sorry it took me so long to get back. i think it could be easy if explained. what it says is,maximum area. the total area of porosity permitted,as determined from the radiographic film, is based on one percent of desighn material thickness "T" per each inch of weld being inspected.for calculation, the following formula applies: total area of pores permitted in 1inch length of weld = 0.01T inch x 1 inch. hence, for any 6 inch length, the total area of pores permitted will be 0.06T square inch.
the other says, randomly dispersed porosity. randomly dispersed porosity shall not exceed the limits of figures 6 through 15 for weld thicknesses 1/8 to 4 inches. i am using figure 10 has some drawings of differant porosity and at the bottem it says, radiographic porosity class 1 and class 2 (1 percent T/inch per 6 inches), T equals 1/2 inch(0.030in2 total porosity area). the 2 behind the 0.030in is smaller meaning squared i guess. i just can't figure from all this how much porosity is allowed per inch or even 6 inches. totally confused.