The angle errors of a rotary table can be accurately measured by stepping off the angles with an optical caliper and computing table error from (1) the error readings at each angle measured and (2) the cumulative caliper error that will be evident when the circle is closed at 360', eliminating the necessity of adjusting the caliper to the exact setting.

Surface contamination with beryllium becomes a hazard to health only when the potential exists for resuspension in air in enough quantity and for enough time to exceed the prescribed standards for airborne exposures. There are several factors governing the rate and nature of resuspension phenomena. These factors include: the quantity and properties of the particular beryllium compound causing the contamination, the nature of the surface, activities in the vicinity, ventilation in the area which might affect the dilution of resuspended particles, and the presence of other control measures such as respiratory protection and use of wet methods. Generally, it has been found that the problem is minimal and can be easily controlled by exercising good judgement based upon consideration of pertinent factors governing resuspension, and a knowledge of the nature of beryllium toxicity.

The Chapman-Jouguet pressure and equation of state of the high explosives PBX 9404 and LX04-01 have been experimentally derived. To assure a strictly one-dimensional geometry, spheres of high explosives were used. Experimental measurements of the radius-time history of material accelerated by the explosive gases were used in conjunction with finite difference calculations of the hydrodynamic equations to obtain some previous inaccessible data on high explosives.