The “Raccomandazioni” are real modifications of the original text of the Raccolta VSG, therefore the allowable stresses are similar to those in EN 13445 part 3. The program VSG contains different moduli for the calculation of cylindrical shells, cylindrical tube headersof watertube boilers, domend ends, opening reinforcements, flanges, flat covers, stiffened and unstiffened tubesheets of firetube boilers, etc., together with an extensive material database containing the most important UNI, DIN, EN and ASME materials listed in the Raccolta “M”. As in all the other Sant’Ambrogio packages, the user may purchase a licence only for the moduli that he will actually use. The calculation of stresses due to nozzle loads according to WRC 107/297/537 is also an option that can be added to the software. The calculation of the test pressure required by the Raccomandazioni and by the PED is also possible.