Capital and operational costs

Topic 28

Capital costs

Capital costs are amounts that are spent to acquire, to replace, to add to or to effect major repairs on a building and to some of its equipment. They are expenditures that create long lasting value, capital costs are usually depreciated over a period of years instead of being included in the operating expenses in one year.

Operational costs

Operational costs are meant for equipment maintenance, replacement and installation(not major repairs)

Workplace safety

Topic 27

What is Workplace safety

It is about preventing injury and illness to employees and volunteers in the workplace

What is WSHA

Is Workplace Safety and Health Act.  An act to protect the safety, health and welfare of persons at work in workplaces.  This act requires every person at the workplace to take reasonably practicable steps to ensure the safety and health of every workplace and worker.

What does reasonably practicable mean?

An action is considered to be practicable when it is capable of being done.

Whether it is also reasonable is taken into the following account:

  1. Severity of injury or harm to health
  2. Degree of risk (or likelihood)
  3. Knowledge of hazard and the ways of eliminating, reducing or controlling it
  4. Availability, suitability and cost of safeguards

Duties of an employed worker

  1. Must adhere to safe work procedure introduced at the workplace
  2. Must not endanger himself or others working around through unsafe behaviour
  3. Must not tamper with any safety device or undertake any wilful or reckless acts
  4. Always correctly use any personal protective equipment provided at work

Enforcement measures

  1.  Workplace inspections
  2.  Investigations into a workplace accident or incident
  3.  Suspension of Certificates
  4.  Remedial Order & Stop Work Order
  5.  Composition fines
  6.  Prosecution

WSH(Incident reporting) Regulations

To ensure that OSH data in Singapore are comprehensive.

iReport ensures a single reporting point under WSHA and WCA.  No double reporting is required.  This is also to be in-line with international practice.

Duty to report all workplace accidents that result in the followings:

  1. Death – Notify not later than 10 days after the accident and submit a report to the Commissioner
  2. Injury – To report when the injured employee is granted more than 3 consecutive days of sick leave or is admitted in a hospital for at least 24 hours for observation or treatment.  Shall report to the Commissioner within 10 days.
  3. Occupational disease – Report to the Commissioner not later than 10 days after receipt of the written diagnosis.  The 31 occupational diseases are specified in the Third schedule of the Workplace Safety and Health Act
  4. Dangerous Occurrence – Notify not later than 10 days, submit a report to the Commissioner

Except any accidents which occurs in the course of :

a person commuting to and fro from any workplace

any person driving any vehicle as part of his work

When workplace has employees more than 150, the number of First-Aiders is one for 150 employees. First Aider is to be retrained every 3 years

When workplace is more than 500 persons, there should be a First-Aid room for emergency treatment

When workplace is more than 25 person, a First Aid box of appropriate category must be provided.

1 Box A for 25 persons or less

1 Box B or 2 box A for 50 persons or less

1 Box C or 2 box B for 100 persons or less

The first aid box must have contents as specified in the “First Schedule”, be properly maintained, checked frequently to ensure that they are fully equipped and items are usable, be clearly identified, be placed in a location that is well-lit and accessible and be under the charge of a person appointed by the occupier.

Always wear Personal Protective Equipment (PPE)

  1. Eye protection for workers. Wear enclosed goggles or face shield over safety glasses if chance of splashing or shattering
  2. Wear ear protection such as ear plugs(moulded or formable) or ear muffs.  For greater than 85 dBA, use ear plugs or ear muffs.  For greater than 100 dBA, use ear muffs and ear plugs
  3. Shoes, lab coat, long pants (gives protection from falling objects and spills/spatters)
  4. Plastic/rubber apron for caustics/corrosive
  5. Correct globes for chemical
  6. Never reach into liquids, use tongs for retrieval

Lockout/Tagout systems

To protect against unexpected startup of a equipment or machine that is supposed to be turned off. (used padlock, cable ties, low-cost clasps, warning sign or I.D tags)  Note that tagout is to be used only in cases where a lock is not feasible.

