Target irradiation capsules of each type must be designed such that they can be adequately cooled by the coolant flow available outside the target-rod shrouds. Excessive neutron poison loads in experiments in target positions are discouraged because of their adverse effects on both transplutonium isotope production rates and fuel cycle length. Such experiments require careful coordination to ensure minimal effects on adjacent experiments, fuel cycle length, and neutron scattering beam brightness. Two positions are now available for instrumented target experiments: positions E3 and E6.