OSHA's requirements for confined space entry are designed to protect employees from the hazards associated with entering and working in confined spaces. Here are the key requirements:

1. Permit-Required Confined Spaces: Employers must identify and evaluate confined spaces to determine if they are permit-required. A permit-required confined space has one or more of the following characteristics: contains or has the potential to contain a hazardous atmosphere, contains a material that has the potential for engulfing an entrant, has an internal configuration that could trap or asphyxiate an entrant, or contains any other recognized serious safety or health hazard [1].

2. Entry Permit System: Before entering a permit-required confined space, an entry permit must be completed. This permit should include details such as the purpose of entry, the hazards present, measures taken to isolate the space, acceptable entry conditions, and the rescue and emergency services available [2].

3. Hazard Assessment and Control: Employers must conduct a thorough hazard assessment of the confined space and implement measures to control or eliminate hazards. This includes testing the atmosphere for oxygen content, flammable gases, and toxic substances [3].

4. Training: Employees involved in confined space entry must be trained to understand the hazards, the use of protective equipment, and the procedures for safe entry and exit. Training records must be maintained [3].

5. Rescue and Emergency Services: Employers must have a plan for rescue operations, including the availability of rescue equipment and trained personnel. The plan should ensure that rescue services can be summoned promptly in case of an emergency [2].

6. Communication and Monitoring: Continuous communication must be maintained between the entrant and an attendant outside the space. The atmosphere within the space should be monitored periodically to ensure safety [4].

7. Ventilation: If a hazardous atmosphere is detected, the space must be ventilated to ensure a safe environment before entry. Continuous forced-air ventilation may be used to maintain safe conditions [5].

These requirements are part of OSHA's comprehensive approach to ensuring the safety of workers in confined spaces. Employers must develop and implement a written confined space program that includes these elements and make it available for inspection by employees and their representatives [6].