Analisis faktor risiko low back pain pada aktivitas manual lifting pada aspek load weight, horizontal location, vertical location, vertical distance location, distance location, posture, couling, frequency, dan duration di bagian produksi PT. Kembar Jaya Kabupaten Tegal = Analysis the risk factor of low back pain injury on manual lifting activity from aspek load weight, horizontal location, vertical location, vertical distance location, distance location, posture, couling, frequency, and duration in PT. Kembar Jaya Kabupaten Tegal