A Message from Miami-Dade Limestone Products Association (M-DLPA) on COVID-19

Understanding Vibrations – MDLPA

Understanding Vibrations

What We Hear, Feel and What’s Actually Going On

Vibrations from nearby mining operations can be startling. But when it comes to measuring sound and vibration, it’s important to keep in perspective what we hear, feel and what’s actually going on.

Vibrations from nearby mining operations can be startling. But when it comes to measuring sound and vibration, it’s important to keep in perspective what we hear, feel and what’s actually going on.

graphic depicting different types of waves, including air waves, surfaces waves, and body waves

Feeling Vibrations Damage

As you can see from the chart, humans feel vibrations as low as .02 inches per second (in/s). That’s 1/25th of the safe, legal limit (0.5 in/s) used in Florida limestone mining operations, and 1/125th of the vibration levels caused by hammering a nail. If you’re feeling vibrations during or after a blast, don’t worry. Humans feel vibrations at very low levels, but those low-level vibrations can’t cause damage to homes. Blasting standards are specifically set to ensure that vibrations levels come nowhere close to the damage threshold.

Graphic showing typical blasting standards overlaid with common household vibration levels. Blasting yields a lower vibration level than wind at 20 mph or the vibration caused hammering nails.

Sound

Source: https://www.omicsonline.org/open-access/ground-vibrations-and-air-blast-effects-induced-by-blasting-in-open-pit-mines-case-of-metlaoui-mining-basin-southwestern-tunisia-2381-8719-1000247.php?aid=73743

Sound

chart comparing different sound levels with common household items. Blasting occurs at 110-120dB, whereas hammering nails and fireworks measure 130 and 165 dBs respectively. Studies show that there is no structural damage from sound levels below 180 dB

Source: https://www.omicsonline.org/open-access/ground-vibrations-and-air-blast-effects-induced-by-blasting-in-open-pit-mines-case-of-metlaoui-mining-basin-southwestern-tunisia-2381-8719-1000247.php?aid=73743

What you're feeling chart, displays what different people may feel from a blast at differing lengths. 96% of a blast's energy is spent inside of the blast area. The remaining 4-5% or less reaches us at levels too low to cause damage.

How Environmental Forces Affect Your Home

Everyday environmental forces like changes in temperature and humidity, soil pressure, wind events and thunderstorms are the most likely cause of stress to nearby homes (and unfortunately, natural forces can’t be regulated).

Takeaway

1. Everyday activities can reach and even exceed vibration and sound levels from nearby mining operations:
2. Humans feel vibrations at very low levels, but those low-level vibrations can’t cause damage to homes.
3. Everyday environmental forces are the most likely cause of stress to nearby homes: