HK Confined Space Certified Worker flashcards
HK Confined Space Certified Worker · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Confined space definition
- An enclosed or substantially enclosed place with limited entry and exit, not designed for continuous occupancy, where hazardous atmosphere, engulfment, or other serious risk may exist.
- Competent person
- A person who has the relevant training, experience, and knowledge to assess confined space hazards and certify that entry precautions are adequate.
- Entry certificate
- A document issued by a competent person certifying the space is safe for entry, listing precautions, atmospheric limits, and validity period; displayed at the entrance.
- Permit-to-work
- A formal written authorisation specifying the space, task, hazards, controls, validity period, and signatures of issuer, entrant, and standby person.
- Standby person
- A trained attendant stationed outside the space who maintains headcount, monitors conditions and communications, and summons rescue without entering.
- Oxygen deficiency threshold
- An atmosphere with oxygen below 19.5% by volume is oxygen-deficient and requires supplied-air or SCBA; entry is prohibited without respiratory protection.
- Oxygen enrichment risk
- Oxygen above 23.5% by volume greatly increases fire and combustion risk; entry must not proceed until the atmosphere is corrected.
- %LEL meaning
- Percent of the lower explosive limit; a reading of 10% LEL means the gas concentration is 10% of the level at which it can ignite.
- Test order
- Test oxygen first, then flammable gas, then toxic gases, at multiple depths and points, because gases stratify and oxygen affects combustible readings.
- Bump test
- A functional check of a gas detector using a known test gas before use, confirming sensors and alarms respond correctly.
- H2S exposure limit
- Hydrogen sulphide is a toxic gas with a typical 8-hour TWA of 5 ppm and short-term limit around 10 ppm; it deadens the sense of smell.
- CO exposure limit
- Carbon monoxide is a colourless, odourless toxic gas with a typical 8-hour TWA of 25 ppm; it binds haemoglobin and impairs oxygen transport.
- Engulfment hazard
- Risk of being buried or suffocated by free-flowing solids or liquids (e.g. grain, sludge) in silos, hoppers, or tanks.
- ALARP principle
- Residual risk must be reduced to as low as reasonably practicable before entry is authorised; if controls are inadequate, entry is prohibited.
- Isolation and lockout
- Disconnecting and locking out energy sources and blanking or double-block-and-bleed connected pipes to prevent energy, gas, or liquid entering the space.
- Purging
- Displacing contaminants from a space using air or inert gas; inert gas purging leaves an oxygen-deficient atmosphere requiring SCBA for entry.
- Forced-draft ventilation
- Continuous mechanical blowing of clean air into the space during occupancy, with exhaust discharged safely and no recirculation of exhaust air.
- SCBA use
- Self-contained breathing apparatus supplies breathable air from a cylinder and is required for IDLH, unknown, or oxygen-deficient atmospheres.
- Air-purifying respirator
- A respirator that filters contaminants from ambient air; only used where the atmosphere is known, oxygen-sufficient, and not IDLH.
- Escape set (EEBD)
- Emergency escape breathing device for self-rescue only; it must never be used for entry or rescue operations.
- Fit test
- A test confirming a respirator seals to the wearer's face; wearers must be clean-shaven at the face seal and medically fit.
- Full-body harness
- A harness with attachment points for a lifeline and retrieval system, allowing non-entry rescue and fall protection during confined space work.
- Rescue plan
- A site-specific plan covering rescue equipment, trained rescuers, access routes, and emergency contacts, prepared before any entry.
- Non-entry rescue
- Retrieval of an entrant using a tripod, winch, and harness from outside the space, avoiding the need for rescuers to enter.
- CPR ratio
- For adult resuscitation, deliver 30 chest compressions followed by 2 rescue breaths, and use an AED as soon as available.
- Would-be rescuer fatalities
- Most confined space deaths include untrained rescuers who enter without SCBA; only trained, equipped rescuers may attempt rescue.
- Intrinsically safe tools
- Tools and equipment rated to prevent ignition in flammable atmospheres; internal combustion engines are prohibited inside confined spaces.
- Communication check-in
- Agreed signals and regular check-in intervals between entrants and standby person, tested before entry and logged during work.
- Atmospheric test record
- A record showing instrument ID, calibration date, test points, results, tester name, and time, retained with the permit documentation.
- Permit invalidation
- A permit becomes invalid when conditions change, the shift ends, or the validity period expires; a new permit and re-test are required.
- Headcount log
- A log maintained by the standby person recording names and times of all entrants and exits, used to account for everyone in an emergency.
- Pre-entry briefing
- A documented toolbox talk covering hazards, controls, emergency arrangements, and communication, given to all entrants before work starts.