| 1. Hazardous-Area Classification | Confirm whether the tank will be installed in an area containing flammable gas, vapour, mist, or combustible dust. | Area classification according to IEC 60079-10-1 for explosive gas atmospheres or IEC 60079-10-2 for explosive dust atmospheres. | Hazardous-area classification drawing, zoning study, process safety document, and client area schedule. | The project identifies the applicable zone, gas or dust group, temperature class, and equipment protection level before equipment selection. | Mandatory |
| 2. ATEX Applicability to the Tank | Determine whether the water tank is an ATEX product or a non-electrical item installed inside an ATEX zone. | EU Directive 2014/34/EU applies to equipment and protective systems intended for potentially explosive atmospheres. A passive tank is not automatically an ATEX-certified product. | ATEX applicability assessment, equipment boundary document, and written classification decision by the responsible engineering party. | The assessment clearly separates the tank shell from associated instruments, pumps, mixers, valves, heaters, vents, and electrical accessories. | Mandatory |
| 3. Zone and Equipment Category Matching | Check that each ATEX-relevant component has a protection level suitable for the installation zone. | Typical gas-zone relationship: Zone 0 requires Category 1G or EPL Ga; Zone 1 requires Category 1G or 2G or EPL Ga/Gb; Zone 2 requires Category 1G, 2G, or 3G or EPL Ga/Gb/Gc. Dust zones use 1D, 2D, and 3D or EPL Da, Db, and Dc. | Equipment schedule, ATEX marking records, EU-type examination certificates where applicable, and manufacturer declarations. | The selected equipment category or EPL is equal to or higher than the minimum level required by the zone assessment. | Mandatory |
| 4. Equipment Group and Temperature Class | Verify the gas or dust group and maximum surface-temperature limitation for every electrical or mechanical item. | Common gas groups include IIA, IIB, and IIC. Common gas temperature classes are T1 to T6, with T6 having the lowest maximum surface temperature. Dust equipment uses maximum surface temperature and dust-group requirements. | ATEX marking schedule, equipment datasheets, certificate annexes, and hazardous-area equipment register. | The equipment marking is compatible with the identified gas or dust group and does not exceed the process or ignition-temperature limits. | Mandatory |
| 5. Tank Construction and Pressure Boundary | Confirm design pressure, vacuum conditions, operating temperature, material compatibility, corrosion allowance, weld quality, and relief requirements. | For pressure equipment placed on the EU market, Directive 2014/68/EU may apply when the maximum allowable pressure exceeds 0.5 bar. EN 13445 may be used for unfired pressure vessels where specified by the project. | Design calculation, pressure and vacuum rating, material certificates, welding procedure specification, welder qualifications, and inspection plan. | The tank is suitable for the specified operating and design conditions, including filling, draining, thermal expansion, pump-out, and blocked-vent scenarios. | Mandatory |
| 6. Static Electricity and Bonding | Evaluate electrostatic charge generation on the tank, lining, pipework, hoses, filters, and connected equipment. | IEC 60079-0 and IEC TS 60079-32-1 provide relevant principles for electrostatic hazards associated with equipment and installations in explosive atmospheres. | Earthing and bonding drawing, resistance test record, material data for non-metallic parts, and installation inspection checklist. | All conductive parts are bonded and earthed as specified; insulating materials are assessed for charge accumulation and permitted use. | Mandatory where applicable |
| 7. Electrical and Instrumentation Accessories | Check level switches, temperature sensors, pressure transmitters, solenoid valves, junction boxes, cable glands, pumps, motors, and control panels. | IEC 60079 series and the applicable national adoption of ATEX or another accepted conformity system. Associated intrinsically safe circuits must be assessed as a complete system. | Equipment certificates, declarations of conformity, control drawings, intrinsic-safety loop diagrams, cable schedules, and installation manuals. | Every device has traceable marking, an appropriate certificate or declaration, suitable ingress protection, and installation instructions for the designated zone. | Mandatory where applicable |
| 8. Non-Electrical Ignition Sources | Review bearings, rotating agitators, friction points, hot surfaces, mechanical seals, impact points, and possible adiabatic compression. | EN ISO 80079-36 and EN ISO 80079-37 address non-electrical equipment and protection concepts for explosive atmospheres. | Non-electrical ignition-risk assessment, mechanical equipment technical file, temperature assessment, and maintenance instructions. | Potential ignition sources are identified, controlled, and documented; operating limits and maintenance intervals are defined. | Mandatory where applicable |
