Confined Space Entry Permits and Safe Systems of Work

Avoid first, then plan the entry

The starting point under Part 3 of the Safety, Health and Welfare at Work (General Application) Regulations 2007 is that entry into a confined space must be avoided so far as is reasonably practicable. Only when the work genuinely cannot be done from outside should entry be considered — and then it must take place under a safe system of work. If you are unsure whether a space qualifies, start with our overview of confined spaces under Irish law.

What a safe system of work means

A safe system of work is the documented, agreed method for carrying out the task safely. It is built from a thorough risk assessment and sets out every control that must be in place before, during and after entry. For confined spaces, a safe system of work typically addresses:

• The specific task and why entry is necessary.
• The hazards identified and the controls for each.
• Isolation of the space from incoming substances, energy or moving parts.
• Cleaning, purging or ventilating to make the atmosphere safe.
• Atmospheric testing before and during the work.
• The equipment, communication and supervision arrangements.
• The emergency and rescue plan.

The permit-to-work system

A permit-to-work is the formal document that turns the safe system of work into a controlled, signed-off procedure. It is not a permission slip to be rubber-stamped; it is a checklist and a contract that confirms every precaution has been taken before entry begins.

A confined-space entry permit usually records:

• The exact location and a clear description of the work.
• The hazards and the controls applied, including isolations.
• The results of atmospheric testing and the equipment used.
• The names of authorised entrants, the attendant and the supervisor.
• The PPE and rescue equipment required.
• The valid time period — permits are time-limited and must be reviewed if conditions change.
• Sign-off to start work, and sign-back to confirm everyone is out and the space is closed.

A permit-to-work is not paperwork for its own sake. It is the moment someone formally confirms that it is safe to enter — and takes responsibility for that decision.

Atmospheric testing: never assume the air is safe

Because the atmosphere is the leading cause of confined-space deaths, testing the air is one of the most important controls in the permit. The air should be tested before anyone enters, using a calibrated multi-gas detector, and monitored continuously or at intervals while work is under way, because conditions can change rapidly.

Testing should typically check for:

• Oxygen level — neither too low (deficiency) nor unusually high (enrichment, which raises fire risk).
• Flammable gases and vapours — to detect any explosive atmosphere.
• Toxic gases relevant to the space, such as hydrogen sulphide or carbon monoxide.

Detectors must be in date for calibration, used by someone trained in their operation, and the readings recorded on the permit. Testing the atmosphere from outside, before entry, is essential — never lower a person in to "see what it's like".

Supervision and the attendant

No one should ever work alone in a confined space. A trained attendant (sometimes called a top man or stand-by person) stays outside throughout the work, maintaining communication with the entrants, monitoring conditions and ready to raise the alarm. The attendant must never enter the space themselves to attempt a rescue — their role is to summon help and operate any retrieval equipment from outside.

A competent supervisor oversees the operation, checks that the permit conditions are met, authorises entry and ensures the work stops if anything changes. Clear roles and clear communication are what keep the whole system honest.

After the work is done

A confined-space task is not finished when the last person climbs out. The permit must be signed back, confirming all personnel are accounted for, equipment is removed, and the space is sealed or made safe. Any incidents or near misses should be recorded and fed back into the next risk assessment.

Competence is the foundation

Permits and procedures only protect people when everyone involved understands their part. Entrants, attendants and supervisors all need training matched to their role, including atmospheric testing and the rescue plan. Building that competence is the most reliable way to make a safe system of work genuinely safe.