All 14 requirements for the Loudest Scream by a Crowd (Outdoors) record attempt.
View on GWR Website ↗This attempt must comply strictly with Guinness World Records guidelines. Read these carefully so you know what to expect on the day. Breaking any of these rules can invalidate the attempt.
The event must be held outdoors to eliminate room-reflected sounds.
"Screaming" is confined to the human voice only — no foot stomping, clapping, or noisemakers. It is at the discretion of Guinness World Records to recognise the sound as a scream.
Participants must number more than 10 to be considered a crowd. The total number of participants must be provided.
Participants may sit or stand for the attempt. The total number of participants must be provided.
The event must be held outdoors where sound reflections are suppressed. Early reflections in the venue must be reduced by at least 10 dB. Details of the chosen location must be provided.
Weather conditions should be free of precipitation and wind speeds must be below 6 m/s.
No mechanical aids or musical instruments are permitted unless specified. Any equipment that can amplify sound — including microphones and phones — must be switched off or removed from the attempt area. This must be verified by independent witnesses.
A loud start signal recognised by all participants must be used.
Sound level measurements must be expressed as an A-weighted Sound Pressure Level in decibels to the nearest 0.1 dB, with the highest peak reading recorded. The equivalent C-weighted Sound Pressure Level must also be provided.
Sound level must be measured on a Class 1 precision sound level meter in accordance with the latest ISO/EN/BSI/IEC standard (e.g. IEC 61672-1:2013), laboratory certified and calibrated within one year of the attempt. On-site calibration with a portable calibrator is encouraged.
The record must be measured by an independent, suitably qualified expert — such as a sound engineer or acoustic expert — in the presence of two independent witnesses. The expert must supply all equipment and provide their qualifications (e.g. IOA, ASA, or AES membership, or a relevant bachelor's degree).
The scream must maintain a high pitch above 2,000 Hz throughout the duration of the attempt. This must be measured and verified by the sound engineer.
The microphone must be connected to a computer via a professional quality recording interface and analysed in software capable of FFT (Fast Fourier Transform) analysis. Sampling frequency must be at least 44.1 kHz and an FFT size of at least 4,096 points.
Background noise must be measured as an A-weighted Equivalent Continuous Sound Pressure Level over 30 seconds within one minute of the attempt and must be below 60 dB. Spurious sounds make the attempt null and void. Photographic and/or video evidence of background noise must be provided.