OSHA has specific requirements for confined space entry to protect employees from hazards [1]. Here's a breakdown of the key requirements:

1. Evaluation and Identification: Employers must evaluate the workplace to determine if any spaces are permit-required confined spaces [2]. If permit spaces exist, employees must be informed through danger signs or equally effective means [2]. Spaces must be re-evaluated when changes occur that might increase hazards [3].
2. Permit Space Program: If employees will enter permit spaces, a written permit space program must be developed and implemented, and it must be available for inspection by employees and their representatives [2]. The program should include measures to prevent unauthorized entry, identify and evaluate hazards, and develop safe entry procedures [4].
3. Permit System: A system for preparing, issuing, using, and canceling entry permits is required [5]. The entry permit must contain specific information, including the space to be entered, purpose of entry, date and duration, authorized entrants, attendants, entry supervisor, hazards, isolation measures, acceptable entry conditions, test results, rescue services, communication procedures, equipment, and any other necessary information to ensure employee safety [6].
4. Training: Employers must provide training to ensure employees have the understanding, knowledge, and skills for safe performance of their duties [6]. Training must be provided to all new employees, before an employee is assigned permit space duties, before there is a change in assigned duties, when there is a hazard for which the employee hasn't already been trained, or when there is a change in the hazards of an existing confined space [7].
5. Testing and Monitoring: Before entry, the internal atmosphere must be tested for oxygen content, flammable gases and vapors, and potential toxic air contaminants [8]. Continuous monitoring may be required if isolation is infeasible [9]. Testing must be done in this order: oxygen, then combustible gases and vapors, and then for toxic gases and vapors [9].
6. Ventilation: Continuous forced air ventilation must be used to eliminate hazardous atmospheres [8]. The air supply must be from a clean source and not increase hazards [8].
7. Equipment: Employers must provide and maintain necessary equipment at no cost to employees, including testing and monitoring equipment, ventilating equipment, communication equipment, personal protective equipment, lighting, barriers, ladders, and rescue equipment [9].
8. Attendant: At least one attendant must be stationed outside the permit space for the duration of entry operations [5]. The attendant must maintain an accurate count of entrants, communicate with entrants, monitor conditions inside and outside the space, and summon rescue services if needed [10].
9. Entry Supervisor: The entry supervisor is responsible for determining if acceptable entry conditions are present, authorizing entry, overseeing operations, and terminating entry when required [11]. They must verify that all tests have been conducted and procedures and equipment are in place before allowing entry [12].
10. Rescue and Emergency Services: Procedures for summoning rescue and emergency services, rescuing entrants, providing emergency services, and preventing unauthorized personnel from attempting a rescue must be developed and implemented [5]. Rescue services must be evaluated for their ability to respond in a timely manner and their proficiency with rescue-related tasks and equipment [12].
11. Coordination: When multiple employers are involved, entry operations must be coordinated to ensure that employees of one employer do not endanger employees of another [4].

These requirements aim to ensure that confined space entries are performed safely, with proper planning, training, and equipment to protect employees from potential hazards.