BS1139 EN74 Class A & Class B Scaffolding

What is the Differences of BS1139 EN74 Class A & B Scaffold

In Scaffolding Industrial, Scaffold Tube and Fitting System is still very Popular For Its Economy Cost Than System Scaffold, Flexible Shape Assembly and High Safety Load Capacity.
We have BS1139 Standard and EN 74 British Standard in Construction Scaffolding Pipe and Fitting System, Those Are The Most Using Scaffolding Standard Not Only For Traditional Civil.Residential and Building Construction, But Also Industrial Scaffolding, Commercial Scaffolding Globally and Internationally.
We can see BS1139 and EN74 standard Popularly Mentioned in Construction and Engineering.
BS 1139 is the standard that specifies the specifications for size, length, thickness, type of material, load capacity, etc. of scaffolding materials, including tubes tightly linked by a fitting system of clamps, couplers, putlog, boards, ladders, etc., forming a tube and fittings scaffolding system.

>> BS 1139 Standard For Scaffold Materials

En74 standard is a standard for scaffolding couplers only. It is used mostly for double and swivel coupler, sleeve coupler.
The requirement on scaffold couplers are same as BS1139. But there are EN74 Class A and Class B.
EN74 Class A is a initial standard requirement on Slip, Distortion and Other Characters to ensure safety construction.
While EN74 Class B is higher standard requirement, that distortion requirement is much higher than EN74 Class A and safer for heavy duty construction loading construction.

How to Choose Standard for Different Construction ?

For Drop Forged Double Coupler, EN74 Class B is always requirement by Oil Gas Companies. While Drop Forged Swivel Coupler, EN74 Class A is accepted by Oil Gas Companies.
Construction Projects Using OD48.3×4.0mm Scaffold Tube Class Material, better Choosing Drop Forged Scaffolding couplers. While OD48.3×3.2mm Scaffold Tube Material, Both Drop Forged or Pressed Steel Scaffolding Couplers are good choices.
On Water Project, should using hot dip galvanized drop forged couplers for durable reason. E-galvanized Scaffold Couplers are economy but easier rusty.