Ionizing Radiation CONSTRUCTION SPECIFICATIONS FOR INDUSTRIAL X-RAY OR GAMMA ENCLOSURES 1 All X-ray or gamma enclosures to be provided with protective barriers of sheet lead or equivalent protective materials of assured quality, uni formity and permanency 2 Sheet lead to be mounted so as to avoid cold-flow and to be protected from mechanical damage Sheet lead less than 1/16 in thick to be bonded to rigid supporting materials 3 Sheet lead joints to be overlapped with a lap at least 1/2 m , or twice the thickness of the sheet, which ever is greater Joined sheets to be m direct contact Butt joints may be used provided the welded or burned seams are not less than the minimum lead equivalent required 4 Joints between different kinds of protective materials to be designed to avoid leakage through the lighter material Where floor (or ceiling) is not lead-lined, lead sheet on wall to extend into floor (or ceiling) Joints may be flanged to provide, at the joint, protection equivalent to lead-lined walls 5 Comer construction to provide same protection as that required for body of enclosure 6 Lead sheets not to be perforated by nails, bolts or other fasteners unless they are adquately covered to give protection equivalent to unperforated lead sheet 7 Openings in barrier for pipes, conduits, air ducts, louvers, etc , to be pro vided with baffles so that transmitted radiation does not exceed that trans mitted by the barrier itself 8 Observation windows and doors to have the same lead equivalent as that required of surrounding wall 9 Where floor is not lead lined, door sill to be provided with lead baffle, lead covenng of door to overlap door jamb Radiation scattered under door or passing through door clearance spaces, not to exceed that trans mitted by door Fig 44-10 lfications are enumerated in Fig 44-10 Special attention must be given to the de sign of the joints between different protective materials, such as lead and concrete, in order to avoid leakage due to scattering through the lighter matenal This is illustrated in Fig 44-11 Where the control room, office space or film processing room is located adjacent to the shielded enclosure and ready access from 1464

The uses are the same as for Euston Superior Grade White Lead, however, Euston Standard Grade White Lead is more especially adapted for dry color manufacturing.

For detailed information on the most effective use of "lead" in your paints . .. write to Lead Industries Asso ciation, 420 Lexington Avenue.

For detailed information on the most effective use of "lead" in your paints . .. write to Lead Industries Asso ciation, 420 Lexington Avenue.

Lead pigments naturally are and two coats of pure white lead paint.

Reductions of from 20 to 33S in the lead thickness have been tried, the reduced lead sheath being jacketed with neoprene.

Lead Industries As** utn*n.

February 24 -- "Spokesman for Lead Industry Questions Whether 'Getting Lead Out' is Answer to Auto Pollution."

Lead Industries Association, Inc., Facts about lead and Industrial Hygiene, p. 5.

Lead - Kehoe The Plasma-cell Partition of Blood Lead - Eambach, Kehoe and Logan P.S.

Requirementa for the Hygienic Control of the Manufacture, Distribution and Use of Lead Tetraethyl for the Preparation of Motor Fuel* Foreword The hygienic control of operations involving the production or use of lead tetraethyl differs from that required in the more common lead trades, in that there is serious danger of exposure to a liquid organic lead compound, as well as to inorganic lead compounds* Exposure to lead tetraethyl arises from the volatility of this compound and also from its absorbability through the healthy unbroken skin* Its vapor pressure la such that under the conditions of equilibrium at 25C, a concentration of approximately 5 mgm* of load per liter of air will exist.

LEAD DISEASES.

National Lead Co.

Reductions of from 20 to 33S in the lead thickness have been tried, the reduced lead sheath being jacketed with neoprene.

They buy principally from the National Lead Company.