© 2014 Halliburton. All rights reserved. DID YOU KNOW HEARING PROTECTION BLOCKS NOISE FROM REACHING YOUR EARDRUM BY FORMING AN AIRTIGHT SEAL.  Do not wear hats underneath muff -style hearing protectors.  Foam - and insert -style hearing protectors must be fully inserted into the hearing canal to be effective.  Extremely noisy work environments may require wearing both foam -style plugs and a muff -style hearing protector. Bypassing Safety Controls The Halliburton Life Rules are a set of core factors that affect personal safety that all Halliburton employees know and live by. These are key components for identifying and managing the hazards in our business.