Quick answer
The date stamped on the cylinder is not office paperwork. It shows that the receptacle passed a periodic inspection carried out under the transportable pressure equipment regime, and if it has run out, the cylinder may no longer be filled or used in that regime until a new inspection is done.
The applicable act is Directive 2010/35/EU on transportable pressure equipment, read together with Directive 2008/68/EC on the inland transport of dangerous goods. Regulation (EU) 2024/573 does not govern this part: it governs the gas inside the cylinder, not the cylinder as a pressure receptacle. That is why the guides on transporting and returning cylinders point to "other acts" — this is the act.
Two elements are read together on the receptacle: the Pi marking, which attests conformity, and the date of the periodic inspection, accompanied by the identification number of the notified body that carried it out.
It does not contain the periodic inspection intervals. Those are set by ADR for each gas and each type of receptacle, and the authentic ADR text could not be verified from a primary source at the time of writing. An unverifiable figure would be worse than no figure. It also does not contain the exact layout of the stamps on the cylinder shoulder, which is set out in the same annexes.
Which law applies, and where the interval comes from
Directive 2010/35/EU sets out detailed rules for transportable pressure equipment in order to enhance safety and ensure free movement of such equipment within the Union (Article 1(1)).
The definition in Article 2, point (1), covers all pressure receptacles, their valves and other accessories as covered in Chapter 6.2 of the Annexes to Directive 2008/68/EC, when used for the transport of Class 2 gases, as well as tanks and similar equipment from Chapter 6.8. Your refrigerant cylinder sits here.
Article 1(2) marks out three situations: new equipment for the purpose of making it available on the market; existing equipment bearing the conformity markings for the purposes of its periodic inspections, intermediate inspections, exceptional checks and use; and equipment without the marking, for the purposes of reassessment of conformity.
Article 2, point (18), defines periodic inspection as the periodic inspection and the procedures governing it as set out in the Annexes to Directive 2008/68/EC. Annex I, Section I.1, to that directive makes Annexes A and B to ADR applicable inside the Union. The actual interval is therefore not in the transportable pressure equipment directive but in that text, differentiated by gas and by type of receptacle. Take it from there or from the owner of the cylinder, not from a summary.
Article 3 adds a useful nuance: Member States may establish on their territory on-site requirements for the mid- or long-term storage or the on-site use of transportable pressure equipment, but they shall not establish additional requirements for the equipment itself. In other words, national storage rules may sit on top of what is described here. See also the guide on storing cylinders.
The Pi marking and the inspection date
Article 2, point (16), defines the Pi marking as a marking which indicates that the transportable pressure equipment is in conformity with the applicable conformity assessment requirements set out in the Annexes to Directive 2008/68/EC and in the directive itself.
The rules for affixing it are in Articles 14 and 15:
- Article 14(1) — the Pi marking shall only be affixed by the manufacturer or, in cases of reassessment of conformity, as set out in Annex III. For gas cylinders previously in compliance with the older directives, it is affixed by or under the surveillance of the notified body.
- Article 14(4) — the Pi marking is the only marking which attests conformity of the equipment with the applicable requirements.
- Article 14(5) — the affixing of markings, signs and inscriptions which are likely to mislead third parties as to the meaning or form of the Pi marking is prohibited; any other marking shall be affixed so that the visibility, legibility and meaning of the Pi marking are not impaired.
- Article 15(2) — the minimum height of the Pi marking is 5 mm; for equipment with a diameter of 140 mm or less, the minimum is 2,5 mm.
- Article 15(4) — the marking shall be affixed visibly, legibly and permanently to the equipment or to its data plate, as well as to demountable parts of refillable equipment having a direct safety function.
- Article 15(6) — the Pi marking shall be followed by the identification number of the notified body involved in the initial inspections and tests.
The marking of the date of the periodic inspection or, where appropriate, the intermediate inspection shall be accompanied by the identification number of the notified body responsible for the periodic inspection.
That is the check you can do at goods-in with no instrument at all: if a date of inspection appears on the cylinder, a notified body number has to appear next to it. A bare date with no body number does not match the wording of the directive.
Article 15(8) covers the transition: for gas cylinders previously in compliance with Directives 84/525/EEC, 84/526/EEC or 84/527/EEC that do not bear the Pi marking, when the first periodic inspection under the current directive is carried out, the identification number of the responsible notified body shall be preceded by the Pi marking.
What you actually read on the cylinder
The permanent markings sit on the thick part of the receptacle: on the shoulder, on the neck ring, or on a data plate, as Article 15(4) allows. They are stamped, not printed, and they are not to be confused with the product label, which is an entirely different document.
- The Pi marking, followed by the number of the notified body involved in the initial inspections and tests (Article 15(6)).
- The date of the last periodic inspection, accompanied by the number of the notified body responsible for that inspection (Article 15(7)).