| 9. Venting, Drainage, and Process Interfaces | Verify vent routing, overflow protection, drain arrangement, flame or pressure protection where required, and separation from incompatible fluids. | Project process design basis, hazardous-area study, applicable pressure-equipment rules, and local fire and environmental requirements. | Piping and instrumentation diagram, line list, vent calculation, relief-device datasheet, drainage plan, and cause-and-effect matrix. | Vents and drains do not create an uncontrolled release or new hazardous zone; discharge locations and isolation arrangements are defined. | Mandatory |
| 10. Certification Route for Global Projects | Identify whether the destination accepts ATEX, IECEx, local certification, or a combination of schemes. | ATEX is an EU legal framework. IECEx is an international conformity-assessment system, but acceptance depends on the destination country and project specifications. | Regulatory compliance matrix, country requirements register, certificate acceptance statement, and client approval record. | The selected certification route is accepted by the authority having jurisdiction, end user, insurer, and procurement specification. | Mandatory |
| 11. Declaration and Marking Review | Check the legal manufacturer information, product designation, applicable directives, standards, certificate number, marking, and year of manufacture. | EU Declaration of Conformity requirements under the applicable EU legislation; ATEX marking must be consistent with the certified equipment configuration. | EU Declaration of Conformity, certificate copy, product label photograph, nameplate drawing, and certificate schedule. | The nameplate and documents identify the same model, protection concept, category, group, temperature class, and permitted conditions of use. | Mandatory where ATEX applies |
| 12. Quality and Manufacturing Records | Confirm traceability of pressure parts, welds, coatings, gaskets, fasteners, and safety-critical components. | Project quality plan, inspection and test plan, specified material standards, and applicable pressure-equipment or fabrication requirements. | Material certificates, weld maps, non-destructive examination reports, dimensional inspection report, coating records, and final release note. | Critical materials and fabrication activities are traceable to the approved drawings, purchase specifications, and inspection points. | Mandatory |
| 13. Factory Acceptance Testing | Verify tank dimensions, nozzles, fittings, instruments, alarms, interlocks, leakage performance, and documentation before shipment. | Approved inspection and test plan and project-specific factory acceptance test procedure. | FAT protocol, signed test results, calibration certificates, punch list, final inspection release, and photographic records. | All specified functional tests pass, deviations are closed or formally accepted, and calibration is valid at the time of testing. | Mandatory |
| 14. Installation and Commissioning | Check foundation, anchoring, pipe stress, earthing, cable glands, equipment orientation, protective devices, and correct installation in the classified area. | IEC 60079-14 for electrical installations in explosive atmospheres, together with local installation and construction requirements. | Installation inspection report, commissioning procedure, electrical continuity test, insulation test, loop-check records, and as-built drawings. | Installation matches certified conditions and approved drawings; all safety-critical tests are completed before energization or operation. | Mandatory where applicable |
| 15. Inspection, Maintenance, and Repair | Define periodic inspection, cleaning, corrosion monitoring, instrument calibration, bonding checks, and repair controls. | IEC 60079-17 for inspection and maintenance of electrical installations in explosive atmospheres; manufacturer instructions and local workplace rules also apply. | Operations and maintenance manual, inspection schedule, spare-parts list, repair procedure, training records, and maintenance log. | Maintenance tasks preserve the certified configuration and include controls against unauthorized component substitution. | Mandatory where applicable |
| 16. Final Project Documentation Package | Ensure the complete technical file is available in the required language and format for approval, operation, and future audits. | Applicable ATEX, pressure-equipment, electrical, workplace-safety, environmental, and local statutory requirements. | Approved drawings, calculations, certificates, declarations, manuals, risk assessments, test records, spare-parts data, and as-built dossier. | No open documentation gaps remain for certification, installation, commissioning, operation, maintenance, or authority inspection. | Mandatory |