Permissible noise exposure time

85dBA exposure level for permissible exposure time 8 hours

88dBA exposure level for permissible exposure time 4 hours

91dBA exposure level for permissible exposure time 2 hours

94dBA exposure level for permissible exposure time 1 hour

97dBA exposure level for permissible exposure time 30 minutes

100dBA exposure level for permissible time 15 minutes

Typical noise levels:

SPL                       Example

o db                 Threshold of hearing

40 db               Library

60 db               General Office

80 db               CNC machine

100 db             Pneumatic hammer

120 db              Jet take off

140 db              Threshold of pain

Occupational diseases:

Some of these are:

  1.  Noise Induced Deafness (NID)
  2.  Industrial Dermatitis
  3.  Excessive Absorption of chemicals
  4.  Chemical Poisoning
  5.  Gassing
  6.  Occupational Asthma
  7.  Repetitive Strain Disorder of the Upper Limb

Health Effects

  1. Acute – Short term effects, usually after few minutes, few hours exposure  to high levels of hazard.  eg. Metal fume fever after welding in confined space without wearing respirator
  2. Chronic – Long term effects, usually after months, years of repeated or continuous exposure to low levels of hazard, eg noised induced deafness after 5 years of exposure to loud noise
  3. Local – Occurs at location of contact, exposure, eg contact of caustic with hands causes burns on hands
  4. Systemic -Causes effects at location different from pint of contact and targeted organs such as lungs, liver, kidney, blood, eg inhalation & skin contact with benzene causes leukemia (blood disorder)

Work at height – Refer to the BCA website

For further details, refer to BCA website for courses related to workplace, health and safety

 

 

 

 

 

 

 

 

 

 

 

 

Fire Hazards

Topic 26

What is fire hazard

A fire hazard is a situation that increases the likelihood of a fire or may impede escape in the event a fire occurs.

Examples of fire hazard

  1. Storage or place flammable items such as furniture, papers at the stair case or landing, inside the plant, sub-station or switch rooms, TAS and electrical risers, generator rooms or enclosed fire rated PUB incoming water compartment, etc.
  2. Place flammable items such as furniture, papers outside the plant, sub-station or switch rooms, TAS and electrical risers, generator rooms or enclosed fire rated PUB incoming water compartment,etc.
  3. Obstruction of fire escape routes, eg corridors, escape stair cases, fire hose reels, fire call points, fire main and sub-panels, fire extinguishers, fire hydrant, dry and wet risers, fire access panels, fire breaching inlets, fire-engine hardstanding road or accessways
  4. Stacking items that is very near the sprinkler heads
  5. Install non-fire rated doors for the escape staircases and escape routes
  6. Painting the sprinkler royal flush cap installed on the false ceiling
  7. Blown exit lights or emergency lights
  8. Lack of maintenance of the fire protection equipment
  9. Storage of unlicensed chemicals
  10. Renovation works to tenancy unit affecting fire sprinklers and escape routes are carried out without the local authority approval and application of MAA or fire safety certificates from the relevant authority.
  11. Install locks on fire hose reels and escape doors

Chemistry of fire

The 4 components of the fire tetrahedron are: Flammable (combustible) materials, oxygen or oxidiser, heat and chain reaction.

Fire cannot start without all of these elements being in place.  Fire starts when a flammable material with an adequate supply of oxygen or another oxidiser is subjected to sufficient heat.  It is also able to sustain a chain reaction, which is commonly called the tetrahedron.

 

 

 

BCA Green Mark Building

Topic 8

BCA Green Mark building certification is a green building rating system used to evaluate a building for its environmental impact and performance.  This rating system is endorsed and supported by the National Environment Agency.

This Green Mark rating system provides a comprehensive framework for assessing the overall environmental performance of new and existing buildings to promote sustainable design, construction and operations practices in buildings.

For existing building owners and operators are encouraged to meet their sustainable operations goals and to reduce adverse impacts of their buildings on the environment and occupational health over the entire building lift cycle.

The followings are the assessment criteria that are involved:

  1. Energy efficiency
  2. Water efficiency
  3. Sustainable Operation & Management
  4. Indoor Environmental Quality
  5. Other Green Features and Innovation

The green mark rating is categorised into:

1. Platinum with green mark scoring points of 90 and above to be achieved

2. Goldplus with green mark scoring points of 85 to < 90

3.  Gold with green mark scoring points of 75 to < 85

4. Certified with green mark scoring points of 50 to < 75

Some of the BCA Green Mark Schemes for buildings are:

  1. New buildings – Non Residential 2015
  2. Non-Residential – New buildings (Version 4.1)
  3. Residential new buildings (Version 4.1)
  4. Non-Residential New buildings (Version 4)
  5. Existing Non-residential Buildings (Version 3)
  6. Office Interior (Version 1.1) – For new offices, existing operating offices and existing offices under renovation
  7. Office Interior (Version 1) – For new offices, existing operating offices and existing offices under renovation

For other BCA Green Mark Schemes – refer to the website: www. BCA.gov.sg

BCA Green Mark for Office Interior certification

Refer to BCA website on BCA Green Mark for office interior – point allocations

Prerequisite requirements

To be eligible for Green Mark for Office Interior, the office’s temperature setting should not be lower than 24 degree C unless due to specific needs which will be reviewed on a case by case basis by BCA.

