The rule is one year, the exceptions are few
Annex-III of the work equipment regulation groups pressure vessels and installations in Table-1. The table has 13 rows; in 10 of them the period is "one year where the standards set no period". The remaining three carry their own rule.
| Equipment | Maximum period | Inspection criteria |
|---|---|---|
| Steam and superheated water boilers | 1 year | TS EN 12952 series, TS EN 12953, TS 497 series |
| Heating boilers (central heating, hot water and similar) | 1 year | TS EN 303 series, TS 497, TS 430, TS EN 12828+A1 |
| Thermal oil boilers | 1 year | DIN 4754-1 |
| Liquefied gas tanks (LPG and similar, underground and above ground) | The period given in the written plan (examination only); reassessment at the end of ten years | TS EN 13445-5, TS 1446, TS EN 12817, TS EN 12819 |
| Compressed air and gas tanks | 1 year | TS 1203 EN 286-1, TS EN 13445-5, TS EN 764-7 |
| Closed expansion tanks | 1 year | TS 10576, TS 1911, TS EN 13831, TS EN 764-7 |
| Calorifiers and accumulation tanks | 1 year | TS 736, TS EN 12897+A1 |
| Dyeing machines (vessels) | 1 year | TS EN ISO 11111-1, TS EN ISO 11111-7, TS EN 764-7 |
| Cryogenic tanks | The periods given in the standards | TS EN ISO 21009-2, TS EN 14197-3 |
| Steam cooking vessels | 1 year | TS 11673 |
| Autoclaves | 1 year | TS EN 285+A1, TS EN 13060+A1 |
| Hazardous liquid storage tanks (dished horizontal or vertical, prismatic, steel or thermoplastic) | 1 year | TS EN 12285-2, TS 8991, TS 712, TS EN 12573 series |
| Atmospheric, vertical, cylindrical, above-ground, welded steel hazardous liquid storage tanks | 10 years | API 620, API 650, API 653, API 2610 |
What the period means
The value in the table is a ceiling. Where the standards set no period, the inspection frequency may not exceed these maximum periods; where a standard does set a period, the standard's period applies. Based on a risk assessment covering ambient conditions, frequency of use, the age of the equipment, maintenance activities, accident or overhaul history and previous inspection results, the frequency of tests and examinations may be increased.
Which standard the inspection follows
As a rule the inspection is carried out against the standard in force in the year the equipment was manufactured. If the equipment can be brought into line with a standard that entered into force later, that newer standard is taken into account as well. If no relevant standard existed at the date of manufacture, the first standard published for that equipment is used.
Report and prohibition of use
The inspection is carried out by an authorised person and the report is kept for as long as the equipment is in use. If the report states a defect compromising safe use, the vessel may not be used until the defect is remedied, and the employer must post a clearly visible warning.
For the other five tables: periodic inspection period table.