The management of trestles

Trestles are often mistaken for lifting machines instead of a supportive platform on which goods or plants are normally placed or stored.

It is therefore clear that trestles do not have to be load tested by registered ECSA LMIs at specific intervals as required in OHSA DMR 18.

The relevant SANS for Trestles is: SANS 1854:2005 The design and manufacturing of trestles.

Most of the time trestles are used as a supportive stand to stack either a load or equipment such as plant, pipes or machinery or as a working platform for welding, assembly of parts or components.

Definition of trestles in SANS 1854: A trestle is a self-supporting metal stand for supporting scaffolding boards to provide a working platform.

The Standard requirements for trestles are: 1. Basic material to be used for fabrication, normally steel or wood. 2. Design and construction. 3. Type, either adjustable or fixed height. 4. Finishing: Paint with a protective coating to protect the trestle against surface corrosion. 5. Stability: The trestle must have a low centre of gravity (not higher than 30% of total height). 6. Load carrying capacity: The trestle must be designed to support a specific load and this load must be stated on the trestle as stated below. 7. Marking: Each trestle must be legibly, indelibly and permanently marked with a unique number and load carrying capacity (SWL). Where available, the manufacturer’s name should be marked as well. Suggested marking letter size at least 10 mm in height.

The method of measurement of vertical load-carrying capacity and test for stability and the test report requirements are described in the SANS 1854:2005.

Other design and construction requirements can be required, such as:

1. The trestle must be designed and signed off by an Engineer. 2. A drawing and a load test certificate must be included when delivered. 3. Three monthly inspections can be specified, according to a checklist. 4. Yearly non-destructive testing (NDT) can be done. Trestles requirements can be included in a User’s Fatality Prevention Standard or specified in a Company Operating Procedure. However, trestles need to be manufactured and managed onsite according to the South African National Standard, which is:

SANS 1854:2005 – The design and manufacturing of trestles.

The above information is given as a guide only and based on the writer’s personal opinion.

Phakamisa Safety Consultants,

+27 (0) 82 372 4595, potto@icon.co.za, www.phakamisasafety.co.za