4.—(1) The lower exposure action values are—
(a)a daily or weekly personal noise exposure of 80 dB (A-weighted); and
(b)a peak sound pressure or 135 dB (C-weighted).
(2) The upper exposure action values are—
(a)a daily or weekly personal noise exposure of 85 dB (A-weighted); and
(b)a peak sound pressure of 137 dB (C-weighted).
(3) The exposure limit values are—
(a)a daily or weekly personal noise exposure of 87 dB (A-weighted); and
(b)a peak sound pressure of 140 dB (C-weighted).
(4) Where the exposure of an employee to noise varies markedly from day to day, an employer may use weekly personal noise exposure in place of daily personal noise exposure for the purpose of compliance with these Regulations.
(5) In applying the exposure limit values in paragraph (3), but not in applying the lower and upper exposure action values in paragraphs (1) and (2), account shall be taken of the protection given to the employee by any personal hearing protectors provided by the employer in accordance with regulation 7(2).