Final answer:
The site supervisor is responsible for ensuring that the electrical contractor is performing work safely on the site.
Step-by-step explanation:
The responsibility for ensuring that the electrical contractor is performing work safely on the site lies with the site supervisor. The site supervisor is responsible for overseeing all aspects of the construction project, including monitoring the safety of the workers. They ensure that proper safety protocols are followed and that the work is conducted in accordance with relevant regulations and standards.