PADILLA REVIEW
CENTER MANILA
Definition of Terms
COSH and Transportation Engineering
OSH standards – set of rules issued by DOLE which
mandates the adoption and use of appropriate practices,
means, methods operations or processes, and working
conditions reasonably necessary to ensure safe and
healthful employment.
Definition of Terms (COSH):
Presidential Decree no. 442 - Otherwise known as the Labor
Code of the Philippines.
This policy issuance institutes consolidated labor and social
laws to afford protection to labor, promote employment
and human resources development and insure industrial
peace based on social justice.
Safety and health committee – A body created within the
workplace tasked with the authority to plan, develop and
implement OSH policies and programs, monitor, and
evaluate the OSH program, and inspect and investigate all
aspects of the work pertaining to the safety and health of
workers.
Republic Act no. 11058 – An act strengthening compliance
with occupational safety and health (OSH) standards and
providing penalties for violations thereof.
Safety and health audit – A regular and critical examination
of project sites, safety programs, records, and management
performance on program standards on safety and health
conducted by the safety officer.
DOLE Department Order no. 198, s. 2018 – This policy
issuance defines and enumerates the implementing rules
and regulations of the act strengthening compliance with
OSH standards.
Safety and health program – A set of detailed rules to
govern company policies, processes, and practices in all
economic activities to conform with OSH standards,
including the personnel responsible, and penalties for any
violation thereof.
DOLE Secretary – This entity shall set and enforce
mandatory occupational safety and health standards to
eliminate or reduce occupational safety and health hazards
in all workplaces. This entity may collect reasonable fees for
the inspection of steam boilers, pressure vessels and pipings
and electrical installations, the test and approval for safe
use of materials, equipment and other safety devices and
the approval of plans for such materials, equipment, and
devices.
Covered workplace – Establishments, projects sites, and all
other places where work is being undertaken wherein the
number of employees, nature of operations, and the risks or
hazards involved in the business required compliance with
the provisions of RA 11058.
Department of Labor and Employment (DOLE) – This entity
is responsible for the conduct of continuing studies and
research to develop innovative methods, techniques, and
approaches for dealing with occupational safety and health
problems. This entity shall be solely responsible for the
administration and enforcement of OSH laws, regulations
and standards in all establishments and workplaces.
Medium-risk establishment – A workplace where there is
moderate exposure to safety and health hazards and with
probability of an accident, injury or illness, if no preventive
or control measures are in place.
Low-risk establishment – A workplace where there is low
level of danger or exposure to safety and health hazards
and not likely or with low probability to result in accident,
harm or injury, or illness.
First-Aider – Any person trained and duly certified to
administer first aid by the Philippine Red Cross or any
organization authorized by DOLE Secretary.
High-risk establishment – A workplace, like construction
sites, wherein the presence of hazard or potential hazard
within the company may affect the safety and/or health of
workers not only within but also persons outside the
premises of the workplace. There is a high level of exposure
to safety and health hazards, and probability of a major
accident resulting to disability or death, or major illness is
likely to occur if no preventive or control measures are in
place.
OSH personnel – A qualified first-aider, nurse, dentist, or
physician engaged by the employer to provide occupational
health services in the establishment, project, site, or
workplace.
OSH consultant – A qualified Safety Officer 4 or its
equivalent, duly certified by DOLE to perform and/or render
consultative services on Occupational Safety and health in
at least two (2) fields of specialization ask determined by
DOLE.
Personal protective equipment – Specialized clothing or
equipment designed to protect workers against safety and
health hazards that may cause serious workplace injuries
and illness, i.e., protection for the body, eyes, head, face,
hands, feet, ears, etc.
OSH practitioner – A qualified Safety Officer 3 or its
equivalent, duly certified by DOLE to render Occupational
Safety and health services in a defined and specific scope or
core competency.
I.
II.
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8-hour OSH orientation
2-hour OSH trainer’s training
PADILLA REVIEW
CENTER MANILA
Definition of Terms
COSH and Transportation Engineering
III. 40-hour basic OSH training course
IV. 48-hour advanced OSH training course
V. 80-hour advanced OSH training course
VI. 320-hour OSH-related training or experience
VII. At least 2-year experience as Safety Officer
VIII. At least 4-year experience as Safety Officer 3
White – It is the color should be used to direct traffic in the
workplace.
