CSP-11 CSP-11 D6.01 · Domain 6 · Occupational Health and Applied Science · 10%
Radiation
An industrial radiography technician proposes finishing a weld exposure while standing 2 ft from a source position measured at 8 mR/h because the task will be brief and a disposable coverall is available. Your decision is to control access, use time-distance-shielding correctly, and distinguish exposure in mR from personal dose.
Updated . Independent CSP-11 practice. Not BCSP-endorsed. No pass guarantee.
Decision rule
Time, distance, shielding. Inverse-square only for a point source in the right geometry.
A badge is not shielding.
In 20 seconds
- Time, distance, shielding.
- Inverse-square only for a point source in the right geometry.
- Distinguish ionizing and non-ionizing radiation decisions.
- Calculate an illustrative dose rate change when distance doubles.
How to apply Radiation
THEORY: Dose ≈ rate x time when rate is steady. Double distance → about 1/4 intensity for a point source. CALC: If rate is 8 mrem/h for 2 h → 16 mrem. TI-30XS: 8x2=. Do not invent build-up factors. FIELD: Source stored next to a desk. Move it; add shield; limit time. ASSESS: Calling a 2-ft move ‘zero dose’ is the trap.
Worked case
Wrong first move: Longer briefing next to the source. Correct move: Move, shield, then time.
Why the rule holds
Related: 61, 68.
Same rule, different setting
A tech wants to “get it done” standing at 2 ft from a radiography camera on a pipeline weld because a paper gown is in the SDS. Distance can still change. You are the CSP. The question is time, distance, shielding — not a gown as a half-life.
A tech wants to “get it done” standing at 2 ft from a density gauge on a compaction lift because a paper gown is in the SDS. Distance can still change. You are the CSP. The question is time, distance, shielding — not a gown as a half-life.
Picture / model
Control ionizing-radiation work through authorization, access control, time, distance, shielding, surveys, and dosimetry; use inverse-square arithmetic only when source geometry and measurement conditions justify it.
Exam traps
Original SafePath contrasts for Radiation. These are study traps, not recalled BCSP items.
| Trap | Correct read |
|---|---|
| Time | Stay time = dose limit / dose rate — admin after geometry |
| Distance | Inverse square for a point source: 2× distance → ¼ intensity |
| Shielding | HVL / TVL of a specified material — not a paper gown |
| Half-life | Nuclide decay — not the worker’s stay time |
| Non-ionizing | Laser/RF/UV controls — different physics than I∝1/d² gamma |
Field move
Eight times (2/4) squared is 2, while the inverse-square approximation holds.
Scenarios
Scenario 1 · Fundamental · CSP-11 D6.01
A compact unshielded point source has a measured exposure rate of 8 mR/h at 2 ft. Assuming the inverse-square approximation remains valid, what rate is predicted at 4 ft?
Best action: 2 mR/h, because 8 × (2/4)² = 2.
Why: Evaluate the best response. The unshielded point source is 8 mR/h at 2 feet. At 4 feet the inverse-square estimate is 8 times (2/4) squared, which is 2 mR/h. A linear cut, an unchanged rate, and a reversed ratio are different arithmetic. 4 mR/h, reducing linearly with distance. — 4 mR/h reduces the…
Scenario 2 · Applied Scenario · CSP-11 D6.01
A survey reads an external dose-equivalent rate of 20 mrem/h in a controlled training scenario. A job-specific planning budget is 100 mrem. Ignoring other contributions, what exposure time reaches that budget?
Best action: 5 hours, from 100 mrem ÷ 20 mrem/h.
Why: Evaluate the best response. The survey reads 20 mrem/h and the planning budget is 100 mrem, ignoring other contributions. Time is 100 divided by 20, which is 5 hours. 2,000 hours, by multiplying dose and rate. — Multiplying dose and rate gives 2,000, which is not a time. 100 hours, treating the bud…
Scenario 3 · Applied Scenario · CSP-11 D6.01
A paper gown is offered as half-value shielding for an industrial gamma source. What should the radiation safety lead do?
Best action: Use characterized shielding or source shuttering, distance, and time controls appropriate to the radiation and verify the resulting field.
Why: Evaluate the best response. A paper gown is offered as half-value shielding for an industrial gamma source. Use characterized shielding or a shutter, plus distance and time, and verify the field. Gown color and a longer stay do not attenuate the gamma. Assume any paper gown halves penetrating gamma…
If the stem says this
| Stem signal | Best direction |
|---|---|
| secure source | Authorized source control, interlocks and access restrictions precede individual time calculation. |
| increase distance | Under point-source assumptions, rate at distance d₂ equals rate at d₁ times (d₁/d₂)². |
| minimize time | Estimate dose as rate times duration only while the rate is approximately constant and the route is controlled. |
| choose shielding and verify | Shield selection depends on radiation type and energy; survey actual locations and monitor occupational dose as required. |
Check before you leave
- ✓ Distinguish ionizing and non-ionizing radiation decisions.
- ✓ Calculate an illustrative dose rate change when distance doubles.
- ✓ Use time multiplied by dose rate with consistent units.
- ✓ Check source geometry, shielding and survey evidence before field authorization.
- ✓ Check geometry before using inverse square.
- ✓ Multiply time by rate only with compatible units.
Blueprint mapping
Radiation is the SafePath study class for CSP-11 D6.01 inside CSP-11 Domain 6, Occupational Health and Applied Science (10%). This domain combines occupational hygiene with applied science: exposure assessment, public health, toxicology, ergonomics, chemistry, and physics.
SafePath uses the publicly posted CSP-11 outline as a study map. It does not reproduce official exam content, and it is not affiliated with or endorsed by BCSP or Pearson VUE.
Practice / flashcards / formulas
More classes in Occupational Health and Applied Science
Nearby lessons mapped to the same CSP-11 domain.
CSP-11 D6.01
Other classes on this task
Guides that use Radiation
- CSP calculationsIncident rates, noise, ventilation, and unit checks
- Formula deskNamed expressions used in occupational-health items
- Manufacturing safety study guideExposure, noise, and process controls
- CSP-11 exam prep guideDomain weights, sample items, and a study sequence
- CSP-11 blueprint and weightsSeven published domains and the class map
Radiation study questions
- What decision does the Radiation class train?
- Time, distance, shielding. Inverse-square only for a point source in the right geometry. This is independent SafePath CSP practice for CSP-11 D6.01. It is not an official BCSP item and it is not a pass guarantee.
- What exam trap shows up in Radiation?
- A common miss treats this as sufficient: Time The stronger read is: Stay time = dose limit / dose rate — admin after geometry
- How does Radiation map to the CSP-11 blueprint?
- SafePath maps this class to CSP-11 D6.01 in Domain 6, Occupational Health and Applied Science (10% of the published blueprint). Use the public outline for study planning. SafePath is not affiliated with or endorsed by BCSP.
Verify
Verify: Confirm current certification requirements with BCSP and technical requirements with the cited authoritative standard.