Safety and safety planning - Tunnel Engineering: Basics and Additional Services for Design and Construction - page 304

into German law by the Federal Republic of Germany. This was implemented in the 9 th
regulation for device safety protection and has thus been valid since the 1 January 1993.
If the safety features of a tunnel boring machine are constructed in accordance with the rel-
evant harmonised EN standard, then it can be presumed that the provisions of the machin-
ery directive are fulfilled. Therefore several EN standards are being produced by working
group 4 of the technical committee TC 151 in CEN.
In detail, these standards are:
EN 815: Safety of unshielded tunnel boring machines and rodless shaft boring machines
for rock.
EN 12336: Tunnelling machines - Shield machines, thrust boring machines, auger boring
machines, lining erection equipment - Safety requirements.
EN 12110: Tunnelling machines - Air locks - Safety requirements.
EN 815 is currently being revised with the aim of “increasing fire protection”.
EN 12336 still has the status of a provisional standard, but has been presented for formal
voting; the German ministry of trade and employment has applied for a revision of EN
12110.
Manufacturers of tunnel boring machines can subject their products to a voluntary safety
test, which is offered by the testing institute accredited by the body responsible for ac-
cident insurance in civil engineering. This can investigate the conformity of the machine
with the machinery directive and issue an independent confirmation.
Design and operation. Clients are also assigned safety-related tasks, which are laid down in
the “health and safety protection on construction sites” regulations (Baustellenverordnung
- BaustellV, see Chapter 8.6). In combination with the law concerning health and safety at
work ArbSchG, this implements the EU directive 92/57 EEC (see also Section 8.2.2).
The health and safety protection requirements for the handling and operation of these
machines are essentially determined by the EU directives 89/391/EEC (see also Section
8.2.1) and 96/63/EC, which are based on Article 137 of the EU treaty and specify mini-
mum regulations for all employees in the EU area. In German law, these directives are
implemented in the law concerning health and safety at work (ArbSchG) from 07/08/1996
and the working equipment regulations (BetrSichV) from 27/09/2002. These laws empha-
sise an extensive evaluation of dangers and documentation by the employer, which must
be in keeping with the state of technology.
If substances that could endanger health could be liberated by the operation of a tunnel
boring machine, the provisions of the hazardous substances regulations (GefStoffV) are
applicable. Measures are to be provided (extraction, filtering, etc.) in order that the limit
concentrations laid down in the Technical rules for hazardous substances 900 (TRGS 900)
are complied with.
If tunnel boring machines are used with a pressurised excavation chamber and this has to
be accessible for checking, maintenance and repair work, then the compressed air regula-
tions are applicable up to an excess chamber pressure of 3.6 bar. Higher pressures are only
permissible with an exceptional permit from the responsible authority.