RED – It is the color should be used for safety signs relating
to fire protection and combustion warning.
I and II only – the above are the minimum requirements to
be accredited as Safety Officer
ORANGE – It is the color should be used for alert to
designate dangerous parts of machines or energized
equipment which may cause injury/hazard.
III, IV, and VII only – the above are the minimum
requirements for a Safety Officer 3.
Seiri, Seiton, Seiso, Seiketsu, Shitsuke – the 5S’s mean in 5S
of good housekeeping.
III, V, VI, and VIII only – the above are the minimum
requirements for a Safety Officer 4.
Seiri (Sort) – eliminate unnecessary items .
Seiton (Systematize) – arrange and organize.
1-SO2 and 1-SO3 – Minimum number and designation of
safety officer required
Seiso (Sweep) – cleaning the workplace.
1 Full-time – Minimum number of occupational health
nurse required.
Seiketsu (Sanitize)
housekeeping.
2 – Minimum number of first-aider required.
Shitsuke (Self-discipline) – doing things spontaneously
without being told.
–
maintain
high
standard
of
1 Part-time – Minimum number of OH physician required.
Unsafe act – Primary cause of accident that is characterized
by the human action that departs from a standard or
written job procedure or common practice, safety rules,
regulations, or instructions.
3 first treatment room and 2 clinics – Minimum number
and type of occupational health facility required.
4 hrs/day, 3 days/wk – Hours per day and days per week
does a parttime
Unsafe condition – The physical or chemical property of a
material, machine or the environment which could result in
injury to a person, damage or destruction to property or
other forms of losses.
OSH personnel should report to the construction site –
According to OSH standards, there are specific color of
signages for every purpose and that the size of signages
should be calculated based on the distance where it should
be visible or observable.
Safety hazard – A risk associated with poorly guarded or
dangerous equipment and machinery that may cause injury.
RED (Fire Protection) – to call attention to fire protection
equipment apparatus and facilities.
Health hazard – A risk associated with exposure to
dangerous substance or conditions that may cause illness/
disease.
GREEN (Safety) – designating “safety”
Elimination – In demolition safety, this control is
characterized by ensuring separation between the public
and the demolition activities.
White (Traffic) – white, black, or a combination of these for
designation of traffic and housekeeping marking. – to
designate caution and for marking physical hazards.
Substitution – control is demonstrated by the use of power
shears, in place of grinding or oxy-acetylene cutting, where
there is a risk of fire.
ORANGE (Alert) – to designate dangerous parts of
machines or energized equipment which may cause
injury/hazard
Engineering control – Installation of scaffolds, platforms,
guardrails, shoring and bracing to support loads are
examples of this type of risk control.
BLUE (Precaution) – to designate caution limited to warning
against starting, use of, or movement of equipment under
repair or being worked upon.
Administrative control – This type of risk control includes
limiting the amount of time a person is exposed to a
particular hazard, implementing safe working procedures
for all hazardous tasks, and training all personnel.
PURPLE (Radiation) – to designate radiation hazards
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PADILLA REVIEW
CENTER MANILA
Definition of Terms
COSH and Transportation Engineering
6th, 12th, and 18th meter – For a fixed ladder used to
ascend height of more than 20 meters, it is the height
should landing be provided.
Sheathing – This is the vertical member of shoring and
timbering which directly resists pressure from side of an
excavation.
Fall protection system – An engineering control or set of
PPEs prevents you from falling like guardrails, covers,
restraints, etc.
Fall arrest system – An engineering control or PPE set that
protect you after you fall which is characterized by stopping
the fall before you hit the surface like net/mesh and/or
body harness.
Wale – It is the longitudinal member of shoring and
timbering which directly resists pressure from sheathing.
HIRAC – A formal process to identify potential hazards
related to an activity or operation, analyze the level of risk
associated with those hazards, and propose controls to
reduce the level of risks.
Strut – It is the transverse member of shoring and timbering
which directly resists pressure from sheathing or wales.
