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(d) Minor Injuries

Persons cut by glassware, injured by hypodermic needles, etc., should wash the injured part under a strong stream of water immediately following the injury. A venous-return tourniquet may be applied if the material is unusually toxic. If it is ascertained that the injury was caused by an item bearing a hazardous amount of material, a biopsy section of the wound should be analyzed. Excision of the part to reduce further body absorption may be indicated in extreme cases.

(e) Inhalation

Persons inhaling radiotoxic fume, spray, or dust, should be treated to stimulate removal of the toxic material from the lung.

VI. Transportation

1. Shipment of Isotopes

The shipment of radioisotopes should be made in accordance with the regulations of the Interstate Commerce Commission, and with any further specific restrictions of authorized distributors of radioactive material (see appendix 3). The formal regulations cover interstate rail, truck, and water transportation. Transportation by air operates under an interim arrangement (see appendix 3).

2. Movements in the Laboratory

Each laboratory or institution should have a central controlled storage location for incoming isotope shipments. The minimum amounts of active material necessary for the intended processing should be withdrawn from this store, and any excess returned promptly after the operation. Movements of millicurie or greater amounts should be governed by written transfers. Each laboratory supervisor is then aware of the total activity problem in his group. Transfers from the central store to each laboratory should be made in properly shielded containers, and liquid shipments should be protected against spills. Within the laboratory, the active material shall be kept in a specified safe work place. Transfers from one place to another should be reduced to a minimum, and, when necessary, should be made with shielding adequate to protect all personnel in the laboratory. The general rules for such shielding may be deduced from the regulations prescribed for the shipment of isotopes outside the laboratory (see appendices 2 and 3).

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FIGURE 1.-Thickness, T mm, of typical materials required to stop completely beta-rays of maximum energy, E MEV.

Appendix 2. Gamma-Ray Shielding

1. Required Shield Thickness

The table given below may be used to determine the required thicknesses for shielding from gamma-ray sources in the laboratory.

Select column for energy required (use next higher if exact value is not given). Entry gives thickness in centimeters of lead for different source strengths at 1 m for 8 hr/day to give 50 mr. Add algebraically the correction terms for other

working ranges or times, and multiply by factor for shield material.

Example: An iron shield is required for the manipulation of 500 me of radioactive material emitting 1.8-Mev gamma rays at a minimum working distance of 50 cm, and for 4 hr/day.

Shield thickness=(8.60+2.77-1.39) X 1.43 14.3 cm of Fe, in which (a) (b) (c)

a=basic entry.

(d)

b=correction for danger range=50 cm.
c=correction for 4 hr/day.
d=conversion from Pb to Fe.

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+.56 +1.08

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-0.17-1.06 -2.04 -2.60 -3.59 -4.16 -4.42 -4.52 -4.52
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-.71 -1.36 -1.73 -2.39 -2.77 -2.95 -3.01 -3.01
-.35 -.68 -.87 -1.20 -1.39

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-1.51

+2. 34 +2.39

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NOTES

(1) Source activity is quoted in millicuries or curies, where 1 curie is that amount of radioactive material that disintegrates at the rate of 3.7 X 10 10 disintegrations/second. However, the table is computed on the further assumption that each disintegration yields one gamma photon of the selected energy. This will lead to inaccuracies whenever the disintegration is complex. accurate calculations can be made by obvious methods when the disintegration scheme is known.

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(2) The tabulation ignores the increased effective transmission of shields under wide beam irradiation.

(3) This form of shielding table (prepared by C. C. Gamertsfelder) is intended to form a guide to rapid erection of temporary shielding structures in the laboratory. Where permanent installations of maximum economy are planned, more detailed calculations by conventional methods are required.

Appendix 3. Shipping Rules

I. Interstate Commerce Commission Regulations The Interstate Commerce Commission requested the Bureau of Explosives, Association of American Railroads, to formulate regulations for adoption. The Bureau of Explosives was assisted by the Subcommittee on Shipment of Radioactive Substances of the Committee on Nuclear Sciences of the National Research Council. The regulations became effective January 25, 1948. The following is an excerpt of those rules that will apply to expected shipments of radioisotopes.

MAXIMUM LIMITS OF SHIPMENTS

Not more than 2 curies of radium, polonium, or other members of the radium family, and not more than 10" disintegrations per second of all other radioactive materials may be packaged in one outside container for shipment by rail express except by special arrangements and under conditions approved by the Bureau of Explosives.

EXEMPTIONS FROM PACKING, LABELING, AND MARKING REQUIREMENTS

Radioactive materials are exempted from prescribed packing requirements provided they fulfill all of the following conditions:

1. The package must be such that there can be no leakage of radioactive materials under conditions normally incident to transportation. 2. The package must not contain more than 0.1 millicurie of members of the radium family or the equivalent amount of plutonium, and not more than 5 × 106 disintegrations per second of strontium 89, strontium 90, or barium 140, or 50×10° disintegrations per second of any other substance.

3. The package must be such that no significant alpha or beta radiation is emitted from the exterior of the package, and the gamma radiation at any surface of the package must be less than the equivalent of 10 milliroentgens of radium gamma radiation filtered through one-half inch of lead for 24 hours.

PACKAGING AND SHIELDING

SPECIAL HAZARDS.-Radioactive materials which present special hazards due to their tendency to remain fixed in the human body for long periods of time (i. e., radium, plutonium, strontium) must, in addition to the packing described below, be packed in inside metal containers, specification 2R, or other containers approved by the Bureau of Explosives. Quantities and materials considered under this heading will be determined by the Bureau of Explosives.

PACKAGING AND SHIELDING.—(1) All radioactive materials must be so packed and shielded that the degree of fogging of undeveloped photographic film under conditions normally incident to transportation (24 hours at 15 feet from the package) will not exceed that produced by 11.5 milliroentgens of radium gamma rays filtered by one-half inch of lead,

(2) The design and preparation of the package must be such that there will be no significant radioactive surface contamination on any part of the container,

(3) The smallest dimension of any outside shipping container for radioactive materials must not be less than 4 inches,

(4) All outside shipping containers must be of such design that the gamma radiation will not exceed 200 mr/hr or equivalent at any point of readily accessible surface. Containers must be equipped with handles and protective devices when necessary in order to satisfy this requirement,

(5) The outside of the shipping container for any radioactive material, unless specifically exempt from packaging requirements, must be a wooden box, Specification 15A or 15B, or a fiberboard box, Specification 12B (Bureau of Explosives), except that equally efficient containers may be used when approved by the Bureau of Explosives,

(6) Radioactive materials which emit gamma rays must be packed in suitable inside containers completely surrounded by a shield of lead or other suitable material of such thickness that at any time during transportation the gamma radiation at one meter from any point on the radioactive source will not exceed 10 milliroentgens per hour for hard gamma rays, or that amount of radiation which will have the same effect on film as 10 mr/hr of radium gamma rays filtered through one-half inch of lead. The shield must be so designed that it will not open or break under conditions normally incident to transportation, and must be sufficient to prevent the escape to the exterior of the outside shipping container of any corpuscular electrically charged radiation,

(7) Radioactive materials which emit only corpuscular electrically charged particles must be packaged in suitable inside containers completely shielded so that at any time during transportation the radiation measured from any point on the shipping container will not exceed the following limits:

(a) Ten mr/hr for hard gamma rays, or that amount of radiation which will have the same effect on film as 10 mr/hr of radium gamma rays filtered through one-half inch of lead,

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