参考General Specification for Tunneling Methods of Measurement and Price Inclusions中相关规定
54.06 – Lighting and ventilation
54.06.01
Lighting
The Contractor shall design, supply, install and maintain a lighting
system for purposes of execution of the work. Minimal light
intensity in each underground system measured at the floor of the
tunnel shall be as follows as specified in Israel Standard 5567 and
below:
a. General underground lighting – 10 Lux.
b. Local lighting at the excavation face or at which work is being
performed – 100 Lux;
c. Lighting of safety installations in dangerous locations as
determined by the Supervisor – 30 Lux;
d. Overhead area lighting at the entrance areas – 15 Lux.
In addition, the Contractor shall equip anyone present in the tunnel
with personal miner's lanterns and shall also equip portable
machinery and equipment in the tunnels with high intensity
headlights.
54.06.02
Ventilation
54.06.02.00
General
The Contractor must supply the required ventilation system for
execution of the work, including electrical connections, various fan
installations, ducts, etc. The regular and continuous supply of fresh
air to all parts of the tunnel shall be ensured in a quantity and quality
as defined in Israel Standard 5567 and below.
Partitioning between work areas shall, if required, be as specified in
the Special Specification.
The design, supply, installation and maintenance of the ventilation
system shall be imposed on the Contractor
54.06.02.01
Air quantities
The supply of required quantities of fresh air in order to remove
dangerous levels of dust, gases, smoke etc. shall ensure the
maintenance of pollutant concentrations in the air under the
maximum permitted by law or as specified in Subsection 54.06.02.03.
The supply of required quantities of fresh air for work equipment
planned with a fixed flow rate, in a single direction, shall not be less
than 2.8 m³ per minute (or 47.2 L per second) for each brake
horsepower in diesel equipment, and that in addition to 5.6 m³ per
minute (or 94.4 L per second) of fresh air to each person present
underground.
54.06.02.02
Air flow
velocity
Air flow velocity at each point and full cross-section of the tunnel
shall be not less than 0.5 m per second. Measurement of velocity
shall be performed routinely by ensuring minimum requirements for
air flow. In large halls having a cross-section exceeding 100 m², this
velocity will be required to be met at the entrance and exit from the
hall.
54.06.02.03
Gas and dust
levels
Toxic gas levels shall not in any case, time or place exceed the limits
as indicated in Israel Standard 5567 and below:
Carbon dioxide CO2: 5000 ppm (0.5%) of the air in the tunnel;
Carbon monoxide CO: 30 ppm (0.0030%) of the air in the tunnel;
Nitrogen dioxide NO2: 3 ppm (0.0003%) of the air in the tunnel;
Hydrogen sulfide (H2S): 10 ppm (0.001%) of the air in the tunnel;
Methane: 1.5% at the tunnel excavation face, 1% in other parts of the
tunnel;
Other flammable gasses: 40% of the lower explosive limit at the
tunnel excavation face, 20% of the lower explosive limit in other
parts of the tunnel.
Dust levels at all stages of tunneling shall be maintained in the
framework of safe limits as determined by law or in the regulations
and instructions of the Safety Officer of the Ministry of Industry,
Trade & Employment Work Safety Regulations (Occupational Health
and Public Safety for Those Working with Harmful Dust) 5744-1984,
and ensuring that the quantity of dust in the tunnel system will not
exceed an average of 2 mg per cubic meter per 8 work hours. The
work shall be discontinued and shall not be renewed until the
concentration of dust particulates in the air declines to a level of
under 1 mg per cubic meter.
The Contractor shall take all measures necessary to reduce quantities
of dust, including the use of devices for wetting the rock during
drilling or with water spray devices assembled on the tunneling
machine.
In any case where the level of toxic gases exceeds that defined above,
all the works in the tunnel shall be stopped immediately and the
workers shall be sent outside.
In any case where the level of flammable gases exceeds that defined
above, all sources of the heat or ignition shall be shut off and
removed, and all equipment other than ventilation equipment shall be
immobilized until the level of gases will be reduced under the
permissible quantity.
Such work stoppages shall be imposed on the Contractor.
