Final answer:
The employer is responsible for fire detection systems being designed to operate in time to control or extinguish a fire.
Step-by-step explanation:
The person responsible for fire detection systems being designed to operate in time to control or extinguish a fire is the employer. According to the information provided, the employer is obligated to assure that the fire detection systems installed are designed to operate and activate fire extinguishment or suppression systems in a timely manner. This is to ensure that fires can be controlled or extinguished effectively and efficiently.