The Control of Noise at Work Regulations 2005

Regulation 2(1)

SCHEDULE 1

PART 1 Daily Personal Noise Exposure Levels

1.  The daily personal noise exposure level, L_EP,d, which corresponds to L_EX,8h defined in international standard ISO 1999: 1990 clause 3.6, is expressed in decibels and is ascertained using the formula:

where—

• T_e is the duration of the person’s working day, in seconds;

• T₀ is 28,800 seconds (8 hours); and

• 

  is the equivalent continuous A-weighted sound pressure level, as defined in ISO 1999: 1990 clause 3.5, in decibels, that represents the sound the person is exposed to during the working day.

2.  If the work is such that the daily exposure consists of two or more periods with different sound levels, the daily personal noise exposure level (L_EP,d) for the combination of periods is ascertained using the formula:

where—

• n is the number of individual periods in the working day;

• T_i is the duration of period i;

• (L_Aeq,T)i is the equivalent continuous A-weighted sound pressure level that represents the sound the person is exposed to during period i; and

• 

  is equal to T_e, the duration of the person’s working day, in seconds.

Regulation 2(1)

PART 2 Weekly Personal Noise Exposure Levels

The weekly personal noise exposure, L_EP,w, which corresponds to

defined in international standard ISO 1999: 1990 clause 3.6 (note 2) for a nominal week of five working days, is expressed in decibels and is ascertained using the formula:

where—

• m is the number of working days on which the person is exposed to noise during a week; and

• (L_EP,d)_i is the L_EP,d for working day i.