Authorized Gas Tester (AGT) study guide
Authorized Gas Tester (AGT) · Work through your exam, one topic at a time.
The Authorized Gas Tester (AGT) credential is a workplace competency qualification for people who test and certify atmospheres before others enter or work in them. It is typically held by operations and maintenance technicians, confined space entrants and standbys, permit issuers, fire watch and hot work personnel, and contractor supervisors in oil and gas, petrochemicals, utilities, marine, mining and heavy manufacturing. The Authorized Gas Tester (AGT) study guide has 9 sections and about 3,216 words.
01Properties, hazards and behaviour of gases and vapours
This domain tests whether you can predict where a gas will go, how it will hurt you, and what that means for detector placement and test sequence. Vapour density (air = 1): methane 0.55 and hydrogen 0.07 rise and collect at high points; propane 1.5, butane 2.0, H2S 1.19 and CO2 1.53 sink into pits, drains and low areas.
368 words, about 2 min02Legislation, standards, roles and responsibilities
This domain tests the legal basis for gas testing and the boundary between the Authorised Gas Tester (AGT), the permit issuer and the entry supervisor. Health and Safety at Work etc.
383 words, about 2 min03Risk assessment, permits to work and safe systems of work
This domain tests how you build a defensible safe system around a confined space or hot work task, and where gas testing fits. Use remote cameras, sampling lines or external work wherever reasonably practicable.
361 words, about 2 min04Gas detection instruments: principles, selection and limitations
This domain tests how sensors work, which one to choose, and why a reading may be wrong. Catalytic bead (pellistor): measures flammable gas in %LEL by burning it on a heated bead.
359 words, about 2 min05Instrument calibration, bump testing and functional checks
This domain tests the difference between the three checks and the records that prove they happened. Calibration is adjustment of the instrument against a traceable standard gas of known concentration, normally zero and span.
360 words, about 2 min06Pre-entry testing and monitoring of confined spaces
This domain tests the order and technique of testing before entry, and the monitoring that continues during occupancy. Use a pumped instrument and a long probe or sample line; never lean into the space to take a reading.
350 words, about 2 min07Hot work and flammable atmosphere testing
This domain tests the additional controls for welding, cutting, grinding and other ignition sources. Hot work permit is required in hazardous areas and near confined spaces.
371 words, about 2 min08Oxygen deficiency and oxygen enrichment testing
This domain tests the thresholds and the reasons oxygen readings change. Normal air is 20.9% v/v oxygen.
326 words, about 2 min09Record keeping, communication, emergency response and rescue arrangements
This domain tests the paperwork and the human systems that make gas testing effective. The gas test record or certificate should show the date and time, location and level tested, instrument ID, calibration/bump test status, gas and units, reading, permit number, tester's name, conditions and the next re-test time.
338 words, about 2 min