Scaffolds – A general term used to describe a temporary
structure of timber or metal work with a platform used in
the construction, alteration, or demolition of a building, or
other maintenance work used to support workers or to
allow the hoisting and lowering of workers, their tools, and
materials.
Job hazard analysis – A formal process to identify the
dangers of specific job tasks in order to reduce the risk of
injury to workers. It involves breaking down the steps of
performing a job, identifying hazards at each step, and
creating controls to keep workers safe while performing
that task.
Suspended scaffold – A scaffold hanging by means of ropes
or chains capable of being lowered or raised by winch,
pulley, block, or such other means.
4 – All stairs, platform, and landings shall be of sufficient
strength to sustain safely a live load of not less than 490
kg/m2 with factor of safety of ___.
Single scaffold – A platform supported by a single row of
uprights or standards tied along the wall, connected
horizontally by a ledger, and supporting putlogs which rests
on ledger on one side and in holes left in walls on the other.
1.10 m – According to OSH standards, this shall be the
minimum width of stairs (including handrails).
0.90 m – This is the minimum width of stairs without the
handrails.
Double scaffold – A platform supported on two rows of
uprights or standards parallel to the wall of a building
connected by horizontal ledgers and is independent from
the building wall.
1.5:1 (33°) – the following stairway slope (H:V) fits the
criteria defined in the OSH standards for stair pitch?
Standard/Upright – It is the vertical member of scaffold
transmitting the load to the ground or to a base plate.
3:1 (18°) – the following pitch qualifies for ramp installation.
Fixed ladder – In a pitch of more than 45° , what should be
provided instead of stairs.
Ledger/Stringer – A scaffold bracing, which extends
horizontally from standard to standard forming right angles
with the putlogs and forms a tie between the standards.
3.6 m – is the maximum clear height between stairway
landings.
Putlogs/Bearer – A scaffold member spanning between a
ledger and a building wall or between two ledgers upon
which the platform rests.
2.0 m – According to OSH standard, headroom shall be
provided at all points in the stairwell, what is the minimum
vertical clearance from the top of the tread in line with the
face of the riser.
Brace – A scaffold member that holds standards or uprights
in a fixed position to prevent any lateral movement.
25 cm – This is the minimum dimension of treads (exclusive
of nosing and projections).
1.00m – In excavation safety, adequate shoring and
timbering to prevent collapse shall be provided for
excavation of depth more than __ meters.
20 cm – The riser should have a maximum height of how
many meters.
Over 6.6 meters deep – excavation depth should the
services of a Structural engineer for the design of the
excavation be required
90° – What is the maximum pitch (slope) for a fixed ladder.
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PADILLA REVIEW
CENTER MANILA
Definition of Terms
COSH and Transportation Engineering
Ingress and egress – Open excavation of over 1 m. deep
shall be provided with what, in case of flooding or collapse
of the excavation work.
4 – ladders shall be provided for a 60-meter length
excavation as means of access and/or exit.
Definition of Terms (Transportation Engineering)
0.83 m – The ladder provided as ingress/egress in an
excavation shall extend at least how many meters above
the top of the excavation to provide a firm handhold when
stepping on or off the ladder?
Traffic Signs – device mounted on a fixed support
(permanent signs) or portable support (temporary signs)
whereby a specific message is conveyed by means of words
or symbols placed or erected for the purpose of regulating,
warning or guiding traffic.
20 m – Timber/bamboo scaffoldings shall be limited to a
height of how many meters from the ground or base?
Regulatory Signs – signs that inform road users of traffic
laws and regulations which, if disregarded, will constitute an
offense.
Structural metal – What scaffolding materials shall be used
at heights over 20 meters.
Special Instruction Signs – signs that instruct road users to
meet certain traffic rule requirements or road condition.
0.60 – In the construction of timber scaffolds, the size of the
standard shall not be less than 8.9 cm. (3 in.) in diameter or
its equivalent and when it is necessary to extend a standard,
the overlaps shall not be less than how many meters?
Warning Signs – warn road users of condition on or
adjacent to the road that may be unexpected or hazardous.
