The European design code for temporary work equipment and especially for scaffolding, NF EN 12811-1, defines the cross-section non-linear plastic resistance criterion, which requires includ-ing initial imperfections in the global analysis of the structure. At the same time, the European de-sign code for steel structures, Eurocode 3 Part 1-1, establishes the buckling resistance criteria en-abling to free ourselves from the modeling of initial imperfections. However, they do not offer the opportunity to exploit the non-linear plastic resistance capacities of the cross-section. Moreover, these buckling resistance criteria are often based on hypotheses and lead to inconsistencies be-tween the verification with cross-section criteria or with buckling criteria. The objective is to de-velop a procedure for analysis and design of access scaffold. The developed approach takes into account the interaction between section resistance and instability phenomena, and includes the influence of initial imperfections, such as initial defect of aplomb, lack of straightness and residual stresses. As far as possible, these effects will be decoupled. In order to verify the efficiency of the proposed procedure, several examples of typical scaffolding structures have been studied and the results prove the performance of proposed formulations.