PHYSICAL PRINCIPLES OF ULTRASOUND

ULTRASOUND AS A WAVE

Sound is propagated through a medium (e.g. air) as a mechanical vibration of the particles of that medium and in simple terms may be categorised by its loudness and pitch or frequency. “Ultra” means beyond, ultrasound is sound with a frequency beyond that of human perception (i.e. >20 kHz), and has the same physical properties as “audio” sound. Most clinical diagnostic applications of ultrasound employ frequencies in the range 2 - 10 MHz.

Ultrasonic energy travels through a medium in the form of a wave. Although a number of different wave modes are possible, in almost all diagnostic applications, ultrasound propagates in the form of a longitudinal wave, where the particles of the medium oscillate in the direction of propagation of the sound. Energy is transferred through the medium in a direction parallel to that of the oscillations of the particles. The particles themselves do not move through the medium. They simply vibrate to and fro about their mean position.

The vibrations of individual particles may be complex For simplicity consider the movement of a single particle excited by pure sinusoidal continuous wave.

KOMPETENSI PROFESIONAL KEPALA LABORATORIUM, TEKNISI LABORATORIUM DAN LABORAN LABORATORIUM SEKOLAH/MADRASAH (Salah Satu Kompetensi Tenaga Laboratorium Sekolah/Madrasah menurut Permendiknas RI No. 26 tahun 2008)

KEPALA LABORATORIUM

4. Kompetensi Profesional 4.1 Menerapkan gagasan, teori, dan prinsip kegiatan laboratorium sekolah/madrasah 4.1.1 Mengikuti perkembangan pemikiran tentang pemanfaatan kegiatan laboratorium sebagai wahana pendidikan
4.1.2 Menerapkan hasil inovasi atau kajian laboratorium
4.2 Memanfaatkan laboratorium untuk kepentingan pendidikan dan penelitian di sekolah/madrasah
4.2.1 Menyusun panduan/penuntun (manual) praktikum
4.2.2 Merancang kegiatan laboratorium untuk pendidikan dan penelitian
4.2.3 Melaksanakan kegiatan laboratorium untuk kepentingan pendidikan dan penelitian
4.2.4 Mempublikasikan karya tulis ilmiah hasil kajian/inovasi

4.3 Menjaga kesehatan dan keselamatan kerja di laboratorium sekolah/madrasah


4.3.1 Menetapkan ketentuan mengenai kesehatan dan keselamatan kerja
4.3.2 Menerapkan ketentuan mengenai kesehatan dan keselamatan kerja
4.3.3 Menerapkan prosedur penanganan bahan berbahaya dan beracun
4.3.4 Memantau bahan berbahaya dan beracun, serta peralatan keselamatan kerja