OBT Safety Protocols & Quality Assurance 2

Question 1

Which laser classification requires engineering controls and administrative controls but does NOT require protective eyewear for casual viewing of the beam?

Accepted Answer

Class 2

Answer

Class 2 lasers emit visible light at ≤1 mW and rely on the natural aversion response (blink reflex) to protect eyes, so casual viewing does not require eyewear.

Question 2

What does the term 'nominal hazard zone' (NHZ) define in optical beam therapy safety planning?

Accepted Answer

The area within which the beam irradiance exceeds the maximum permissible exposure

Answer

The NHZ is the spatial region in which the level of direct, reflected, or scattered laser radiation exceeds the applicable maximum permissible exposure (MPE).

Question 3

During a quality assurance check, a practitioner measures the output power of a therapeutic laser and finds it is 15% below the manufacturer's specified value. What is the most appropriate next step?

Accepted Answer

Document the variance and take the device out of service for calibration

Answer

A >10% output deviation typically exceeds acceptable tolerance; the device should be removed from service and sent for professional calibration before further patient use.

Question 4

Optical density (OD) of laser protective eyewear is defined as:

Accepted Answer

The logarithm (base 10) of the attenuation factor at a given wavelength

Answer

OD = log₁₀(H₀/H), where H₀ is the incident exposure and H is the transmitted exposure, so OD 4 means 10⁴ attenuation.

Question 5

Which standard is most commonly referenced in the US for safe use of lasers in health care facilities?

Accepted Answer

ANSI Z136.3

Answer

ANSI Z136.3 is the American National Standard specifically addressing safe use of lasers in health care environments.

(OBT) Optical Beam Therapy Certification Practice Test

(OBT) Optical Beam Therapy Certification Practice Test

OBT Safety Protocols & Quality Assurance 2