The Science Behind Industrial Noise Control

• SONEX One Baffles
• Industrial Noise Control Products
• SONEX Curtain Enclosure System
• PROSPEC Composite

How to Make Noisy Facilities More Comfortable and Productive

In manufacturing plants and warehouses, excessive industrial noise can erode productivity, jeopardize hearing and reduce speech intelligibility across workspaces. That’s why industrial noise control is a critical discipline, blending the physics of sound with clever design to transform loud factories or workshops into more workable environments.

Understanding Sound: Pressure, Frequency and Reflection

To address industrial noise control effectively, you first need to understand how sound works.

• Sound is vibration in air. Whether it’s a machine motor, a pneumatic press or a cooling fan, the source vibrates, creating waves in the air that propagate outward.
• Decibels (dB) track loudness. 0 dB is near silence; ~130 dB is a threshold of pain. Importantly, two sounds with the same dB can differ dramatically in how they feel — because their frequency content can vary.
• Frequency matters. The human ear hears from ~16 Hz up to ~20,000 Hz. Speech intelligibility tends to live in the 600–4800 Hz band, while low-frequency noise is harder to block.  
• Reflections lead to echo and reverberation. In rooms with hard surfaces (steel, glass, concrete), sound bounces and lingers. This is quantified by the reverberation time — the time it takes for sound to decay by 60 dB (or down to one-millionth of its original energy).

When you don’t manage reflection and residual energy, noise builds up. Machinery noise might not only compete with itself but also degrade clarity for human operators.

Absorption, Sabins and Reverberation Time: The Core Tools of Industrial Noise Control

Fundamental metrics and methods that are ready-made for industrial settings:

• Absorption coefficient. When sound hits a surface, part of it is reflected and a portion is absorbed (dissipated). The absorption coefficient (α) measures the fraction absorbed. For example, painted concrete might have α ≈ 0.06; acoustic panels might reach α of 0.6 or more depending on thickness and design. s
• Sabins as units of absorption. A sabin is a unit of sound absorption. Roughly, one sabin represents one square foot of perfectly absorbing surface. Real-world materials deliver fractional sabins (e.g. 0.5 sabins per ft²).
• Reverberation equations. If you multiply the room’s volume (cubic feet) by its total absorption, and then apply standard acoustic formulas, you can predict or design for target reverberation times.
• Diminishing returns. Adding more acoustical material does reduce noise, but after a point, additional material yields smaller incremental improvements.

In industrial environments, understanding these relationships is vital. You can’t just blanket every surface. You must prioritize and strategically place acoustic treatments.

Here are actionable strategies:

1. Treat the Room Don’t just target the machine — treat the acoustics of the space.

• Use curtain enclosures, acoustical barrier materials, acoustic panels, baffles or ceiling tiles to absorb reflections on walls, ceilings and even hanging structures.
• In many cases, reductions of 4–6 dB (20–30 % perceived reduction) are achievable with moderate coverage. 

In a loud production facility, reverberation from floors and high ceilings can amplify noise. Adding treatment to surfaces — not just near machines — can dramatically improve clarity and lower overall sound levels.

2. Barrier or Shielding Solutions

When machinery produces high-level noise, you may need to block direct paths:

• Barriers or screens can be placed between noise source and receiver. PROSPEC composites combines absorption and isolation.
• Barriers work best when placed close to either the source or the receiver, reducing the direct sound proportion.

In a factory line scenario, adding a transparent barrier between a station and a walkway can help reduce worker exposure without interfering with line-of-sight.

3. Enclosures Around Machines

Where possible, wrap noisy equipment in dedicated acoustic enclosures:

• Enclosures limit sound at the source. For mechanical rooms or critical machinery (compressors, pumps, 

This is often the gold standard: control the problem at its root. In heavy industrial settings, the delta achieved by enclosures can outpace surface treatments alone.

 

4. Focused Treatment Near the Noise Source

Not all surfaces matter equally. 

• Treating the wall nearest the noise source can cut 2–6 dB, often at low cost. 
• Placement matters: targeting critical reflection paths yields more efficient gains than blanket treatment.

In many factories, machinery is backed by a wall — placing absorption there mitigates intense reflections bouncing back into working zones.

Applying Industrial Noise Control in Real Settings

Here’s a simplified approach for industrial facilities:

1. Measure baseline noise. Use sound level meters and frequency analysis to identify troublesome bands.
2. Estimate room absorption. Tally up floor, wall, ceiling areas and their absorption coefficients to compute existing sabins.
3. Select target reverberation time or sound level. Based on room use (assembly, control room, office), choose an acoustical goal.
4. Calculate additional absorption required. Using reverberation formulas, determine how many sabins you need.
5. Prioritize treatments. Start with ceiling, main reflections, nearest wall to machine, then barrier and enclosures.
6. Implement and re-measure. Add treatments in stages, and re-check noise levels and speech intelligibility.

You may find that achieving a 4–6 dB reduction is easily accomplished. For more noise reductions, you’ll need aggressive measures — more coverage, better materials or complete enclosures.

 Why Industrial Noise Control Matters

• Worker Health & Safety. Chronic exposure to high noise is linked to hearing loss, fatigue, communication errors and elevated stress.
• Operational Efficiency. Improved acoustics can reduce errors in communication, boost concentration and improve facility usability.
• Regulatory Compliance. Many areas impose permissible exposure limits on noise in workplaces. Effective industrial noise control helps you stay within bounds.
• Perceived Quality & Morale. A quieter plant signals professionalism, care and investment in worker experience.