Radiation Therapy
VeriDose
®
Solid-State
Diode Detectors
Nuclear Associates Model 30-471
•
Designed to provide superior
response, reliability, and
performance
•
Long-lifetime diodes. Tested to
2 x 10
6
cGy in a high-energy
electron beam, the most damaging
radiation
•
Very low dose rate and temperature
dependence
•
Hemispherical shape improves
isotropic response and reduces
angular and field-size
dependencies
Introduction
Using the VeriDose Patient Dose Monitor Quality Control (PDMQC) System or the
VeriDose V Patient Dose Monitor in conjunction with VeriDose Solid-State Diode
Detectors, you can verify the given dose quickly and accurately during treatment,
thus avoiding potential misadministration of radiation.
Applications
VeriDose Solid-State Diode Detectors are solid-state silicon-based radiation detectors
that utilize a p-n junction. These rugged diodes are encased within a biocompatible
polystyrene material. A low noise coaxial cable is used to connect the diode to an
electrometer. When attached to an electrometer, these diodes provide enhanced
sensitivity and instantaneous response time.
Features
• Waterproof design with appropriate buildup
for all clinical photon and electron energies
Flat bottom permits secure, easy placement
on the patient
Color-coded for ease of identification
Dose rate independent
Responds to photons and electrons
Responds to dose rates of 1.0 to 1000 cGy/min
Can be used on continuous (
60
Co) x-ray
beams, pulsed (linear-accelerator) x-ray
beams, and electron beams
Optimized for use with all Nuclear Associates’
Patient Dose Monitors and high-quality
medical-grade ionization chamber
electrometers
All diodes are supplied with a non-crimp
repairable cable with a coax BNC connector
Specifications
Photon and electron diode detectors
Nominal sensitivity
1.5 nC/cGy
Sensitivity volume
0.25 mm
3
Output polarity
Positive/Negative
Linearity
< 0.1% for dose ranges from 0.01 to
10 Gy; < 0.1% for dose rates 3 to 5 Gy/min
Reproducibility
0.2%
Angular dependence
< 2% ± 60° for lower energy
diodes (Models 30-471 &
30-472); < 2% ± 10°; < 5%
± 60° (for higher energy
photon diodes and electron
diodes)
Sensitivity loss at
10 kGy
< 15%
Cable length
10 ft (3 m)
Dimensions
8 mm Ø
Weight
42 gm
Optional accessories
Diode Extension Cable
, 30 ft (9 m)
(Model 88-490)
Diode Extension Cable
, 10 ft (3 m)
(Model 88-490-1000)
Available model(s)
Model
Range
Polarity/Color
Buildup
type
Buildup
(g/cm2)
Electrometer
30-471
1-4 MV
Positive/Blue
Cu
0.732
37-720
30-471-8000
1-4 MV
Negative/Blue
37-705
30-472
5-11 MV
Positive/Yellow
Cu
1.359
37-720
30-472-8000 5-11 MV Negative/Yellow
37-705
Tested.
Meets applicable standards.
30-473
12-17 MV
Positive/Red
W
2.606
37-720
30-473-8000 12-17 MV
Negative/Red
37-705
30-474
18-25 MV
Positive/Green
W
3.574
37-720
30-474-8000 18-25 MV Negative/Green
37-705
30-475
5-25 MeV
Positive/Grey
0.284
37-720
30-475-8000 5-25 MeV
Negative/Grey
37-705
