Home · Environment & Health

🌡️ Environment & Occupational-Health Tools

Three calculators for the physical-agent exposures hardest to manage in the Gulf: noise, heat and vibration. Standards-aligned, instant verdict, printable.

41Noise Dose (LAeq, Daily Exposure)

Computes L_EX,8h (8-hour normalised exposure) and the OSHA noise dose %. OSHA 1910.95 PEL = 90 dBA TWA (5 dB exchange rate). ACGIH / EU = 85 dBA TWA (3 dB exchange rate).

Sound level L_A (dBA)

Exposure duration (hours)

Criterion / exchange rate

Hearing protector NRR (dB) — optionalOSHA derates NRR by 50% in field use.

Result

— dBA L_EX,8h

—

Effective level at ear—

Dose—

Action level—

PEL—

42WBGT Heat Stress (ISO 7243:2017)

Computes the Wet-Bulb Globe Temperature and the ACGIH TLV-Heat work/rest cycle for the given metabolic rate. Outdoor: WBGT = 0.7·T_w + 0.2·T_g + 0.1·T_a. Indoor / no solar: WBGT = 0.7·T_w + 0.3·T_g.

Wet-bulb T_w (°C)

Globe T_g (°C)

Dry-bulb T_a (°C)

Environment

Workload

Acclimatised?

Result

— °C WBGT

—

TLV limit (acclimatised)—

Recommended work/rest—

Water intake (light/mod/heavy)—

Reference: ISO 7243:2017, ACGIH TLV-Heat Stress (2024). Unacclimatised workers: reduce work by 50% on day 1, +20% per acclimatisation day.

43Hand-Arm Vibration A(8)

Daily 8-hour vibration exposure: A(8) = a_hv · √(T/8). ISO 5349-1. EU Action Value = 2.5 m/s², Limit Value = 5.0 m/s². Above ELV, exposure must stop.

Tool vibration magnitude a_hv (m/s²)From tool datasheet — typical impact drill 9, chipping hammer 18, grinder 4.

Daily trigger time T (hours)

Use anti-vibration gloves? Gloves reduce 10–30% in mid-band; do not assume more.

Result

— m/s² A(8)

—

Effective magnitude—

EU Action Value (EAV)2.5 m/s² A(8)

EU Exposure Limit (ELV)5.0 m/s² A(8)

Points (HSE scale, 100 = EAV)—

Reference: ISO 5349-1:2001, EU Directive 2002/44/EC. Above ELV: stop and engineer the task.