4.2 Written Directives and DOT Shipping

Two high-yield streams often appear together on CNMT items: written directives (WD) for medical use under 10 CFR Part 35, and DOT rules for shipping and receiving packages. One protects the patient from wrong therapy; the other protects workers, carriers, and the public in transit.

Written Directives: When Required

A written directive is an authorized user’s written order for a specific patient before certain administrations. You must have a WD before:

Exam trap: I-131 sodium iodide above 30 µCi always pulls WD rules. Therapy nuclides (Lu-177, Y-90, high-activity I-131) are classic WD scenarios.

Required Elements

For unsealed byproduct material, the WD must include at least:

1. Patient’s name (clear identity)
2. Radioactive drug
3. Dosage (activity)
4. Route of administration
5. Authorized user signature and date — before administration

For I-131 NaI > 30 µCi, rules emphasize patient name, dosage, and AU signature/date; still verify identity and order in practice.

Before you dose

• Verify two patient identifiers against the WD and order.
• Confirm radiopharmaceutical, activity, and route match the WD.
• Assay in the dose calibrator; document measured activity and time.
• If activity is outside the prescribed range or WD, stop and contact the AU.
• After administration, record what was given. Technologists do not freestyle therapy activities.

Written directives sit inside quality management: policies to catch wrong patient, wrong drug, wrong route, and dosage errors before they become medical events (Section 4.1).

DOT Packaging Basics

Radiopharmaceuticals move under DOT Hazardous Materials rules. Most unit doses and many generator-related shipments arrive in Type A packages—tested for normal transport conditions within Type A_1/A_2 activity limits.

Outer packaging preserves containment and shielding. Inner pigs (lead/tungsten) cut external dose; the outer container provides impact protection and a labeling surface.

Labels and Transportation Index

The Transportation Index (TI) equals the maximum dose rate at 1 meter in mrem/h, rounded up to the nearest tenth (0.13 mrem/h → TI 0.2). TI drives segregation and storage distance. Labels also show radionuclide and activity. Do not cover required labels in transit; empty returns must have radiation labels removed or obliterated when no longer applicable.

Package Monitoring on Receipt

Under 10 CFR 20.1906 and license procedures, for White-I / Yellow-II / Yellow-III packages (and certain other cases):

1. Visually inspect for damage or wetness.
2. Within 3 hours of receipt during working hours (or within 3 hours of the next working day’s start if after hours), measure external radiation (surface and, as required, 1 m) and removable contamination with wipe tests.
3. Compare with regulatory/package limits and internal triggers.
4. If limits are exceeded or damage is suspected, notify the RSO, and when required the carrier and NRC, and isolate the package.

Do not open a crushed, leaking, or unexpectedly “hot” package at the front desk. Use PPE, shield as needed, and follow RSO direction.

Returns and product labels

Empty pigs returned to a pharmacy must not display active radiation labels if empty (or must be labeled correctly if residual activity remains). Survey/wipe returnables so you do not ship contamination to the vendor.

Unit-dose / shipping label content typically includes radiopharmaceutical name, activity, assay date/time, concentration and/or volume when relevant, expiration / beyond-use time, patient or unit-dose identifiers, and lot/batch data as required. Reconcile label, assay, order/WD, and patient—decay may make a delayed labeled activity wrong for administration time.

Exam Hooks

• Therapy Lu-177 or I-131 without AU-signed WD → stop.
• I-131 NaI > 30 µCi → WD required.
• Surface 0.4 mrem/h, negligible at 1 m → White-I.
• Surface 20 mrem/h, 0.7 mrem/h at 1 m → Yellow-II, TI 0.7.
• Yellow-II arrives 10:00 on a workday → survey/wipe by 13:00.
• Crushed package, high wipes → RSO + isolate + notifications.