PT Provider PTS Bulgaria invites you to take part in proficiency testing scheme No. PTS 26/06-T-1, conducted through an interlaboratory comparison.
The PT scheme is in accordance with ISO/IEC 17043:2023 and includes the laboratory activity “Testing” of aggregates using the standard methods and characteristics indicated in the table below.
The product and the characteristics are within the scope of accreditation of PT Provider PTS Bulgaria of “PTS Bulgaria” Ltd.
Scheme timeline
01 | Start of the scheme
01 June 2026
02 | Application for participation
until 30 November 2026
03 | Dispatch of the proficiency test items to participants
by 21 December 2026
04 | Performance of testing and reporting of results
by 19 February 2027
05 | Final report and certificate of participation
by 31 March 2027
Applications may be submitted until 30 November 2026.
⚠️ After completing and submitting the Application for Participation in PDF format, the application date shall be the date of receipt of the completed application at the e-mail address specified in it.
⚠️ When applying through the electronic form on the website, i.e. through the electronic application, the application date shall be the date of receipt of the automatic e-mail containing the data filled in by you in the application.
More details are available in the Detailed Proficiency Testing Plan and in the Invitation for Participation in section “Documents for Participation”.
Item of the proficiency testing
AGGREGATES
TESTING
| Code of the standаrd | Parameter | Number of participations |
|---|---|---|
*EN 933-1, including Clause 7.1 “Washing” |
Particle size distribution /cumulative percentages passing through sieves: 4 mm, 2 mm, 1 mm, 0.500 mm, 0.250 mm, 0.125 mm/ (mean value of three determinations for each sieve) |
|
*EN 933-1, including Clause 7.1 “Washing” |
Fines content /percentage of fines passing the 0.063 mm sieve/ (mean value of three determinations) |
|
*EN 933 8+A1 |
Sand equivalent, SE(10) (mean value of two or three individual determinations) |
|
*EN 1097 3 |
Loose bulk density, ρb (mean value of three individual determinations) |
|
*EN 1097 5 |
Water content, w (mean value of three individual determinations) |
|
*EN 1097 6, Clause 9 “Pyknometer method” |
Apparent particle density, ρa (mean value of three individual determinations) |
|
*EN 1097 6, Clause 9 “Pyknometer method” |
Oven-dried particle density, ρrd (mean value of three individual determinations) |
|
*EN 1097 6, Clause 9 “Pyknometer method” |
Saturated and surface-dried particle density, ρssd (mean value of three individual determinations) |
|
*EN 1097 6, Clause 9 “Pyknometer method” |
Water absorption, WA24 (mean value of three individual determinations) |
|
*EN 1097 6, Annex A, Clause A.4 “Pyknometer method for pre-dried particles” |
Pre-dried particle density, ρp (mean value of three individual determinations) |
* The tests are performed according to the latest valid version of the specified standard test method.