Other prerequisite requirements for Green mark goldplus and platinum rating, refer to BCA website for the Energy Efficiency Index (EEI) and lighting power budget

Elective requirements – refer to BCA website

Existing non residential building green mark certification

Refer to BCA website on BCA Non residential building – point allocations

Prerequisite requirements

I. For buildings using water-cooled chilled water plant

Green Mark Rating – Certified – Building cooling load for chiller less than 500 RT,  the Efficiency (KW/RT) should be at 0.85, more than 500 RT, the WK/RT should be at 0.75

Green Mark Rating – Gold – Building cooling load for chiller less than 500 RT,  the Efficiency (KW/RT) should be at 0.80, more than 500 RT, the WK/RT should be at 0.70

Green Mark Rating – Goldplus – Building cooling load for chiller less than 500 RT,  the Efficiency (KW/RT) should be at 0.75, more than 500 RT, the WK/RT should be at 0.68

Green Mark Rating – Platinum – Building cooling load for chiller less than 500 RT,  the Efficiency (KW/RT) should be at 0.70, more than 500 RT, the WK/RT should be at 0.65

For buildings using air-cooled chilled water plant or unitary air-conditioner

Green Mark Rating – Certified – Building cooling load for chiller less than 500 RT,  the Efficiency (KW/RT) should be at 1.1, more than 500 RT, the WK/RT should be at 1.0

Green Mark Rating – Gold – Building cooling load for chiller less than 500 RT,  the Efficiency (KW/RT) should be at 1.0, more than 500 RT, the WK/RT is not applicable

Green Mark Rating – Goldplus – Building cooling load for chiller less than 500 RT,  the Efficiency (KW/RT) should be at 0.85, more than 500 RT, the WK/RT is not applicable

Green Mark Rating – Platinum – Building cooling load for chiller less than 500 RT,  the Efficiency (KW/RT) should be at 0.78, more than 500 RT, the WK/RT is not applicable

II. Chiller plant M&V instrumentation

Chilled-water side – T in +T out +flow meter = Cooling Load

Condenser water side – T in +T out +flow meter = Heat Rejection

Main control board – Power meters (Chillers, pumps and cooling towers)

Need to provide Permanent Measuring  instruments for monitoring the performance of the operating system efficiency(OSE)

Need to provide Heat Balance test for verification of the accuracy of M&V instrumentation

III. Indoor environmental quality

Need to conduct full IAQ audit 3 yearly

IAQ audit need to be performed by an accredited laboratory under Singapore Accredited Council

IAQ audit need to comply with NEA’s Guidelines for Good Indoor Air Quality in Office Premises or SS554:2009 Code of practice for Indoor air quality for air-conditioned buildings

IV. Natural ventilation

Only applicable for GM platinum projects

Only applicable to occupied areas (ie. excluding circulations, plant rooms and transit areas)

Courses conducted by BCA – Green Mark Facilities Manager, Green Mark Manager and Green Mark Professional

 

 

 

 

Car park system

Topic 13

Parking Guidance system

This system provides drivers with a real time indication of the available parking lots, saving time to search for a available lot.  Multiple display boards at various strategic locations will ensure that drivers are directed to the nearest available lots at the shortest available time.

Each parking lot is installed with sensors to send a signal to the parking system whenever a lot is vacant or occupied.  A vehicle detector bar placed at the entrance of each zone updates the display to indicate the available number of lots in that area ensuring that driers can estimate if they will succeed in getting the available lots in that area.  The lot indicator light also enables derivers to locate available lots from distance.

 

 

Lift system

Topic 9

Passenger lift – Elevator equipment consists of:

  1.  the car
  2.  the cables
  3.  the elevator machine
  4.  the control equipment
  5.  the counterweights
  6.  the shaft or hoist-way
  7.  the rails
  8.  the elevator machine room
  9.  the pit

Type of controls

  1. Single automatic pushbutton control
  2. Collective control
  3. Selective collective control
  4. Computerised system control
  5. Adequate Group supervisory control systems

Type of speed control:

  1. Voltage dc motor control
  2. Variable-voltage, variable-frequency(VVVF) ac motor control

Characteristics of VVVF speed control system:

  1.  Overall system efficiency is high at all motor speeds
  2.  Traction motors used are economical single-speed squirrel-cage
  3.  Motors are 10% to 15% smaller than other drive systems
  4.  System power factor is close to unity
  5.  Speed control and levelling are equal to detraction motor control
  6.  Equipment is 98% solid-stat, thus requiring minimum maintenance
  7.  Electric energy use and peak loads are reduced, thus reducing electric billings up to 35%

Lift homing

When the fire alarm is activated, the lifts home to the designated (usually)  1st floor and park there with the lift landing doors remaining opened, light and ventilation fan off.

In the event of power failure or power interruption in the building, lifts connected to the building standby generator will:

  1. Automatically switched over to the emergency power supply from the generating plant
  2. The lifts will be brought to the designated floor and park there with the lift landing doors remaining open unit all the lifts have been brought down to the designated floor with light and ventilation off.
  3. Thereafter, one or more lifts may resume operation depending on the capacity of the emergency generating plant, in addition to the fire lift.
  4.  Normal operation of the lift shall be automatically reset on the return of normal power supply.

In the event of power failure or power interruption in the building, lifts that are not connected to the building standby generator but installed with Automatic Rescue Device (ARD) will permit the lifts to move and park at the nearest lift landing floor with the lift/landing doors in the opened position, light and ventilation off.

Homing of lifts to the basement storeys are not permitted.

In any public building or part thereof, in which the habitable height exceeds 60m, the emergency power supply should be sized and arranged such that:

  1.  at least one lift (other than the fire lift) with access to every floor or
  2. one lift from each vertical zone if the lifts are arranged to serve different zones in the building

and shall remain operative in the event of power failure or fire.

A manual overriding switch with the same function as the Fire Switch shall be provided for each of the above designated lifts.

Sources: From SS CP 2 Code of practice for installation, operation and maintenance of electric passenger and goods lifts, Code of practice for fire precautions in building and SIM university – School of Science and Technology note

 

 

 

 

Emergency voice communication system

Topic 7

There are two types of voice communication systems found in the building and both are centrally controlled and monitored from a Fire Command Centre within the building

  1. One-way voice communication system -eg to broadcast for emergency situation such as fire alarm activation, mass evacuation, chemical attack, etc
  2. Two-way voice communication system – eg to contact maintenance staff during emergency situation

The one way voice communication system consist of equipment set such as microphone input(press talk-to-talk button), selector switches, amplifiers, tape recorder and loudspeakers.  The loudspeakers  shall be installed at the following locations:

  1.  habitable rooms
  2.  basement areas
  3.  escape staircases
  4. staircase lobbies and lift lobbies forming parts of the escape means
  5. the main entrance lobby
  6. corridors leaking to exits
  7. service areas where people may be working
  8. areas of refuge
  9. assembling areas
  10. lift cars
  11. any other locations as may be required by the relevant authority

The minimum sound level in the area covered shall be at least 10dBA above the ambient noise level.  It shall be not less than 65dBA and not more than 105dBA.

The two-way communication system shall be of independent of all other communication systems within the building and consist of master handset, selector switches at the control console and remote handsets installed at various designated important locations such as:

  1. Fire fighting mechanical equipment rooms such as chiller room, fire protection pump rooms,
  2. Air-handling unit  room
  3. Lift machine rooms
  4. Lift cars
  5. Any other locations as may be required by the local relevant authority.

Sources:  Further details, please refer to the SS546:2009, Formerly CP 25:1999 – Emergency voice communication system in buildings

 

 

 

Domestic water supply and sanitary drainage systems

Topic 4

I. Sanitary drainage system

The design of a sanitary pipe work system should be able to carry away the foul water with the minimum amount of pipe work from the building quickly and smoothly.

The code of practices allow the following design and practices:

  1. Single stack system for residential buildings up to 6 storeys
  2. Ventilated stack system for buildings up to 30 storeys
  3. Fully ventilated system for buildings up to 6 storeys with 7 storeys or more

The maximum distant from the discharge stack to the discharge pipe of the furthest or last appliance should be of 2.5m and the maximum nos. of discharge pipes connected to the discharge stack should be 2.  There should be a minimum of 225mm between the discharge pipe and the cross vent connection points. The uppermost main discharge stack (open roof top) should be installed at a minimum distant of 3m away from any window or opening adjoining the building. The main discharge stack should be at least 150mm throughout the whole length.