- The manufacturing markings of the receptacle, identifying the manufacturer and the receptacle. The exact form of those stamps is set out in the Annexes to Directive 2008/68/EC and is not reproduced here.
A marking covered by paint, rust or a stuck-on label is not a legible marking. Do not clean it aggressively and do not try to restore it yourself: Article 14(1) says who may affix the Pi marking, and Article 14(5) prohibits markings that may mislead. Photograph what is visible and ask the cylinder owner or the filler to clarify.
The product label has its own, separate requirements: Article 12(4) of Regulation (EU) 2024/573 requires it to be clearly legible and indelible, and Article 1(2) of Implementing Regulation (EU) 2024/2174 requires it to remain securely in place and legible throughout the entire period during which the product contains the gas. The stamped markings and the label answer different questions and both have to be right. See the guide on documents with a refrigerant cylinder.
Who is answerable for what
Directive 2010/35/EU distributes the duties by role, and the roles are defined in Article 2. Two definitions matter directly for a refrigerant cylinder:
- Use, Article 2, point (5) — filling, temporary storage linked to carriage, emptying and refilling of transportable pressure equipment. So "use" includes filling, not only consuming the gas.
- Owner and operator, points (12) and (13) — the natural or legal person established in the Union who owns the equipment, and the one who uses it.
The duties that matter at goods-in and in use:
| Role | Duty | Basis |
|---|---|---|
| Manufacturer | Design, manufacture and documentation in conformity; affixing the Pi marking | Article 4(1) and (2) |
| Importer | Place on the market only conforming equipment; check the Pi marking and the certificate of conformity | Article 6(1) and (2) |
| Distributor | Before making available, verify the Pi marking, the certificate of conformity and the contact address | Article 7(1) |
| Owner | Shall not make available or use equipment that is not in conformity, including the requirements for periodic inspection | Article 8(1) |
| Operator | Shall use only conforming equipment; shall inform the owner and the market surveillance authorities where the equipment presents a risk | Article 9(1) and (2) |
Where an owner considers or has reason to believe that transportable pressure equipment is not in conformity with the Annexes to Directive 2008/68/EC, including the requirements for periodic inspection, and with this Directive, he shall not make it available or use it until it has been brought into conformity. Owners shall document all such instances of non-compliance and corrective measures.
That wording is what turns an expired date from an administrative matter into a prohibition on use. And because "use" includes filling, a cylinder with an expired inspection is not filled.
Article 11 adds a traceability requirement: on request from the market surveillance authority, economic operators shall identify, for a period of at least 10 years, any economic operator who has supplied them with transportable pressure equipment and any economic operator to whom they have supplied such equipment.
If the date has expired or is missing
The first rule is the same as for any goods-in non-conformity: do not improvise. The second is specific: the cylinder is still a pressure receptacle, with everything that implies.
Do not fill the cylinder and do not pass it on
Article 8(1) of Directive 2010/35/EU prohibits making available and using until conformity is restored, and Article 2, point (5), puts filling inside the notion of use.
Segregate the cylinder, valve closed and cap fitted
The precautions against unintentional release in Article 4(3) and (4) of Regulation (EU) 2024/573 stay with whoever is in possession of the container, including during storage.
Record the finding
The date read, the notified body number if there is one, the condition of the markings, photographs. Article 8(1) requires the owner to document instances of non-compliance and the corrective measures.
Contact the cylinder owner or the filler
Refrigerant cylinders normally move inside a return system. Article 11(4) of Regulation (EU) 2024/573 requires whoever places refillable containers on the market to have binding arrangements for their return for refilling. The owner decides on the periodic inspection.
Do not move a filled cylinder as if nothing had happened
Transport is governed separately, by Directive 2008/68/EC. Clarify the situation before moving it, using section 14 of the safety data sheet and the applicable official text.
If the cylinder holds gas, plan recovery, not venting
Article 4(1) of Regulation (EU) 2024/573 prohibits intentional release into the atmosphere where it is not technically necessary, and Article 8(7) requires recovery of residual gases immediately prior to the disposal of the container, for recycling, reclamation or destruction.
Close the case in writing
What was found, who was told, what was decided and on what date. The record under Article 11 of Directive 2010/35/EU, of who supplied the equipment and to whom it was supplied, runs for at least 10 years.
Where it meets the F-gas Regulation
The two regimes meet on the same cylinder but answer different questions. Directive 2010/35/EU is about the receptacle: is it fit to hold gas under pressure? Regulation (EU) 2024/573 is about the contents: which gas, how much, who may receive it, and what happens to it at the end.
- Non-refillable cylinders. Article 11(3) of Regulation (EU) 2024/573 prohibits the import, any subsequent supply or making available, use or export of non-refillable containers for Annex I and Section 1 Annex II gases, empty or fully or partially filled; such containers may only be stored or transported for subsequent disposal. The detail is in the guide on non-refillable cylinders banned.
