Confined Space Entry
Confined space entry is controlled access into an enclosed or partially enclosed space with limited entry, potential hazards, and defined permit requirements.
What this term means in maintenance
Confined space entry is controlled access into an enclosed or partially enclosed space with limited entry, potential hazards, and defined permit requirements.
Examples of confined spaces
Examples include:
- Tanks
- Vessels
- Silos
- Pits
- Sewers
- Ducts
- Reactors
- Boilers
- Underground chambers
Hazards
Possible hazards include:
- Oxygen deficiency
- Toxic gas
- Flammable atmosphere
- Engulfment
- Heat
- Mechanical energy
- Restricted rescue
- Chemical residue
Controls
Controls may include isolation, cleaning, gas testing, ventilation, permit, attendant, communication, rescue plan, and entry authorization.
Practical example
A vessel is isolated, cleaned, gas-tested, ventilated, and entered under permit with an attendant and rescue arrangement.
Common mistake
Entering a cleaned vessel without verifying isolation and atmosphere can expose workers to hidden energy and gas hazards.
How this term differs
Confined Space Entry is the controlled entry process for hazardous enclosed spaces. It is related to Permit to Work, Work at Height Permit, and Hot Work Permit, but these terms describe different records, measures, roles, strategies, or decisions and should not be used interchangeably.
Related concepts
Related maintenance terms
Keep exploring connected CMMS, reliability, and maintenance planning terms.
Permit to Work
A permit to work is a formal authorization confirming that defined hazards, isolations, precautions, responsibilities, and validity conditions are controlled before high-risk work begins.
Job Safety Analysis
A Job Safety Analysis is a structured review of work steps, hazards, controls, and responsibilities before a task is performed.
Lockout Tagout
Lockout tagout, or LOTO, is a controlled process used to isolate hazardous energy and prevent unexpected equipment startup or energy release during work.
Glossary FAQs
- What is a confined space?
An enclosed or partly enclosed space with limited entry and potential hazardous conditions.
- What controls are required for Confined Space Entry?
Isolation, cleaning, gas testing, ventilation, permit, attendant, communication, and rescue.
- What are common examples of Confined Space Entry?
Tanks, vessels, silos, pits, ducts, reactors, boilers, and underground chambers.