The sanitary appliances and fittings connected to the sanitary drainage system are:

Water closet pan, flushing cistern, urinal, flush valve, automatic flushing devices, bidet, special sanitary appliances subjected to approval from PUB, floor trap and floor waste.

The urinal and floor traps need to be vented to prevent water siphoning.  The purpose of venting the floor trap is to prevent the water siphoning so that a water trap or seal is formed at the bottom of the floor trap.  Water seal or trap is to prevent foul smell and insects from entering the building through the sanitary drainage system.

Generally, there are 2 types of sanitary appliances connecting to the soil waste drainage system.  They are:

Soil sanitary appliances – For the reception and discharge of excretory matters.  Examples are: WC, urinal and bidet.

Soil sanitary appliances should have at least one trap with a water seal of not less than 50mm before connecting to a separate branch drain-line to an inspection chamber at level 1 or to a discharge pipe on upper story level.

Waste sanitary appliances – For the reception and discharge of water for cleaning or culinary purposes.  Examples are: Sink, basin, bath and shower.

Sources – From SIM University – School of Science and Technology note

Further details – Refer to the local Sanitary Plumbing System, code of practice on sewerage and sanitary works, 2000

II.  Domestic water supply system

There are 3 modes of water supply for a building based on local requirements:

  1. The level of highest fitting below 125m reduced level with direct water supply
  2. The level of highest fitting above 125m reduced level but below 137m reduced level with indirect water supply through high level storage tank
  3. The level of highest fitting above 137m reduced level with indirect water supply through low level with pumping (transfer pump and tank) to high level tanks

The storage capacity of the high level tank should be sized to be equivalent to the one day’s water requirement. If the storage capacity is more than 5,000 litres, the tank shall  be compartmentalised with balancing pipe and valve so that each tank is able to be isolated for cleaning and inspection without interfering with the supply of water. For tall building, fittings should not be subjected to pressures greater than 35m head. For water tank, the overflow pipe should have an internal diameter larger than that of the inlet pipe. The overflowing level of the overflow pipe should be below the invert of the inlet pipe at a vertical distance of not less than the diameter of the overflow pipe. A warning alarm will be activated when the water reaches a level of not less than 50mm below the invert of the overflow pipe.  Storage tank shall have a water line set at a vertical distance of not less than 25mm below the warning alarm level.  The pump should be powered by the emergency power source switchboard.

Sources from the SIM university – School of Science and Technology note and for further details, refer to the CP48 Code of Practice for Water Services

Domestic water supply storage and water transfer tanks:

  1. Both are installed with ball float valves and water sensor electrodes for high rise building.

The ball float valve is to control the amount of water entering the tank to prevent water from overflowing from the overflow outlet.

2. The water sensor electrodes which are installed in the water tank and are connected via the cables to the float relays are used to activate the domestic transfer pump when water level falls below the set level and cut off the pump when the water level rises to the required level.

3. The water sensor electrodes and relays are also used to cut off the pump when the water level is below the low or above the high set level points to prevent the pump from running dry and water from overflowing from the overflowing outlet.

 

 

 

 

 

 

 

 

 

 

Scope of works

Topic 25

Scope of work for the quotation can be developed using the specification of the equipment or vendor come up with a initial quotation, eg

  1. To supply and replace 1 no. of exhaust centrifugal fan, Model ABC101, single phase 240V, 50Hz, 1500 rpm, 250mm dia, for the male toilet at level 5
  2. To cut and open access opening of the false ceiling c/w reinstatement and painting
  3. To clean up working area and dispose debris from site
  4. To test and commissioning the equipment upon completion
  5. Back with 1 year warranty against workmanship and part – For quotation

Common terms used.

To supply and install – for new item

To supply and replace – for existing item

Submission of fan curve, motor and pump capacity, 1 phase or 3 phase, 50 Hz frequency, flow head, flow rate, IP 65, IP 55, work permit, contractor name list, risk assessment, method of statement, insurance of 2 million, etc

Fire rated door, odourless paint, work carried out after office hour, noisy work only be allowed after office hours, scissor or boom lifts, show round date and time, invitation to quote, tender closing date and time, etc