30 cm – In scaffolds platform for painters, decorators, and
similar types of workers, when the platform is not more
than 2 m. (6 ft.) above the ground floor, what is the
minimum width of the plat form?
• Guide Signs (Informative Signs) – inform and advice road
users of directions, distance, routes, the location of
services, and points of interests • Roadwork Signs - warn
or advise of temporary hazardous conditions that could
endanger road users or the men and equipment engaged
on roadwork.
1.0 m – For platforms used by men, tools, and materials
that is more than two 2 m. (6 ft.) above the ground or floor,
the minimum platform width is?
• Overhead Signs – signs which provide means of
displaying essential traffic information on wide multi-lane
roads, where some degree of lane use control is required,
or where side-of-road clearance is insufficient to
accommodate a roadside sign.
2.0 m – Fall protection equipment shall be required when
working, the minimum height
Over 10 m – the height shall workers be required to use fall
arrest equipment.
• Barriers – highway appurtenances designed to prevent
vehicular penetration from the travel way to areas
behind the barrier such as to minimize damage to
impacting vehicles and their occupants, and to reduce the
risk of injuries to pedestrians and workers.
• Flashing Lamps – warning devices used to supplement
other controls and devices necessary to alert motorists of
construction and maintenance activities or obstructions
in the roadway.
• Delineators – light retro-reflecting devices mounted at
the side of the roadway, in series, to indicate the
roadway alignment.
• Traffic Cones – devices which may be conical in shape or
tubular- shaped capable of performing channelization of
traffic which may be set on the surface of the roadway or
rigidly attached for continued use.
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PADILLA REVIEW
CENTER MANILA
Definition of Terms
COSH and Transportation Engineering
• Temporary Curbing – roadwork devices consisting of precast concrete sections, sandbag, and others which, may
be used to guide traffic at the construction site.
• Convey a clear, simple message
• Command respect; and
• Give adequate time for proper response It should be
noted that when all sign rules have been followed, some
visual judgment must be exercised in adjusting sign
elements.
• Flexible Post or Bollard – device used in place of rigid
barrier posts or traffic cones with a minimum of 450 mm
by 50 mm wide with alternate bands of contrasting color
as seen by approaching traffic for delineation of traffic.
The following general rules are to be applied when
designing the sign face:
• Cramping of legend is to be avoided;
• Avoid large areas of blank panel, particularly blank areas
not symmetrically disposed across the panel;
• If there are two list of legends side by side (e.g., as on
Reassurance Signs) it is necessary to left justify the left
list and right justify the right list;
• Elements such as arrows and symbols may sometimes
have to be larger than the principal legend would
normally require. For example, an arrow relates to
several lines of legends on a direction sign
The standard colors for signs are as follows:
• Red is used as a background for STOP signs, as border
color on GIVE WAY signs, warning signs and prohibitive
signs in the regulatory type.
• Black is used as legend color for signs having white,
yellow, orange, fluorescent orange, fluorescent yellow
green background and as chevron for hazard makers.
• Yellow is used as background color for road signs.
• White is the background color for most signs and legends
for some colored background.
• Fluorescent Yellow Green is used as background color for
signs related to pedestrian movement, school zones, and
road work hazard markers to give additional emphasis
and guidance to vehicle operators.
• Fluorescent Orange is used as background color for
roadwork signs whose legends relate to personal
working.
• Green is used as background color for direction signs.
• Blue is used as background color for service signs.
• Brown is reserved as background color for all tourist
facility directional and information signs.
Four Sizes for Regulatory Signs:
• Size A for urban low speed roads;
• Size B for rural roads with speed limits between 60 and
70 kph;
• Size C for high-speed rural highways’ multi-lane urban
roads
• Size D for Expressways
Classification of Warning Signs:
• Horizontal Alignment Signs
• Intersection and Junction Signs
• Advance Warning of Traffic Control Device Signs
• Road Width Signs
• Road Obstacle Signs
• Pedestrian and School Signs
• Railway Level Crossing
• Supplementary Signs
• Other Warning Signs
Classifications of Signs
Signs are classified in the following groups according to
their use:
• Regulatory Signs
• Warning Signs
• Guide Signs or Informative Sign
• Signs for Expressways
• Signs for Special Purposes
Signs in Directional Signing series are usually classified into
four categories:
• Those installed in advance of the intersection.
