Ⅰ. Introduction.
In general this risk assessment report for the PASSENGER BOARDING BRIDGE, model MTB-Ⅱseries and its variants made by V ATAPLE MACHINERY (KUNSHAN) CO., LTD. was carried out in accordance with the requirements of Machinery Directive and the standards of EN ISO 14121-1 and DINV 19250, in which an explicit risk level is evaluated with 4 factors described in next clause.
After the first assessment, some measures to eliminate the risks are given for the modification of machine or of relative documents with taking into account the explicit C-type EN standard or related B-type standard.
While taking appropriate provisions for the existing risks, the procedures and principles to eliminate the risk according to the most general B-type standard for any kind of machine, EN 292-partⅠ, are followed, i.e.:
pulleys-First step: consider the possibility of eliminating risk at design stage.
-Second step: if impossible, protect the dangerous zone with appropriate design of safety guard or safety device.
-
Third step: If above impossible, give warning signs to draw attention of operators about the residual risks.
In addition, some check list drawn from the explicit C-type EN standards, which are found suitable for or near the characteristic of this machine, are used to help developing the provisions for the elimination of the risks.
Finally the risk assessment was carried out again to ensure this machine and its relative documents are totally compliance with the Machinery Directive.
Ⅱ. Risk assessment Methodology
This risk assessment report is based on the methods mentioned in the EN ISO 14121-1 and DINV 19250 standards, and the 4 factors S-A-G-W have been used for evaluating the level of risks.
(a)S: Severity of possible harm
- S1: Slight (normally reversible)
- S2: Serious (normally irreversible)
- S3: Cause a few men die
- S4: Calamity or cause many men die
(b)A: Frequency and duration of exposure
- A1: Seldom to very often
- A2: Frequent to continuous
(c)G: Possibilities of avoidance
- G1: Possible
- G2: Impossible
(d)W: Probability of occurrence of harm
- W1: Low
- W2: Medium
-
W3: High
Solutions for the level of hazards
1: Protected by warning sign
2: Protected by guard and warning sign
3: Consider the other design, choose the best one, and add both guard and warning sign
4: Consider another two designs, choose the best one, and add both guard and warning sign  5: Consider another three designs, choose the best one, and add both guard and warning sign
No. Hazards
Level
W
G
source S    A
Mechanical hazards
S2A1 G1 W1 -
1.0-1 Mechanical hazards due to machine parts or work
pieces
1.0-2 Mechanical hazards due to accumulation of energy
N/A inside the machinery
1.1 Crushing/Squeezing S2A1 G1 W1 -
1.2 Shearing S2A1 G1 W1 -
severing N/A
or
1.3 Cutting
1.4 Entanglement N/A
trapping S2A1 G1 W1 -
or
1.5 Drawing-in
1.6 Impact S2A1 G1 W1 -
puncture S2A1 G1 W1 -
or
1.7 Stabbing
1.8 Friction or abrasion S2A1 G1 W1 -
1.9 High pressure fluid injection or ejection S2A1 G1 W1 -
Electrical hazards
2.1 Contact with live parts S2A1 G1 W1 -
S2A1 G1 W1 -
2.2 Contact with parts which have become live under
faulty conditions
2.3 Approach to live part under high voltage N/A
phenomena N/A
2.4 Electrostatic
N/A
2.5 Thermal radiation or other phenomena such as
projection of molten particles and chemical effects
from short-circuits, overloads etc.
Thermal hazards
N/A
3.1 Burns, scalds and other injuries by a possible contact
of persons with objects or materials with an extreme
high or low temperature, by flames or explosions and
also by the radiation of heat sources
3.2 Damage to health by hot or cold working environment N/A
Hazards generated by noise
4.1 Hearing loss (deafness), other physiological disorders N/A
N/A
speech communication, acoustic
with
4.2 Interference
signals, etc.
