This document outlines the daily quality assurance procedure for a linear accelerator. It describes turning on the machine, performing mechanical checks like gantry and couch movement tests, warming up the machine using various electron and photon energies, and performing dosimetry measurements to ensure parameters are within tolerance levels. Results are documented in a QA sheet for record keeping. The purpose is to ensure consistent machine quality and patient safety by verifying proper dose delivery and checking for any mechanical or software errors.
2. 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.
4. 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
5. 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.
6. 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.
7. 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
8. 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
9. 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 賊2% . If there are unusual observation or reading are beyond the
tolerance then consult Physicist before treating the patients.
10. DOCUMENTATION
We have a QA sheet after QA we taken values
documented in QA sheet. With two RTT Signature