The Commission internationale permanente pour l'épreuve des armes à feu portatives (English: Permanent International Commission for the Proof of Small Arms), abbreviated C.I.P., is an international organisation which sets safety standards for firearms. As of 2025 its members are 16 national governments, of which 11 are European Union states. The C.I.P. safeguards all firearms and ammunition sold to civilian purchasers in member states.
To achieve this, the firearms are proof tested at C.I.P. accredited Proof Houses. The same applies for cartridges. At regular intervals, cartridges are tested against the C.I.P. pressure specifications at the ammunition manufacturing plants and at C.I.P. accredited Proof Houses.
Quality control and proof process
Prior to firing cartridges in the firearm to be proofed, it is checked for its essential mechanical dimensions such all measures and tolerances in the chamber are verified. A visual inspection of the barrel is also performed. If the firearm passes these first steps, the standard proof takes place. The proof consist of firing two overloaded cartridges producing 25% more chamber pressure than the C.I.P maximum pressure limit for the same cartridge in its commercial version. For pistol, revolver, and rimfire cartridges the standard proof is performed with overloaded cartridges that produce 30% more chamber pressure than the C.I.P maximum pressure limit for the same cartridge in its commercial version. Voluntarily testing beyond the C.I.P. maximum pressure limit is also possible for consumers who intend to use their firearms under extreme conditions (hot climates, long series of shots, etc.). A proof mark is stamped in every successfully tested firearm. The C.I.P. does not test any further aspects regarding the correct functioning of the tested firearm. For example, aspects like projectile velocity, accuracy or the correct cycling of cartridges etc. are not part of the proofing process.
Primarily oriented towards the proof houses and manufacturers, the C.I.P. independently assesses, approves and publicizes manufacturer's data such as ammunition and chamber dimension specifications, maximum allowed chamber pressures, caliber nomenclature, etc. All this C.I.P. established data can be accessed by everyone.
Technical procedures describing how to perform proofing are also established by the C.I.P. and updates to the various test methods are issued in the form of "decisions". These decisions can also easily be obtained by everyone involved.
The C.I.P. formally distributes established data and decisions to the member states through diplomatic channels for ratification in each member state and publishing in their official journals. After official publication C.I.P. established data and decisions obtain(s) indisputable legal status in all C.I.P. member states.
Governmental organizations, like military and police forces and other firearms bearing public power agencies, from the C.I.P. member states are legally exempted from having to comply with C.I.P. rulings. This does not automatically imply that all firearms and ammunitions used by governmental organizations in C.I.P. member states are not C.I.P. compliant, since those organizations often choose to self-impose the relevant C.I.P. standards for their service firearms and ammunition.
History
Firearm safety tests were made compulsory at the beginning of the 16th century, for instance in Styria (Austria) by decree of Maximilian I of Habsburg on 12 September 1501, 1589 in London (England), and in the 17th century in Liège (Belgium). At that time, proofing was executed by "proofers" at public places. All firearms of reputable brands were proofed this way. Proof testing is compulsory in Belgium since the decree of Maximilian Henry of Bavaria dated 10 May 1672. The Liège Proof House was created at this occasion. Progressively, national proof houses were set up in other countries and proof marks were introduced.
In 1914, the director of the Liège Proof House in Liège, Joseph Fraikin (director from 1908 to 1946), was the originator of the creation of the Permanent International Commission for Firearms Testing.
The C.I.P. has progressively established a set of uniform rules for the proofing of firearms and ammunition to ensure the reciprocal recognition of the proof marks of each member states.
A conventionC.I.P Convention (French) between 8 member states was signed in 1969, ratified and converted into law in each signing state, so that the rules can be enforced to assure that every firearm and cartridge on the market has successfully passed the compulsory proofing and approval.
In 2014, The C.I.P. celebrated the centenary of its foundation 15 July 1914. It was created just 13 days before the beginning of World War I on 28 July 1914.
Member states
The current (2025) C.I.P. member states are:
Most recent member States: The United Arab Emirates became a member state on 9 April 2008. Local companies like Caracal International L.L.C. and ADCOM Manufacturing will benefit from a local proof house.
Portugal and Serbia became member States in 2025.
Former C.I.P. member state: (formally dissolved in 1992) The Permanent International Commission, confirming that the Socialist Federal Republic of Yugoslavia is no longer in existence, declared during the XXII Plenary Session that the proof marks of the Proof House at Kragujevac, Serbia, would no longer be recognised by the C.I.P. Member States with effect from 30 September 1992.
