| OEL | occupational exposure limit |
|---|---|
| PE | Edinburgh Pharmacopoeia; pancreatic extract; paper electrophoresis; partial epilepsy; pelvic examina... |
| PEL | peritoneal exudate lymphocyte; permissible exposure limit |
| REG | radiation exposure guide; radioencephalogram, radioencephalography |
| REL | rate of energy loss; recommended exposure limit; resting expiratory level |