Remarks on Australian Standard AS1228 (as of 2025)
Historical Development and International Context of the Australian Standard AS 1228
- Origins (1950s–1970s)
Australia began codifying its own regulations for steam boilers and pressure equipment in the 1950s. The early codes were closely modelled on the US ASME Boiler and Pressure Vessel Code, Section I (Power Boilers). The predecessor standard, AS CB1, was virtually identical to ASME I, but adapted to local materials and manufacturing conditions. In 1974, the first independent national standard was published: AS 1228 – ‘Rules for the Design and Construction of Boilers’. - Consolidation and the Influence of ASME (1980s–1990s)
AS 1228 was revised several times during the 1980s. The calculation methodology remained aligned with ASME standards (allowable stress, joint efficiency, test pressure). Material data were based on ASME Section II, supplemented by Australian standards. During this period, Australia also began to take European developments (EN standards) into account. - Alignment with international codes (2000–2010)
The aim of this phase was to harmonise with ISO and EN standards without departing from the ASME framework. Influences: ASME Section I, EN 12952/EN 12953, ISO 16528-1/-2. The result was a hybrid approach: ASME formulas combined with European testing and documentation structures. - Current edition AS 1228:2016
The current version, “AS 1228:2016 – Pressure Equipment – Boilers”, is based on ASME I in terms of calculations, but on ISO 16528 in terms of structure. It incorporates national amendments (AS/NZS 1200, AS 3992, AS 1210). Formulas, safety factors and permissible stresses are virtually identical to those in ASME I. - Conclusion – International Context
AS 1228:2016 is a hybrid standard: mathematically based on ASME, organisationally compatible with ISO/EN, with additional Australian requirements.
Comparison of calculation methods for cylindrical shells (collectors, headers)
| Aspect | AS 1228:2016 | ASME Section I | EN 12952-3:2011 |
| basic formula | t = P·Do / [2·(S·E – 0.6·P)] | t = P·Do / [2·(S·E – 0.6·P)] | t = P·Di / (2·f + P) |
| Material properties | AS/NZS or ASME Section II | ASME Section II Part D | EN 10028, EN 10216 |
| Safety philosophy | |||
| Corrosion inhibitor | t_req = t + c | t_req = t + c | t_req = t + c |
| Weld factor | E (joint efficiency) | E (joint efficiency) | meist E = 1.0 |
| Test pressure | ≥ 1.5 × P | ≥ 1.5 × P | ≥ 1.25 × P |
| Formula origin | taken from ASME Section I | ASME-Original | Membrane stress theory (EN) |
| Validity | t/D < 0.25 | t/D < 0.25 | t/D ≤ 0.1 |
| Remark | almost identical to ASME I | Reference code worldwide | slightly more conservative |
Conclusion: AS 1228:2016 uses mathematical formulas that are virtually identical to those in ASME I, whilst EN 12952-3 is based on a distinct European definition of stress. As a result, given the same material properties, all three codes yield very similar wall thicknesses, with minor deviations due to differences in safety factors and stress definitions.