Precepts and aims The C.I.P. Convention has the following major precepts:aims of the CIP There is reciprocal acceptance of each country's proof marks, certifying the identity of the firearms and the satisfactory performance of the tests performed in accordance with the pre-set regulations; Tests are standardised to guarantee safety and their application methods; At least one state-controlled national Proof House exists in each country; Every member country enacts a law which makes it compulsory to perform the tests according to the methods, limits and procedures established by the convention.
The main aims of the C.I.P. are as follows: To select test pressure barrels to measure firing pressure and define the measurement procedures for use by official Proof Houses to determine pressure generated by test cartridges and the commercial cartridges fired by hunting, sport and defensive firearms and in machine tools; To establish the kinds of procedures to be followed in the official tests used for firearms and machine tools to guarantee every degree of safety; To adopt the most modern measuring techniques for the arms and ammunition testing procedures; To encourage standardisation of chamber and cartridge dimensions, testing methods and ammunition testing procedures; To examine laws and regulations issued by member states regarding official tests for firearms and ammunition; To declare which countries act in accordance with standard tests and publish a schedule of the proof marks applied by the official testing centres of these countries; In accordance with the above, to retract declarations when necessary, and modify the schedule when conditions are no longer valid.
Relations with manufacturers and internal functioning The C.I.P. is an organisation whose members are state authorities but the operations of C.I.P. and its decisions are fully delegated to professional people active in the firearms industry. This includes all the proof house directors and their collaborators, ammunition manufacturers, machine manufacturers, gunsmiths, ballistic specialists and so on. Two sub-commissions exist within the commission itself. The first technical sub-commission deals with the definition of measuring methods and determine the acceptable values while the second regulatory sub-commission defines and express the conditions for new uniform rules. Working parties within these sub-commissions are also created each time a subject needs to be discussed and experts on the subject are invited to participate in relevant meetings. They meet as often as considered necessary at various places to work on the subject they have been assigned to and report to their sub-commissions. After that, the C.I.P. votes in Plenary Sessions on submitted sub-commission proposals, resulting in decisions and the publishing of them. This implies that all decisions made by C.I.P., although enforced by law after publication, are the result of a cautious consensus between sensible and knowledgeable people in this field.
Firearms proofing
Small arms manufacturers and importers within C.I.P. member countries are obliged to request one of the accredited Proof Houses to perform proofing of all arms they manufacture or import. No small arm can be marketed in any C.I.P. member state without successful proofing in an accredited proof house, as regulated by the C.I.P.
After the successful proof test, two or three proof marks are applied to the main (highly stressed) parts of the arm: the barrel, the chamber (when not part of the barrel) and the locking mechanism.
These three essential parts are then weighed and their weight is recorded in a database together with the serial number.
Then a serial number indicating the year of proofing is marked on these parts. In case a firearm was voluntarily tested at a higher than required proof-test pressure superior proof marks are applied on the relevant parts.
Only after that is the arm released to the manufacturer or importer to sell or to deliver, if already sold.
Ammunition approval
The C.I.P. also enforces the approval of all ammunition a manufacturer or importer intends to sell in any of the C.I.P. member states. The ammunition manufacturing plants are obliged to test their products during production against the C.I.P. pressure specifications. A compliance report must be issued for each production lot and archived for later verification if needed. The cartridge boxes must also be stamped with a C.I.P. approved number to allow quality/safety traceability according to ISO 9000 principles in case of quality problem though C.I.P. predates the creation of ISO 9000.
Since the very beginning, the C.I.P.’s concern has only been related to arms/ammunition safety from the user's point of view. Thus the C.I.P. is only interested in chamber pressures and not interested in the velocity achieved by the projectiles. As a result, the compulsory ammunition safety control tests by the manufacturers themselves and their approval by the proof houses are only pressure related. The dimensional checking of the ammunition, as described in the C.I.P. Decisions, Texts and Tables, is left to the manufacturers themselves. Headspace is not checked, even on rimless cartridges with taper. The view is that in the very unlikely case (according to the current quality standards) the cartridge is too long, once pressed by the bolt, the pressure will rise too high causing rejection. If it is too short, firing will fail also causing rejection.
The manufacturers do make velocity measurements, however. These measurements are made during production for quality control with respect to the user's performance expectations of the product for its purpose.