• Those installed at the intersection.
• Those on departure from the intersection.
• Those installed on expressways.
Classification of Regulatory Signs:
• Priority Signs
• Direction Signs
• Prohibitive or Restrictive Signs
• Speed Signs
• Parking Signs
• Miscellaneous Signs
Classification of Guide Signs:
• Advance Direction Sign
• Intersection Direction Sign
• Reassurance Direction Sign
• Finger Board Direction Sign
• Street Name Signs
• Town Name and Geographical Feature Signs
• Service Signs
• Tourist Information and Tourist Destination Signs
• Route Markers
Hazard Markers Uniformity of application is as important
as standardization with respect to design and placement.
Identical conditions should always be treated with the same
type of signs so that road users can readily anticipate the
course of action required.
To be effective, the road sign should meet the five basic
requirements:
• Fulfill a need
• Command attention
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PADILLA REVIEW
CENTER MANILA
Definition of Terms
COSH and Transportation Engineering
One-Way hazard markers – indicate to the approaching
driver the direction to be followed if the marker appears in
the driving path. They may point to the left or right as
appropriate and are used as follows:
• To delineate an abrupt narrowing of pavement, for
example, at a lane drop;
• At exposed ends of raised median islands where traffic is
required to pass to one side;
• On central island of a roundabout facing entering traffic;
and
• To delineate the curve approach just prior to entering an
intersection.
• Function of the road
• Anticipated operating speed
• Anticipated speed limit Warrants for Marking Center
Lines
A center line may be marked on an urban or rural road if
one or more of the following conditions are met:
• Two lane road (greater than 6 m in width) carrying an
Annual Average Daily Traffic (ADT) in excess of 1000
vehicles:
• Two lane road (less than 6 m but more than 5 m in width)
carrying an ADT in excess of 300 vehicles; and
• Winding roads with widths of 5 m or more.
Pavement markings have definite limitations:
• They are subject to traffic wear and require proper
maintenance;
• They may not be clearly visible if the road is wet or dusty;
• They may be obscured by traffic;
• Their effect on skid resistance requires careful choice of
materials; and
• They cannot be applied on unsealed roads.
Barrier lines may consist of either:
• Two unbroken yellow lines;
• Single unbroken yellow line; or,
• Single yellow line with a broken white line.
The following are the cases where barrier lines should be
used:
• As center lines on approaches to signalized intersections;
• As center lines of multi-lane roads where overtaking must
be prohibited, because of sign restrictions;
• ‘No-Passing’ zones where there is a restricted sight
distance due to horizontal or vertical curves, or both; and
• As center lines on approaches to railway crossings
The elements to consider when planning Expressways are:
No frontage access;
• Development set well back from the highway;
• Grade separated intersections for extremely high flows
and other intersecting expressways;
• Number of intersections to be minimized and
• Where necessary or for emergency purposes,
parking/stopping to be provided clear of the main
carriageway.
Warrants for Use Because of the high cost of installation
and maintenance, use of raised pavement markers may be
considered only in the following condition:
• In hilly areas where fog and rain are frequently the causes
of traffic accidents;
• In winding roads and accident-prone areas.
The elements to consider when planning National Roads
are:
• Limited frontage access
• Development set well back from the highway
• All access to premises provided via provincial roads
• Number of intersections to be minimized
• Suitable at-grade channelized intersections for minor
flows and other elements
• No roadside vendors Color of Pavement Markings
The provision of safety sight distance depends on the
characteristics of the driver such as:
• Alertness of driver
• Recognition of the hazard
• Actions available to the driver – to stop or to change
direction
The color of pavement markings shall be white except for
the alternative uses of yellow as specified below:
• Double yellow no-passing lines;
• Unbroken portion of no-passing lines;
• Curb markings for prohibition of parking;
• On islands in line of traffic;
• Bus and PUJ lanes; and,
• Keep Intersection Open Markings Red shall be used in:
• No Loading/Unloading Zone
• Fire lane zone
The provision of safety sight distance depends on the
characteristics of the vehicle such as:
• Type of vehicle – car or truck
• Friction between the tire and the road
• Eye height of the driver
• Speed of vehicles
The provision of safety sight distance depends on the
characteristics of the road environment such as:
• Road geometry – grade and curvature sight limitations
• Road surface – sealed or unsealed, smooth or rough •
Road illumination at night
Design Speed – The choice of an appropriate design speed
for a road project is important to ensure a safe design.
