1. Maximum concentration of flammable vapor in air above which progagation of flame does not occur on contact with source of ignition.
3. Corrosive, hazardous substances.
5. Closure of a line, duct, or pipe by closing and locking or tagging two in-line valves between two closed valves.
8. If a hazardous atmosphere is detected during an emergency, employees should _______ the space immediately.
9. All lines to a confined space, containing inert, toxic, flammable, or corrosive materials should be valved off and blanked, or disconnected and __________.
12. Type of permit used for a situation that is immediately dangerous to life or health. Situations include but are not limited to oxygen deficiency, explosive or flammable atmospheres, and toxic substances.
14. The action by which a person passes through an opening into a permit-required confined space.
16. Sealed vessel where water is converted to steam.
17. Long cuts made in the ground.
19. No Clue
20. No Clue
23. Protected from heat, cold, noise, etc, by surrounding with material.
25. A cylindrical tower used for storing materials.
27. Large (usually metallic) containers for holding gases or liquids.
28. Boards on which advertisements can be posted outside or near hazardous areas or materials.
29. The minimum concentration of a combustible gas or vapor in air, which will ignite if an ignition source is present.

2. The minimum concentration of a combustible gas or vapor in air, which will ignite if an ignition source is present.
4. Free microscopic particles of solid material.
6. Written document provided by employer to allow and control entry in a permit space.
7. Large open containers for holding or storing liquids.
10. Articles worn for protection from hazardous materials.
11. Equipment (including a retrieval line, chest or full-body harness, wristlets, if appropriate, and a lifting device or anchor) used for non-entry rescue of persons from permit spaces.
13. Maintains an accurate count of authorized entrants in the permit space and also monitors activities inside and outside the confined space.
15. Equipment used in a confined space designed to carry maximum expected load and should be equipped with traction planking.
17. Percent level of chemical substances, biological agents, and physical stresses which cause harmful health effects.
18. No Clue
19. Large open containers used for holding or storing liquids.
21. Material Safety Data Sheet
22. Type of permit that has the potential for causing injury and illness, if preventive measures are not used, but not immediately dangerous to life and health.
24. Containers; usually with lids.
26. Any condition that poses and immediate or delayed threat to life or that would cause irreversible adverse health effects.