Chapter 5. Confined Space Entry

I. Definition of confined space.

A. Confined spaces have few ways in or out, and they may be difficult to get into or out of.

B. They are not intended to be occupied by human beings, at least not on a regular basis.

C. They may contain a hazardous atmosphere or other recognized safety or health hazard.

D. Typical confined spaces:

1. Tanks

2. Diked areas

3. Tunnels

4. Silos

5. Digesters

6. Sewers

7. Storage bins

8. Shafts

9. Hoppers

10. Process vessels

11. Underground utility vaults

12. Cisterns

13. Degreasers

14. Pits

15. Vats

16. Boilers

17. Ducts

18. Manholes

19. Stacks

20. Pipelines

21. Tankcars

22. Septic tanks

23. Steam condensers

24. Trenches

25. Bunkers

26. Pumping or lift stations

27. Equipment housing

II. Entry into confined spaces is not to be taken lightly. Many individuals have died by not taking the proper precautions when entering a tank, vat, silo, pit, or other type of confined area. Precautions must be taken to determine the contents of the space, the adequacy of ventilation for the worker, and adherence to specific good safety practices. Accidents in confined spaces have resulted in severe debilitation and death.

III. All unit heads or directors should identify those areas on site which are confined spaces and train their personnel in proper entry procedures.

IV. Prior to entry into a confined space the following steps should be followed.

A. Train all personnel in the proper procedure for identifying confined spaces and entry into confined spaces.

B. Prior to entry into the confined space test the atmosphere of the confined space. As a minimum the atmosphere should be tested for oxygen (19.5% - 23.5%), the lower explosive limit (LEL), and toxic gases or vapors (carbon monoxide, hydrogen sulfide, or nitric oxide).

C. The director, or the director's designee, must issue an entry permit, which is nothing more than a checklist of procedures that the worker must do prior to entry.

D. There must be a minimum of one attendant stationed outside the confined space to provide emergency backup and rescue. This attendant must maintain communication with the worker and provide continuous monitoring of the confined space for safety.

E. A harness and emergency line should be used to assist in rescue.

F. Mechanical ventilation systems should be used to circulate fresh air throughout the confined space. Respirators may be used if ventilation cannot completely get rid of the hazard or when ventilation is impossible. Each situation will dictate whether air purifying respirators or air supplied respirators are necessary.

G. There should be an individual on the site that can provide emergency first-aid in case of an accident.

H. At no time should individuals enter a confined space to rescue a worker without the necessary personal protective equipment. Remember, 60% of all deaths in confined space are rescuers.