Each type of sight distance consists of three elements:
• Driver Eye Height
• Object Height
When choosing a design speed, the following factors need
to be considered:
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PADILLA REVIEW
CENTER MANILA
Definition of Terms
COSH and Transportation Engineering
• Sight Distance
movements (and provide for them at other intersections
along the route)
• Control movements to reduce the possibility of conflict
and
• Clearly define vehicle paths by use of pavement markings
There are two components in stopping sight distance:
• Reaction distance – the distance traveled while the driver
perceives a hazard, decides to take action, then acts by
starting to apply the brakes to start slowing down
• Braking distance – the distance required for the vehicle to
slow down and stop
PORTS, HARBORS AND COASTAL ENGINEERING:
Harbor – A protected water area to provide safe and
suitable accommodation for ships for the transfer of cargo,
refueling, repairs, etc. Harbors may be subdivided into:
a. Natural harbors: harbors protected from storms and
waves by the natural configuration of the land.
Four different criteria used for the establishment of sag
vertical curves:
• Headlight sight distance
• Passenger comfort
• Drainage control
General appearance PPA has used MLLW as the datum line
for design of port facilities in accordance with charts. But
there are many ports of which low tide go down very often
below MLLW. For instance: (Port Cebu) According to the
tide table (1991) of NAMRIA, the frequency of tide below
MLLW is 213 times/year and the maximum amount of the
value is -0.51 m.
b. Semi-natural harbors: harbors with both natural and
artificial protection. c. Artificial harbors: harbors
protected from the effect of waves by means of
breakwaters, or harbors created by dredging.
Port – A sheltered place where the ship may receive or
discharge cargo. It includes the harbor with its approach
channels and anchorage places. Ports may be subdivided
into:
a. Ocean ports: ports located on coasts, tidal estuaries
or river mouths where the port can be reached
directly by ocean-going ships.
b. Inland waterway ports: ports located on navigable
rivers, channels and lakes.
Under this condition it is dangerous for ships to utilize the
port. Shoulder paving is a valuable method of providing:
• Integrity of the pavement
• Width to place edge line pavement markings
• Additional safety to prevent vehicles skidding or drivers
losing control in gravel.
• Low maintenance costs compared with unpaved
shoulders
Fairway – a navigable channel in a harbor, offshore etc; the
usual course taken by vessels in such places.
Element of Berthing Facility:
• Planned Water Depth
• Design Water Depth
• Coping/Crown Elevation
• Length - Standard Part, Approach Part
• Width of Apron
• Slope of Apron
Berth – A place where the ship can moor. In the case ofa
quay or jetty structure, it will include the section of the
structure where labor, equipment and cargo move to and
from the ship.
Berth structure – An artificial landing place for the loading
and unloading of ships. Berth structures can be subdivided
into:
There are four types of escape ramps:
• Sand Pile
• Descending Grade
• Horizontal Grade
• Ascending Grade
A. Wharf – A continuous structure built parallel to along the
margin of the sea or alongside riverbanks, canals, or
waterways where vessels may lie alongside to receive or
discharge cargo, embark or disembark passengers or lie at
rest.
Types of intersections that generally exist on the road
network are: • Unflared and unchannelized intersections
(without widening or traffic islands):
• Flared and unchannelized intersections (with widening
but without traffic islands) and
• Channelized intersections (traffic islands to guide traffic)
Quay – this term can be substituted to wharf when applied
to great solid structures in large ports. In stability
calculation of gravity type quay wall, the following
matters should be examined:
a. Sliding of the wall
b. Bearing capacity of foundation
c. Overturning of the wall
d. Circular slip and settlement
Principles of good design to reduce the likelihood of traffic
accidents include:
• Minimize the speed of vehicles at potential collision
points
• Separate movements and points of conflict by
channelization, or in some situations, prohibit certain
B. Pier – Any structure built into the sea but not parallel to
the coastline and includes any stage, stair landing place,
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PADILLA REVIEW
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Definition of Terms
COSH and Transportation Engineering
landing stage jetty, floating barge, and pontoon, any bridge
or other works connected there with.
disturbances in navigation channels, and multiple reflected
waves from quay walls can cause agitations within harbors.
