What is kerma area product?

Kerma-Area Product. The KAP is simply average the air kerma (in Gy) multiplied by the corresponding x- ray beam cross-sectional area (in cm2), the product of which being expressed as Gy ⋅ cm2 [5].

What is DAP measured in?

Dose Area Product (DAP) meters which measure in units of [Gy*m(2)], are widely used in radiology, fluoroscopy and interventional cardiology X-ray units. However, assessment of the radiological hazard to the patient undergoing a given diagnostic procedure cannot be readily obtained from the measured value of DAP.

How do you calculate DAP?


  1. Measured dose @ 1 m from the X-ray source:
  2. Size of irradiated area @ 1 m from the X-ray source:
  3. DAP = 0.002 Gy ∙ 400 cm2 = 0.8 Gycm2.

What is DAP in fluoroscopy?

The dose area product (DAP) or kerma area product (KAP) is a method of radiation dose monitoring used in radiographic and fluoroscopic studies. It provides an indication of the radiation dose received by a patient.

What is kerma used for?

Kerma measures the amount of energy that is transferred from photons to electrons per unit mass at a certain position. Absorbed dose, on the other hand, measures the energy deposited in a unit mass at a certain position. At radiological energies, transfer and deposition of energy is virtually equal.

What does kerma stand for?

kinetic energy released in materials
Acronym for kinetic energy released in materials. Kerma is the sum of the initial kinetic energies of all the charged particles liberated by uncharged ionizing radiation (neutrons and photons) in a sample of matter, divided by the mass of the sample.

Why is DAP recorded?

The dose area product (DAP) is used in assessing the radiation risk from diagnostic X-ray and interventional procedures. The DAP is a surrogate measurement for the total amount of X-ray energy delivered to the patient, and reflects the dose within the radiation field and area of tissue irradiated.

How does a DAP meter work?

How DAP is measured. An ionization chamber is placed beyond the X-ray collimators and must intercept the entire X-ray field for an accurate reading. Different parameters of the X-ray set, such as peak voltage (kVp), tube current (mA), exposure time, or the area of the field, can also be changed.

What DAP means?

How Delivered-at-Place (DAP) Works. Delivered-at-place simply means that the seller takes on all the risks and costs of delivering goods to an agreed-upon location. This means the seller is responsible for everything, including packaging, documentation, export approval, loading charges, and ultimate delivery.

How does DAP meter work?

The dose area product (DAP) meter is an instrument mounted on the X-ray tube, which accurately mea- sures the radiation emitted from the source after calibration. This study determined the correlation between radiation doses absorbed by health care workers and DAP measurements at Universitas Hospital, Bloemfontein.

How many mGy is safe?

A dose of ~3,000 mGy produces an acute gastrointestinal syndrome that can be fatal without major medical intervention, and a dose of ~ 5,000 mGy is considered the human LD 50 / 30, that is, the lethal dose for 50% of the population in 30 days, even with treatment.

What made kerma famous?

Kerma is one of the largest archaeological sites in ancient Nubia. It has produced decades of extensive excavations and research, including thousands of graves and tombs and the residential quarters of the main city surrounding the Western/Lower Deffufa. Around 3000 BC, a cultural tradition began around Kerma.