Hearing protectors

Irrespective of the level of noise, the German Occupational Health and Safety Act (ArbSchG) states that exposure to noise at workplaces must be avoided or reduced to the greatest possible extent. The state of the art serves here as the point of reference. If one of the upper action values of the German Noise and Vibrations Occupational Safety and Health Ordinance (LärmVibrationsArbSchV) is violated, the employer must draw up and implement a programme of technical and organizational noise control measures.

If noise exposure cannot be avoided, suitable hearing protectors must be selected. The LärmVibrationsArbSchV requires the employer to make suitable hearing protectors available to his employees when the lower exposure action values are exceeded (L_EX,8h > 80 dB(A) and L_pC,peak > 135 dB(C)). Once the upper action values are reached, the use of hearing protection as specified is a requirement (L_EX,8h ≥ 85 dB(A) and L_pC,peak ≥ 137 dB(C)).

Hearing protectors must be selected so that the limits for the permissible exposure at the user's ear are observed taking account of the sound attenuation of the hearing protector. For the residual level L’ at the ear, the following therefore apply: L’_EX,8h ≤ 85 dB(A) and L’_pC,peak ≤ 137 dB(C). The HML check is used as standard in Germany for calculation of the residual level at the ear. It must first be determined whether the noise at the workplace is generally of high or medium frequency (HM class) or low frequency (L class). Either the M value or the L value of the hearing protector is used accordingly as the attenuation value.

In addition, correction values for use in the field (de-rating) must be applied. These take account of the fact that the sound attenuation values measured during type examination of the hearing protector are not generally reached under industrial conditions. Besides ageing and soiling of the products, a particular reason for this is incorrect or careless fitting and/or wearing of the hearing protectors.

More detailed information on the HML check and correction values for use in the field can be found in DGUV Rule 112-194 (formerly: BGR/GUV-R 194) and DGUV Informative publication 212-024 (formerly: BGI/GUV-I 5024). This selection method also forms the basis for the IFA selection program (see below) and the IFA list of approved products found in DGUV Rule 112-194.

For earplugs that are custom-moulded to the wearer's own ear canal, both the DGUV publications and the state TRLV technical rules governing noise under the German Noise and Vibrations Occupational Safety and Health Ordinance (LärmVibrationsArbSchV, Section 6.2.3) require a function check to be performed following delivery (within six months) and thereafter at regular intervals of no more than three years. Correct fitting of the custom-moulded earplug, and thus also the sound attenuation determined in the type examination and documented in the user information for the product concerned, cannot otherwise be assured for the individual user. Comprehensive information on this topic can be found in the information module provided by the Hearing protection subcommittee within the DGUV's Personal protective equipment expert committee (download module (PDF, 56 kB, non-accessible) ).

The most important information concerning the selection and use of hearing protectors can be found in DGUV Informative publication 212-024 on hearing protection. A more detailed description can be found in DGUV Rule 112-194 concerning the use of hearing protectors. These publications can be found at www.dguv.de/publikationen.

Documents and publications are also made available by the Hearing protectors subcommittee within the DGUV's Personal protective equipment expert committee and can also be accessed through the hearing protectors web app.They particularly include the guidelines for prevention, which provide even more detailed information on certain topics.

Two PC-based selection programs are available for download from the IFA. The exposure to noise and further characteristics of the workplace (such as a high dust load or the requirement of signal audibility) can be input into a general program which then creates a list of suitable hearing protection products. The second program is intended specifically for musicians. Besides assisting in selection of hearing protectors that are particularly suitable for this occupational group, it contains a module for calculating the actual noise exposure over a week.

Some working areas are subject to specific requirements concerning the signal audibility when hearing protectors are worn. Further information on this aspect can be found under Signal audibility when hearing protectors are worn.

As of 21 April 2019, manufacturers may place personal protective equipment (PPE) on the market only if it satisfies Regulation (EU) 2016/425 (PPE Regulation) (refer also to the IFA's specialist information on the subject of PPE). The PPE Regulation reclassifies hearing protectors as category III PPE. This category covers PPE against lethal hazards and irreversible damage to health. Category III PPE is subject to stricter safety requirements. This has consequences for both manufacturers (see below) and users. Manufacturers are particularly affected by the new requirement for supervision of the production process.

For a specified transition period, "category II PPE" and "category III PPE" hearing protectors will both be available on the market at the same time. The latter can be identified by the identification number of the notified body supervising production. This number must be applied by the manufacturer in addition to the CE marking.

Users are subject to the following new requirement: when an item of category III PPE is used, instruction including practical training must be conducted for the individuals using it. This is set out in DGUV Regulation 1, Section 31, which applies to PPE intended to provide protection against lethal hazards or irreversible damage to health.

Instruction is to be provided once a year. Model documents and recommendations concerning the nature and scope of the practical training are in preparation. Information can be found in Annex 6 of DGUV Rule 112-194 (concerning the mandatory instruction to be provided in the competent use of hearing protectors). This DGUV Rule describes topics and aspects that may be critical during the use of hearing protectors and may potentially reduce their protective action. The proper insertion of foam earplugs, in particular, requires care and training. This is precisely the purpose of instruction in the use of category III PPE. Annual instruction and accompanying drills in accordance with DGUV Regulation 1 are however not synonymous with competent use in the sense of Annex 6 of DGUV Rule 112-194 and Part 3, Section 6.3.3 of the TRLV technical rules governing noise. Where the product is used competently in this sense, the correction values for field use need not be applied, since it is assumed that careful insertion ensures that the sound attenuation values attained in the type examination are also attained in practice. For this purpose however, the relevant drills must be conducted four times each year, and documented. Part 3 of the TRLV technical rules governing noise stipulates this procedure for daily noise exposure levels of 110 dB(A) and above. Owing to the associated overhead, its use should be limited to such extreme cases.

Hearing protectors constitute category II personal protective equipment in accordance with EU Directive 89/686/EEC and may be placed on the market only when accompanied by an EC type-examination certificate. As of 21 April 2018, the new Regulation (EU) 2016/425 must be applied for type examination. Under this regulation, hearing protectors constitute category III PPE and require annual supervision of production in accordance with Module C2 (Annex VII) or Module D (Annex VIII) in addition to an EU type-examination (Module B, Annex V). The IFA is an accredited and notified test and certification body within DGUV Test for hearing protectors. It performs type examinations and issues EC/EU type-examination certificates. The manufacturing company confirms that its product complies with EU Directive 89/686/EEC or Regulation (EU) 2016/42 as applicable by applying the CE marking and issuing its declaration of conformity. For products approved under the new PPE Regulation, CE marking must be accompanied by the identification number of the notified body supervising production.

EC type-examination certificates issued under Directive 89/686/EEC remain valid until 20 April 2023 unless they expire or otherwise become invalid before that date. These certificates may also be used to place hearing protectors (or other PPE) on the market after 20 April 2019 when the product satisfies all other aspects of Regulation (EU) 2016/425. This transitional arrangement obviates the need for all existing EC type-examination certificates to be re-issued as EU type examination certificates within one year.

As of 21 April 2018, the IFA will be able to issue only EU type examination certificates in accordance with Regulation (EU) 2016/425. Type examination for such products must then be accompanied by entry into a supervision agreement. For all other hearing protectors placed on the market, it is sufficient for the supervision agreement to be in place by 21 April 2019, or earlier at the point in time when an EU type examination certificate is issued.

The IFA offers development examinations as an additional service by means of which manufacturers are able to identify deficits at the prototype stage.