- Refillable containers. Article 11(4) requires undertakings placing refillable containers on the market to produce a declaration of conformity with evidence of binding arrangements for their return for refilling, identifying the relevant actors, their commitments and the logistical arrangements; the declaration is kept for at least 5 years. See the guide on cylinder return and refilling.
- Residual gas. Article 8(7) requires recovery of residual gases immediately prior to the disposal of the container. A cylinder taken out of service because its inspection expired does not go to scrap with gas in it.
- The label. Article 12(4) requires a clearly legible and indelible label, and Article 14(5) of Directive 2010/35/EU requires that no other marking impairs the visibility and legibility of the Pi marking. In practice: the product label does not go over the stamps.
For the movement side, the guide on transporting cylinders covers the F-gas duties and points to where the dangerous goods regime sits.
Goods-in checklist for the cylinder
- The Pi marking is present and legibleArticle 15(4) of Directive 2010/35/EU: visibly, legibly and permanently.
- The Pi marking is followed by the notified body numberArticle 15(6).
- There is a periodic inspection dateArticle 2, point (18), and Article 12(1).
- The date is accompanied by the responsible notified body numberArticle 15(7). A date with no body number does not match the directive's wording.
- The applicable interval has been checked at the right sourceThe Annexes to Directive 2008/68/EC, by gas and by type of receptacle, or the cylinder owner.
- The markings are not covered by paint, rust or labelsArticle 14(5): no other marking impairs the visibility and legibility of the Pi marking.
- The product label is separate from the markings and is legibleArticle 12(4) of Regulation (EU) 2024/573 and Article 1(2) of Regulation (EU) 2024/2174.
- You know who owns the cylinderThe owner decides on the periodic inspection and takes the cylinder back; Article 8 of Directive 2010/35/EU.
- The record of suppliers and recipients is keptArticle 11 of Directive 2010/35/EU: at least 10 years, on request from the market surveillance authority.
Frequently asked questions
Does the F-gas Regulation say anything about the cylinder's periodic inspection?
No. Regulation (EU) 2024/573 governs the gas, not the receptacle as pressure equipment. Periodic inspection belongs to Directive 2010/35/EU on transportable pressure equipment, read together with Directive 2008/68/EC, whose annexes set the procedures and the intervals.
What is the interval between two inspections?
It is deliberately not written on this page. Article 2, point (18), of Directive 2010/35/EU refers, for periodic inspection and the procedures governing it, to the Annexes to Directive 2008/68/EC, and Annex I, Section I.1, of that directive makes Annexes A and B to ADR applicable. The interval depends on the gas and on the type of receptacle and is taken from the official text in force or from the cylinder owner.
Can I use the cylinder if the inspection expired but the gas is fine?
It is not a question of gas quality. Article 8(1) of Directive 2010/35/EU says the owner shall not make available or use equipment that is not in conformity, including with the requirements for periodic inspection, until it has been brought into conformity. And under Article 2, point (5), "use" covers filling, temporary storage linked to carriage, emptying and refilling.
What exactly is the Pi marking?
Under Article 2, point (16), it is the marking which indicates that the transportable pressure equipment is in conformity with the applicable conformity assessment requirements set out in the Annexes to Directive 2008/68/EC and in the directive itself. Article 14(4) states that it is the only marking attesting that conformity, and Article 15(2) sets its minimum height: 5 mm, or 2,5 mm for receptacles with a diameter of 140 mm or less.
Can I paint or label the cylinder over the markings?
No. Article 14(5) of Directive 2010/35/EU prohibits the affixing of markings, signs and inscriptions likely to mislead third parties as to the meaning or form of the Pi marking, and requires any other marking to be affixed so that the visibility, legibility and meaning of the Pi marking are not impaired. The product label has its own place, set by Article 12(4) of Regulation (EU) 2024/573.
Who pays for and arranges the periodic inspection?
The directive places the duty not to use non-conforming equipment on the owner, in Article 8(1), and the duty to use only conforming equipment on the operator, in Article 9(1). In practice, refrigerant cylinders move inside a return system and the inspection is arranged by the owner. The commercial side is settled in the contract, not in the directive.
Official sources
The articles cited from the directives were read directly in the official texts. The inspection intervals are not reproduced; the page names the act they come from.
Currency of this page and limits of responsibility
This page explains the marking and periodic inspection regime, but it does not contain the inspection intervals or the exact stamping layout. Those come from the applicable official text and from the cylinder owner. The page does not replace the assessment of a notified body.
General information prepared by EgoLog from Union directives and regulations. It is not legal advice.
A cylinder with an expired inspection is still a pressure receptacle. Do not fill it, do not modify it and do not vent it deliberately. Confirm the steps with the cylinder owner and your national competent authority.