DSL Derrick Inspectors are qualified to the API Approved Training for API 4G Drilling Structure Inspections. DSL is also API 4F licenced for the design & manufacture of Drilling Structures & 8C for Crown Blocks and Hoisting System. Therefore, both Inspector and Company are the qualified solution for the inspection of your drilling structure, whether it is a Derrick, Mast and Substructure, Trailer Rig, Carrier Rig, Derrick Equipment Set or any other Drilling Structure.

DSL are an API Certified Training Provider for

A quick search of the internet will present you with a whole variety of different companies offering to undertake these inspections for you. You don’t have to look too deeply to realise that most of these are either unqualified, lacking the relevant product knowledge or experience therefore hiding these facts with words and reference to specifications to distract you from the fact that they are simply not qualified.

The facts remain that unqualified companies and/or personnel increase the risk to your operations where as DSL represents both a reduction in risk and a positive move toward a safer working environment.

(Click on specification to view our current certificate)
Derrick/mast related incidents on land rigs and offshore derricks still represents an unacceptable amount of oil rig accidents, which is not helped by untrained or inexperienced personnel and companies inspecting drilling derricks.
The API approved course that DSL has developed and successfully implemented now provides the industry with the standard with which to move forward and further improve the safety statistics of derrick related incidents.

DSL carries out API 4G Cat III & IV Inspections all over the World on a day to day basis from our operations in Singapore, Dubai, India, UK, Brasil with operations in Houston opening in the near future.

As an API 4F & 8C licence holder you have the assurance that in the event that an issue of significant concern is found within your drilling structure, that our field staff have the benefit of calling on our internal Engineering Department to review and make qualified recommendations.

The Competency of our personnel is further enhanced by our OPITO Accredited Competency Management System and our Derrick Technicians are also trained and qualified to the API Approved Training for Derrick Technicians.

If you would like a quote for an Inspection click here or contact us at

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If there is any particular concern regarding your Derrick/Mast or its accessories please feel free to contact us for technical advice from our Engineering Department at

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