Center for Built Environment Research
School of Planning, Architecture and Civil Engineering

Amphora NDT

Amphora NDT Ltd was formed on the basis of the research and development work carried out by the School of Civil Engineering at Queen’s University Belfast, Northern Ireland, UK. We manufacture testing instruments which can be used to assess the strength and durability of both structures and materials and provide a range of testing services to characterise construction materials. The range of instruments manufactured by us includes Autoclam Permeability System (for testing different materials), Permit Ionic Penetration Test and Limpet Pull-off Test. By browsing through the pages of our site, we expect that you will be able to match most of your testing needs with what we can offer in terms of both instruments and services. It must be emphasised that the company is led by highly qualified academicians, with many years of research experience in the area of Non-Destructive Testing of construction materials. We are just a few 'bytes' away for you to discuss your testing and analytical needs with us.

Autoclam Permeability System


The Autoclam Permeability System measures the air permeability, unsaturated water permeability and water absorption (sorptivity) of concrete, brick masonry and stone masonry, both in the laboratory and on site. It can assess the quality of building materials in terms of these properties, both soon after the construction and at any time during the service life of structures. Any defects of the building materials due to interactions with the exposure environment can be detected at any time and appropriate remedial measures taken before the structure starts deteriorating.

The instrument, which is currently available in four different versions, is totally portable and easy to use on site. Non-skilled personnel can carry out the tests. The tests can be carried out without leaving any mark on the test surface, a unique feature that would be required, for example, while testing façades of structures. The total duration of each test is less than 30 minutes, which includes instrument setting up time. Up to 12 tests can be carried out using the battery pack available within the instrument or run continually during the day if an external power supply is available. The data from each test is stored in the controller of the instrument and can either be recorded manually or transferred to a PC for further analysis.

The Autoclam is a well-established instrument, with more than 30 countries using it for a range of applications. Its widespread acceptance will be enhanced when the Round Robin Test (RRT) programme planned by a RILEM Technical Committee is carried out in September 2003.

There is potential for it to be used for testing soil, slates, floor finishes, timber, asphalt concrete, etc. Therefore, four different types of Autoclam are available, for further details contact Amphora NDT Limited. Contact information and a downloadable pdf brochure for all instruments are available towards the end of this page.

Permit Ion Migration Test


PERMIT can be used to assess the resistance of building materials to the transport of ionic species, such as chlorides, sulphates, etc., which are considered detrimental to the long-term performance of construction materials. The current procedure to determine this property of a building material is to test, in the laboratory, cores removed from structures. The test itself may last for three to seven days, depending on the quality of the material. The PERMIT requires only a test duration of less than 8 hours and is the only instrument available at present to measure on site the resistance of building materials to ionic transport.

In this test the test surface is saturated prior to fixing the instrument, to ensure that the flow of ions due to the applied field is through saturated capillaries. Steady state conditions are achieved within 6 hours, depending on the type and quality of material tested, and the rate of steady outflow of ions through the near-surface zone of the material is used to calculate the coefficient of ionic migration (diffusion), as defined in Nerst-Planck relationship.

For further information contact Amphora NDT Ltd. Contact information and a downloadable pdf brochure for all instruments are available towards the end of this page.



The LIMPET was originally developed to assess the strength of concrete on site. However, it now a standardised test to determine the bond strength of patch repairs and this has now become its principal application. However, the instrument can also be used to assess the progressive deterioration of concrete and other building materials due to their interactions with the exposure environment. Research carried out by the Structural Materials Research Team at Queen's has found good correlations between salt weathering of normal concrete and pull-off tensile strength.

The test is considered to be partially destructive as it leaves a small mark on the test surface due to the removal of a small piece (50mm diameter) of the material being tested. However, this level of damage is considered to be acceptable given that the alternative is to remove cores from the structure and test them in a laboratory.

The advantages of Limpet are many, which include the fact that no preplanning is requires, as illustrated in the figure above. It compliments the Autoclam Permeability tests because both the Limpet disc and Autoclam ring can be fixed to the test surface at close proximity to each other. This is a unique advantage when repair materials are assessed on site.

For further information contact Amphora NDT Ltd. Contact information and a downloadable pdf brochure for all instruments are available towards the end of this page.

Resistivity Sensor Array

Other Concrete Testing and Monitoring Equipments

Other instruments, such as Teredo for determining the in-situ abrasion resistance of floors, and embedded sensors for monitoring chloride, water and temperature fronts in concrete are available on request.

Contact Information

Amphora NDT Limited

1 Chlorine Gardens,



N. Ireland

Ph: +44 (0)28 9066 4964

Mob: +44 7900 316 996


Instrument brochures pdf document

Autoclam brochure
Permit brochure
Limpet brochure