DAILY QUALITY ASSURANCE PROCEDURE

LINEAR ACCELERATOR

MUHAMMAD SOHAIL PREPARED BY :

Quality Assurance of LINAC Machines : • To ensure the consistency of quality

of machine.

• Patient safety important.

• To ensure that it deliver right dose to the patients.

• To check if there is any mechanical or software errors.

CONTENTS

TURN ON PROCEDURE

MACHANICAL CHECKS WARMUP PROCEDURE

DOSIMETRY

DOCUMENTATION

TURN ON PROCEDURE

• First step turn on power keys

• Second step turn on the control cabinet key (Make it horizontal).

• Third step turn on IRM (In-Room

Monitor)

• Fourth step turn on 4D Console

MACHANICAL CHECKS

• Rotate gantry & Collimator at 0 degree.

• Then turn on HyperTerminal MLC.

• Check Couch movement(LAT,LNG,VRT) and Breaks manually and motorized. • Check all safety measures.

• Check ODI (optical density indicator) with the help of front pointer array set on 100 cm

• ODI exact set on 100 cm SSD on couch and both lateral laser should be touch the edges of couch.

• Field size should be set on 20x20 at 100 cm SSD on Field Card.

• Check water temperature , system pressure, SF 6(Sulfur Hexafluoride) gas pressure and water level . These value enter online in Morning checkout .

• Insert accessory mount at gantry then insert applicator size 15x15 with cutout tray. warm-up machine .We have five electron energies 6MeV,9MeV,12MeV,15MeV, 18MeV all electron energies run during Morning QA.

WARMUP PROCEDURE

• We have two photon energies 6MV and 18MV photon run during Morning QA for Warm-Up machine.

• We are check beam interlocks, and beam indicator lights on daily Morning QA. we have some checks of beam interlock's .

Key turn on and turn off Beam off button Backup counter LPO button Door interlock

• We have some parameters apply during Morning QA on checkmate 2 phantom.

Checkmate2 set on central axis. Field size should be set on 15x15 Gant.0

coll.0 SSD set on 122cm. We get some references value during dosimetry 6MV 18MV photon and 6MeV electron on daily basis. Checkmate 2 phantom have 8 channels (A2,A3,A4,A5,A6,A7,A7) each channel

calibrate to each energy

Exp: A2 calibrate for 6MV, A3 calibrate for 18MV. One is calibrate for electron day by day.

PARAMETERS & PROTOCOL

NOTE: Deliver 100 MUs, the electrometer reading should be within 98%≤ CPD ≤ 102%, tolerance level is ±2% . If there are unusual observation or reading are beyond the tolerance then consult Physicist before treating the patients.

DOCUMENTATION

• We have a QA sheet after QA we taken values documented in QA sheet. With two RTT Signature