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How loud was a Space Shuttle launch?

142–155dB maxinside the orbiter payload bay (142 dB) and about 67 m from a single booster on a static test stand (155 dB)

NASA's water sound suppression system brought the acoustic level inside the Space Shuttle's payload bay down to about 142 dB at liftoff, under a 145 dB design limit. In static tests, a single Shuttle solid rocket booster measured 155 dB about 67 m away and over 140 dB at 300 m.

Level
142–155 dB maxunweighted maximum sound level
Daily limit
No safe unprotected exposureNIOSH, at the loud end

What the numbers mean

How it was measured. Two NASA figures under different conditions: about 142 dB inside the payload bay at liftoff with the water sound suppression system running, and 155 dB overall sound pressure level measured about 67 m from one Reusable Solid Rocket Motor during a horizontal static firing. Unweighted (overall) levels.

The noise of a Shuttle launch was a structural problem, not just a spectator experience: sound reflected off the launch platform could damage the orbiter and its cargo. NASA installed a sound suppression system on the pads and the mobile launcher platform for this reason. Nine seconds after liftoff its flow peaked at 900,000 gallons per minute, and NASA says it reduced acoustic levels in the payload bay to about 142 dB, below the 145 dB design requirement.

The two solid rocket boosters were the main noise source. NASA Marshall, Wyle Labs and ATK measured one Shuttle Reusable Solid Rocket Motor during horizontal static firings: about 67 m off the nozzle centreline and 70 m downstream, the overall sound pressure level was 155 dB, and peak overall levels in the far field were over 140 dB at 300 m. A launch puts two of these boosters alongside the main engines, so these test figures are a guide to scale rather than a measurement of a full launch.

Water is still used for the same job. Kent Gee of BYU writes that flooding the launch platform typically reduces rocket noise by 3 to 5 dB by absorbing sound in bubbles and turning it into heat.

How long is safe?

At 155 dB the level is above 140 dB, where harm can be immediate.

LevelNIOSH limit (85 dBA, 3 dB rule)OSHA limit (90 dBA, 5 dB rule)UK/EU 80 dB(A) action value reached afterUK/EU 85 dB(A) action value reached after
142 dB maxunder 1 s21 sunder 1 sunder 1 s
155 dB maxunder 1 s4 sunder 1 sunder 1 s

Times are for a whole day’s exposure, with the rest of the day quiet. The workplace limits were written for adults at work, not for children. Work out a mixed day with the noise dose calculator.

Protecting your hearing

Public viewing for Shuttle launches was miles from the pad. For any large rocket launch, earplugs or earmuffs are worth carrying; children feel the low-frequency rumble strongly.

Earplug and earmuff ratings (NRR in the US, SNR in the UK and EU) are lab figures; real-world protection is usually lower. How to read the ratings.

Compared with sounds nearby

Using midpoints of each range. Energy multiplies by 10 every 10 dB; perceived loudness roughly doubles (why).

  • SLS rocket launch (Artemis I) (127–136 dB max): this has about 50× its sound energy and sounds about 3.2× as loud.
  • Chrysler air raid siren (137–138 dB): this has about 13× its sound energy and sounds about 2.1× as loud.
  • Saturn V launch (170–175 dB max): it has about 251× the sound energy of this and sounds about 5.3× as loud.
  • Loudest car stereo (181–184.9 dB max): it has about 2,786× the sound energy of this and sounds about 10.9× as loud.

Questions

Why did NASA spray water during Shuttle launches?

To protect the orbiter and its payloads from acoustic energy reflected off the launch platform. The system reduced payload bay levels to about 142 dB, below a 145 dB design limit.

How loud was a Shuttle solid rocket booster?

In a static test, one booster measured 155 dB about 67 m away and over 140 dB at 300 m.

Sources

  1. Sound Suppression System, NASA (Wayback Machine copy). Supports: dB_low: 142 dB in payload bay.The system reduces acoustical levels within the orbiter payload bay to about 142 decibels, below the design requirement of 145 decibelsChecked 2026-11-02.
  2. Sound Suppression System, NASA (Wayback Machine copy). Supports: Water flow rate.Nine seconds after liftoff, peak flow rate is 900,000 gallons per minuteChecked 2026-11-02.
  3. Measurement and Characterization of Space Shuttle Solid Rocket Motor Plume Acoustics, NASA Technical Reports Server. Supports: dB_high: 155 dB at about 67 m (static firing).At approximately 67 m off nozzle centerline and 70 m downstream of the nozzle exit plan, the measured overall sound pressure level of the RSRM was 155 dBChecked 2026-11-02.
  4. Measurement and Characterization of Space Shuttle Solid Rocket Motor Plume Acoustics, NASA Technical Reports Server. Supports: Over 140 dB at 300 m.Peak overall levels in the far field were over 140 dB at 300 m and 50-deg off of the RSRM thrust centerlineChecked 2026-11-02.
  5. The roar of a rocket, Physics Today (Kent L. Gee). Supports: Water reduces noise 3 to 5 dB.The inundation typically reduces the noise by 3–5 dB (50–70%) by absorbing sound via bubblesChecked 2026-11-02.

This page is general information, not medical advice. If you have ringing in your ears, muffled hearing or any change in your hearing, see an audiologist or your doctor.