*Everyone* is responsible for being alert to potential problems in the workplace, workers, supervisors, managers, etc.
Host or security staff members
When driving, constantly be alert to potential hazards.
Monitoring will alert you to potential problems that may lead to downtime, or when it comes to security, they can alert you when suspicious activity is occurring on your network.
If you are not alert to the presence of hazards in the workplace, then you are more likely to be impacted by then (i.e to be injured). The idea is that you do not want to be hurt, so you watch out for things or situations that might hurt you.
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An employer should always be alert to anything that might harm the employees, so that they will remain safe and healthy.
Pilots are primarily responsible for collision avoidance in an alert area. They must maintain a good lookout and follow proper traffic patterns and procedures to avoid potential conflicts with other aircraft. Air traffic control may also provide traffic advisories to help pilots avoid collisions.
To make workers aware of the risk, and to keep them alert.
A fault alarm indicates a problem or failure in a system, equipment, or process. It is used to alert operators or users about potential issues that need attention to prevent further problems or downtime. It helps in identifying and resolving problems promptly to ensure smooth operations.
Pain serves to alert a person to potential or actual damage to the body.
Joe notices a person that he's never seen before in the employee lounge area and as far as he can tell the person does not have a badge. Who is responsible to alert and report any suspicious activity or behavior, unsecured portable devices, or unsecured data, or other potential security incidents in accordance with the organization's policies?
Symbols are used in lab procedures and in other kinds of instructions to alert you to important information or to the potential for hazards if procedures are not carefully followed.