Hazards generated by vibration
5.1 Use of hand-held machines resulting in a variety of
N/A neurological and vascular disorder
S2A1 G1 W1 -
5.2 Whole body vibration, particular when combined with
poor postures
Hazards  generated  by  radiation
6.1 Low frequency, radio frequency radiation, microwaves N/A 6.2 Infrared, visible and ultraviolet light N/A 6.3 X and gamma rays N/A 6.4 Alpha, beta rays, electron or ion beams, neutrons N/A 6.5 Lasers S2A1 G1 W1 -
Hazards generated by materials and substances processed or used by the machinery
7.1 Hazards from contact with or inhalation of harmful
N/A fluids, gases, mists, fumes and dusts
7.2 Fire and explosion hazard S2A1 G1 W1 -
N/A
micro-biological (viral or bacterial)
7.3 Biological
and
hazards
Hazards generated by neglecting ergonomic principles in machine design
8.1 Unhealthy postures or excessive effort N/A
N/A 8.2 Inadequate consideration of hand-arm or foot-leg
anatomy
8.3 Neglected use of personal protection equipment N/A 8.4 Inadequate local lighting N/A 8.5 Mental overload or underload, stress N/A 8.6 Human error, human behavior S1A1 G1 W1 -
or identification of manual
S2A1 G1 W1 - design,
location
8.7 Inadequate
controls
8.8 Inadequate design or location of visual display units S1A1 G1 W1 -
Combination of hazards
9 Combination of hazards N/A
Unexpected start-up, unexpected overrun/over-speed
10.1 Failure/disorder of the control system S2A1 G1 W1 - 10.2 Restoration of energy supply after an interruption N/A 10.3 External influences on electrical equipment S2A1 G1 W1 -10.4 Other external influences (gravity, wind, etc.) N/A 10.5 Errors in the software N/A
S1A1 G1 W1 - 10.6 Errors made by the operator (due to mismatch of
machinery with human characteristics and abilities, see
8.6)
Impossibility of stopping the machine in the best possible conditions
N/A 11 Impossibility of stopping the machine in the best
possible conditions
Variations in the rotational speed of tools
12 Variations in the rotational speed of tools N/A
Failure of the power supply
13 Failure of the power supply S2A1 G1 W1 -
Failure of the control circuit
14 Failure of the control circuit S2A1 G1 W1 -
Errors of fitting
15 Errors of fitting S1A1 G1 W1 -
Break-up during operation
16 Break-up during operation S2A1 G1 W1 -
Falling or ejected objects or fluids
17 Falling or ejected objects or fluids S2A1 G1 W1 -
Loss of stability / overturning of machinery
18 Loss of stability / overturning of machinery N/A
Slip, trip and fall of persons (related to machinery)
19 Slip, trip and fall of persons (related to machinery) S2A1 G1 W1 -
Additional hazards, hazardous situations and hazardous events due to mobility
20 Relating to the traveling function
20.1 Movement when starting the engine N/A 20.2 Movement without a driver at the driving position N/A 20.3 Movement without all parts in a safe position N/A 20.4 Excessive speed of pedestrian controlled machinery N/A 20.5 Excessive oscillations when moving N/A
N/A 20.6 Insufficient ability of machinery to be slowed down,
stopped and immobilized
Linked to the work position (including driving station) on the machine
21.1 Fall of persons during access to (or at/from) the work
S2A1 G1 W1 - position
21.2 Exhaust gases/lack of oxygen at the work position N/A
S2A1 G1 W1 - 21.3 Fire (flammability of the cab, lack of extinguishing
means)
N/A
21.4 Mechanical hazards at the work position:
a)contact with the wheels;
b)rollover;
c)fall of objects, penetration by objects;
d)break-up of parts rotating at high speed;
e)contact of persons with machine parts or tools
(pedestrian controlled machines).
21.5 Insufficient visibility from the work positions N/A
lighting S2A1 G1 W1 - 21.6 Inadequate
seating N/A 21.7 Inadequate
21.8 Noise at the work position N/A 21.9 Vibration at the work position N/A 21.10 Insufficient means for evacuation/emergency exit N/A