Millions of workers face hearing hazards annually across industries like construction, manufacturing and warehousing. To help reduce workplace noise, employers should start with administrative and engineering controls like relocating loud equipment or using quieter tools. If the workplace is louder than 85 decibels on average over eight hours, however, OSHA also requires employers to provide hearing protection and establish a hearing conservation program.

Hearing protection devices (HPDs) fall into two main categories: active and passive. Use the following guide to understand the key differences between active and passive protection, the variations within each category and the important features to consider.

Understanding Active vs. Passive Devices

Active devices, or electronic hearing protection, use digital components to suppress surrounding noises while allowing the user to hear normally. Passive devices, like earplugs, act as barriers blocking or absorbing noise without electronics.

Types of Noise Reduction

There are three main types of noise reduction technologies used in HPDs:

Conventional Attenuation: This type provides the same level of noise reduction regardless of the noise level to help provide consistent protection throughout the day.

Level-Dependent Attenuation: Noise reduction varies based on the noise level and can be passive (non-electronic) or active (electronic). It offers protection from high, variable noise conditions and impulse noises from pneumatic tools or arc flashes.

Flat or Uniform Attenuation: This type helps reduce low and high-frequency sounds by maintaining a more natural sound quality. It can be useful for employees with lower noise exposures and is often used by musicians.

How Does Active Noise-Cancelling Technology Work?

Active hearing protection uses electronic components that continuously monitor the surrounding environment for loud sounds. When a sudden increase in noise is detected, internal mechanisms help reduce the intensity of the sound before it reaches the ears. This real-time adjustment effectively protects against damaging sounds without compromising the user’s ability to hear softer sounds in their environment.

Active Hearing Protection: Electronic Earmuffs, Earplugs & Communication Headsets 

One common example of active hearing protection is the electronic earmuff. These earmuffs typically feature built-in microphones that pick up ambient sounds and speakers that deliver them to the user at a safe volume. When a loud noise is detected, the electronic system instantaneously dampens the sound, preventing it from reaching harmful levels. They are particularly useful in environments where workers need to communicate and remain aware of their surroundings while still being protected from sudden loud noises.

Over-the-head electronic earmuffs are frequently worn when hard hats and face shields aren’t required. Active noise-suppressing technology can also be turned off. Additionally, noise-reducing communication headsets and electronic earplugs help workers stay in touch while protecting their hearing in loud environments. These devices connect to radios or communication tools, allowing hands-free communication and privacy during conversations.

Passive Hearing Protection: Foam Earplugs and Earmuffs

Passive protection relies on physical materials to block or absorb sound. Foam earplugs, for example, are designed to fit snugly into the ear canal, creating a barrier that helps reduce surrounding noise. Similarly, earmuffs use sound-absorbing materials to block and decrease noise. Many styles of earmuffs are available, from hard-hat mounted and over-the-head to behind-the-neck to help keep workers comfortable when additional PPE equipment like face shields and respirators need to be worn.

Considerations When Choosing Hearing Protection

Performing a risk assessment of the existing noise hazard in your workplace is a critical first step to help you determine the right ear protection for your work environment. Evaluate your workplace according to the following factors:

Noise Level and Frequency: Consider the specific noise levels and frequencies encountered in the work environment. Active protection is best for scenarios where sudden loud noises are prevalent, while passive protection is suitable for consistent, lower-level noise.

Protection Type: Determine the type of hearing protection needed. General-purpose hearing protection devices focus solely on hearing protection, using sound-absorbing materials without additional features. Electrically insulated devices are designed to prevent arcing near live electrical circuits by using non-conductive materials or coatings.

Communication Needs: Evaluate the necessity of on-the-job communication. With its ability to amplify ambient sounds and connect to phones and radios, active protection is important in environments where verbal communication is critical to worker safety.

Comfort and Fit: Both active and passive protection options come in various designs and sizes to fit the unique shape of each person’s ears. Comfort and proper fit are essential for effective noise reduction. Occupational Health & Safety notes that even a small gap between the earplug and the ear canal can significantly reduce the noise reduction provided, despite a high Noise Reduction Rating (NRR) indicated on the packaging.

Battery Life and Maintenance: It’s important to consider battery life and maintenance requirements for electronic earmuffs and other active protection devices. Ensuring the battery life lasts over extended periods is important for optimal safety.

Regulatory Compliance: Get to know the OSHA regulations and standards regarding hearing protection. Following the standards helps ensure your hearing protection meets the necessary safety requirements for your specific work environment.

Ultimately, the choice between active and passive hearing protection boils down to the specific demands of the work environment and worker preferences. Understanding the differences can help you make informed decisions and contribute to a safer workplace. Use the chart below to help compare the types of hearing protection.