme. But since the 1980s, the choice has been either removed or limited in some way, for example, by limiting the damages that are recoverable under the common law. This area of law is still in a state of change, with differences of detail between the various jurisdictions.
In the case study, if the common law remains available, A would clearly owe a duty of care in these circumstances to B. The risk of injury to persons working close by collapsing stacks of heavy goods is clearly foreseeable