- What is the difference between these two leading scaffold standards?
- How to choose scaffold standards for the scaffold material?
Differences Between BS1139 and EN 39 Standard
What is BS1139:1990 Standard?
The BS1139: 1990 includes a series specifying the requirements for the design, construction, and testing of equipment for use in scaffolding and other temporary structures. It specifies requirements for steel tubing of the type traditionally used in tubular scaffolding and false work. Recommendations for the design of tubular scaffolding structures are given in BS 5973 and BS 5974. This standard was previously published as Part 1 of BS 1139:1982 which also contained specifications for aluminium scaffold tubes. With the exception of specifying one wall thickness only (i.e. 4 mm), this standard technically aligns with European Harmonization Document HD 1039. Tubing complying with this British Standard also complies with the requirements for type 4 only of HD 1039 and therefore can be classified and marked “EN 39” (see clauses 8 and 9).
BS 1139 is now published in separate Parts and Sections as follows.
— Part 1: Tubes;
— Section 1.1: Specification for steel tube;
— Section 1.2: Specification for aluminium tube;
— Part 2: Couplers;
— Section 2.1: Specification for steel couplers, loose spigots and base plates
for use in working scaffolds and falsework made of steel tubes
(Identical with HD 74);
— Section 2.21): Specification for steel and aluminium couplers, fittings
and accessories for use in tubular scaffolding;
— Part 3: Specification for prefabricated access and working towers;
— Part 4: Specification for prefabricated steel splitheads and trestles;
— Part 52): Specification for materials, dimensions, design loads and safety
requirements for service and working scaffolds made of prefabricated
elements (Identical with HD 1000).
(From BS1139:1990).
What is EN 39 Standard?
This British Standard is the official English language version of EN 39:2001.
It supersedes BS 1139-1.1:1990 which is withdrawn. This standard includes a tube with a wall thickness of 3,2 mm as well as the previous 4,0 mm. The other principle changes are contained in the European foreword of this standard. The UK participation in its preparation was entrusted by Technical Committee B/514, Access and support equipment, and ISE/8, Steel pipes, to Subcommittee B/514/28, Props, tubes and couplers, which has the responsibility to:
— aid enquirers to understand the text;
— present to the responsible European committee any enquiries on the
interpretation, or proposals for change, and keep the UK interests informed;
— monitor related international and European developments and promulgate them in the UK.
A list of organizations represented on this subcommittee can be obtained on request to its secretary.
Cross-references
The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. (From EN 39)
BS1139 VS EN 39 Standard
1. In Chemical Components:
- BS1139 Chemical Components: Carbon(C), Silicon(Si), Phosphorus(P), Sulphur(S), and Nitrogen(N)
Table 2 – BS1139 Chemical Composition- EN39 Standard Chemical Components: Carbon(C), Silicon (Si), Manganum(Mn), Phosphorum(P), Sulfur(S), and Aluminum(Al)
Table 3 – EN 39 Chemical & Mechanical2. Mechanical Property:
- EN 39 Mechanical Property(See Above Table)
– Yield Strength: Min 235 MPa
– Tensile Strength: 340-520 MPa
– Elongation: Min 24%
- BS1139 Mechanical Property (See Table 4):
– Yield Strength: ≥ 235 MPa
– Tensile Strength: 340-480 MPa
– Elongation:≥ 24%
Table 4 – BS1139 Mechanical PropertyThus for mechanical properties, EN 39 scaffold standard requires 40 MPa higher than BS1139 on tensile strength property.
3 Tolerance Requirement Comparision :
| Items | EN39 | BS1139 |
| Outerside Diameter | ±0.5mm | |
| Inside Diameter | Allow Insert Guage 37.7mm diameter | 40.3mm -2.6mm |
| Wall Thickness | – 10% Seamless -15% | – 10% |
| Mass | -7.50% | 4.37KG/M +12% – 8% |
| Length(Exact) | 0/+10 (≤6m) |
4 EN 39 and BS1139 Standard Requirement On Marking
- EN 39 Marking Requirement:
1) the number of this European Standard (EN 39);
2) the name or trade mark of the manufacturer;
3) the thickness type, 3 or 4.
Example of die marking – EN 39 xxx 4.
xxx = name or trademark of manufacturer
- BS1139 Marking Requirement
Tubes shall be marked by impressing at intervals not exceeding 1,5 m. The height of the characters shall be at least 4 mm and the impression at least 0,2 mm deep.
The marking shall show
— the name or trade mark of the tube manufacturer;
— the EN number “39”,
— the letter “A” or “B” for silicon content as appropriate;
— the nominal wall thickness “4”, which shall not be positioned immediately adjacent to the number “39”.
After application of the protective coating an additional durable mark shall be applied to the tubes at intervals not exceeding 1,5 m showing the name or trade mark of the coating applier.
5 Cost Comparision
6. For Different Types of Scaffolding Pipes
BS1139:1990 standard is main for 4.0mm scaffold tubes.
EN39 standard is for both 4.0mm and 3.2mm scaffold tubes
How to Choose EN 39 or BS1139 Standards
En 39 standards have requirements for both 3.2mm and 4.0mm scaffold tubes. Thus you can choose the right standard for your scaffold tube specifications.
The aluminum chemical composition makes the scaffolding tubes more toughness. Thus EN39 scaffold tubes are suited for low-temperature countries. They need less hardness in cold weather.
BS1139 is cheaper in cost. Thus if you want to save cost, can choose the BS1139 standard.