C. Jetty – a landing stage or small pier at which boats can
dock or be moored.
Wave Shoaling – is one of the important factors that lead to
changing of the wave height in coastal waters. It exemplifies
the fact that the wave height in shallow waters is also
governed by the water depth and wave period.
D. Dolphin: a berth structure for mooring the ship on the
open sea - An isolated piled or gravity structure used either
to maneuver a ship or to facilitate holding it in position at its
berth.
Wave Breaking – At places where the water depth is no
more than about three times the equivalent deep water
wave height decreases rapidly of the wave height due to
wave breaking shall be considered.
E. Dock – a type of dock consisting of a rectangular basin
dug into the shore of a body of water and provided with a
removable enclosure wall or gate on the side toward the
water, used for major repairs and overhaul of vessels.
Tides and Abnormal Water Level Astronomical tide – is the
periodic rise and fall of sea level in response to the
gravitational attraction of the sun and moon as modified by
the earth’s rotation.
WAVES:
Significant Wave (significant wave height H1/3 and
significant wave period T1/3)
The essential parameters to characterize the tide are:
The waves in a wave group are rearranged in the order of
their heights and the highest one- third are selected:
a. Mean Sea Level (MSL) – is the average of the sea water
surface for all stages of the tide over a 19- year period.
• Significant Wave – is then the hypothetical wave whose
height and period are the mean height and period of the
selected waves.
• Highest Wave – (highest wave height Hmax and highest
period Tmax) – is the highest wave in a wave group.
• Highest One-Tenth Wave (H1/10, T1/10) – is the wave
whose height and period are equal to the mean height
and period of the highest one-tenth of the waves in a
wave group.
• Mean wave (mean wave height H, mean period T) – is
the wave whose height and period are equal to the mean
height and period of all of the waves in a wave group.
• Deepwater Waves (Deepwater wave height H0 and deepwater wave period T0) – is the wave at a place where the
water depth is at least one- half of the wavelength; the
wave parameters are expressed with those of the
significant wave at this place.
• Equivalent Deepwater Wave Height (H0’) – is a
hypothetical wave height that has been corrected for the
effects of planar topographic changes such as refraction
and diffraction.
b. Mean Low Water (MWL) – is the height of the low water
over a 19-year period.
Wave Refraction – occurs in intermediate depth to shallow
waters. The change in wave height and wave direction due
to the change in local wave velocity caused in water depth.
Seiche – is a phenomenon involving abnormal oscillations of
the water level with a period of approximately a few
minutes to a few tens of minutes. It occurs when small
fluctuations of the water level are generated by micro-scale
variations of the atmospheric pressure by an air front or a
low pressure in the outer sea, and the components of those
oscillations whose period is the same as a natural period of
the harbor are amplified through resonance.
c. Mean Lower Low Water (MLLW) – is the average height
of the lower low waters over a 19-year period.
d. Mean High Water (MHW) – is the average height of the
high waters over a 19-year period.
e. Mean Higher High Water (MHHW) – is the average
height of the higher high water over a 19-year period.
Storm Surge – is abnormal rise of the sea level that occurs
when a typhoon passes by. This rise above normal level on
this open coast is due to atmosphere pressure reduction as
well as that due to wind stress.
Tsunamis -– are wave with an extremely long period that
mainly occur when there is a sudden large- scale sea floor
movement usually associated severe, shallow focus
earthquake.
Wave Diffraction – is a phenomenon whereby waves wheel
into region that is screened by something like a breakwater.
Wave Reflection – the waves reflected from port and
harbor facilities can exercise a large influence on the
navigation of vessels and cargo handling. For example,
waves reflected from vertical breakwaters can cause
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