Radiation Therapy QA Tests & Tolerances

Photon output constancy daily tolerance

3%

Electron output constancy daily tolerance

3%

Localizing lasers should be tested ___ and within ___ of standard?

Daily, 2mm

Optical Distance Indicator (ODI) frequency & tolerance

Daily, 2mm

Jaw position indicators frequency & tolerance

Daily, 2mm

The door interlock should be checked:

Daily, functional

Audio/visual should be checked:

Daily, functional

Beam-on indicator should be checked:

Daily, functional

Electron output monthly tolerance:

2%

Photon output monthly tolerance:

2%

Light field/radiation (symmetric jaws) frequency & tolerance

monthly, 2 mm or 1% on a side

Light field/radiation (asymmetric jaws) frequency & tolerance

monthly, 1 mm or 1% on a side

Gantry/collimator angle indicators frequency & tolerance

monthly, 1 degree

Emergency off buttons should be checked:

monthly, functional

Table sag should be checked:

annually

Couch rotation to isocenter frequency & tolerance

annually, 2mm diameter

Gantry rotation to isocenter frequency & tolerance

annually, 2mm diameter

Photon/electron MU linearity is checked:

annually

CT number for water QA frequency & tolerance

daily; +/- 5 HU

MLC performance frequency & tolerance

weekly; OD<20%. Picket Fence Test

What is test used for MLC QA?

Picket Fence Test

Imaging QA frequency & tolerance

daily; 2mm for non SRS/SBRT; 1mm for SRS/SBRT

Laser guard lock should be checked:

monthly

Respiratory gating should be checked:

monthly

What is used to check light and radiation field agreement?

Ready pack film; done monthly

Mechanical isocenter (collimator) frequency & tolerance

annually, 2mm

Mechanical isocenter (Gantry) frequency & tolerance

annually; 1mm

Radiation isocenter frequency & tolerance

Star pattern test; checks gantry, collimator, and couch. annually, 2mm diameter