If duct cleaning

If duct cleaning is determined to be the best option: 1. Hire a duct cleaning contractor who is a member in good standing of the National Air Duct Cleaning Association. Duct cleaning companies must meet strict requirements to become NADCA members. Among those requirements, all NADCA Members must have certified Air System Cleaning Specialists (ASCS) on staff, who have taken and passed the NADCA Certification Examination. 2. PROTECT building occupants during and after duct cleaning: • Place a filter over supply and return grills to capture dust when HVAC system is placed back into service after cleaning. • Perform duct cleaning during hours when the building is unoccupied, such as nights and weekends. • Use containment barriers and proper ventilation equipment, such as “negative‐air” machines equipped with high‐efficiency filters. • Avoid the use of biocides and sealants. Even EPA‐registered biocides may pose health risks, including eye, nose, and skin irritation. • No biocides are currently EPA‐registered for use on fiberglass duct board or fiberglass‐lined ducts. Both the EPA and NADCA recommend replacing wet or moldy fiberglass duct material.

High Level

High Level Ventilation Canopy Cleaning
1  Operatives to check all PPE, cleaning equipment and chemicals required for the task. Refer to COSHH assessments supplied for chemicals being used. Operatives to set out all ‘Caution/Warning’ signage required and cordon off cleaning area prior to work commencing.
2  Operatives are reminded that canopies can be fragile or may have loose screws or bolts, seams can be broken and surface dented or misshaped.
3  Operatives to erect access equipment e.g.. stepladder or ladder in the correct and safe manner. Ladders to be erected at the correct angle of 1:4 (75º). If working between 2-6 metres height ladders must be footed or an approved ladder stopper or stabiliser used.
4  Operatives to take care if leaning ladder on to canopy cover, if possible position ladder on to nearest solid surface instead, e.g. wall.
5  Operatives to wear tool belt with all tools attached, this will leave both hands free for climbing and descending ladder or step ladder. Operatives are reminded not to climb above 4 rungs from the tops of ladders or step ladders.
6  Operatives to clean canopy using the correct chemical on a clean cloth  or  ‘Greenie’.

surface or cause

surface or cause panels to fall out of the framework. Ceilings may be badly stained, be old or have poor quality surfaces, therefore do not use any other chemicals other than the chemical stipulated, as this may strip the surface or leave streaky marks. If any panels are damaged or fall out during cleaning immediately inform the Supervisor.
7  Operatives to spray chemical on to an area of approx. 1m2 and allow to soak for a few minutes. Repeat this process in a methodical manner working across the ceiling. Operatives to take care when cleaning false ceilings to clean right up to and including edges of support framework. Note: do not over spray as this will cause streaky marks and drip on to the floor.
8  Operatives to use a clean cloth or ‘Greenie’ (if the surface allows) to wash each area in turn, an extension pole with cloth or ‘Greenie’ fitted may be used if necessary.
9  On completion of cleaning, operatives to dispose of all waste chemicals and materials on site and remove all cleaning equipment, chemicals and signage to company vehicle.
10  Operatives are not to leave the site until authorised by Supervisor.

demand is being

demand is being addressed by firms who market air duct cleaning services. Because barriers to entering the air duct cleaning business are minimal and uniform standards of professional practice have yet to be adopted, anyone with an interest can enter the field. This has permitted firms to spring up with controversial techniques. This is not to say that most duct cleaning businesses are unethical. Companies are seeking the best solutions for each individual home with contamination problems. They are looking for new and better ways to serve a very troubled clientele. The clientele is also wary because little is known about duct cleaning. What is the best source of information for consumers about air duct cleaning? Unfortunately, since there are few or no published papers by independent researchers, most of the information available is from people associated with the air duct cleaning industry. Since air duct cleaning procedures have evolved mostly from trial and error as unique and creative solutions have been sought, there has been considerable confusion in the minds of consumers who fear or who are experiencing indoor air quality problems. Here are some insights gleaned from a publication, Indoor Air Review1. The articles have all been written by people involved with firms specializing in air duct cleaning, filtration, and consulting.

TESTING METHODS AND EQUIPMENT

TESTING METHODS AND EQUIPMENT There are two main methods of testing. The pressurization subtraction method utilizes a pressurization unit (i.e. a high-powered fan set up in a doorway and connected to pressure gauges) to pressurize first the entire space that is heated and/or cooled and then the same space with the duct system blocked off. This method is less accurate than the duct testing method. The duct testing method uses a calibrated fan that gently pressurizes the ducts and measures the airflow through the ducts to indicate total leakage. The duct tester consists of a portable fan with calibrated digital pressure gauges that is connected at the blower compartment of the air handler, or attached to the main return grill. All of the duct registers and grills are temporarily sealed, and the duct tester fan is turned on to pressurize the system. The fan pressure is read from the gauges and converted to an equivalent duct leakage rate in cubic feet per minute (cfm). If the amount of air loss falls outside acceptable limits, sealing will be required to correct the condition. This method of testing is preferred, because it measures low airflow accurately, and simulates what takes place under normal operating conditions.

Calculation of acoustic

Calculation of acoustic power is based on measurement of sound pressure level and reverberation time of the testing room. Because it is necessary to measure the level of sound pressure, a low level of a background noise is an essential requirement to be able to offer the best testing results. To achieve this, the reverberation rooms are isolated from the surroundings by a double wall. The first wall is of a heavy construction, so an optimum isolation is ensured against aerial noise. The second wall (interior of the reverberant rooms) not only improves the isolation by providing more mass to the construction; its design also gives rise to a very wide sound field (an essential condition for the correct calculation of the sound power level from the sound pressure level).
First, an enclosure was built to form the perimeter of the exterior rooms. Then the inner walls of the reverberation rooms were raised to favour the diffusion conditions in the sound field. Between both structures, an acoustic insulation material was installed; see Figure 1.

1000 inhabitants).

1000 inhabitants). Sales in other European countries are less than 0.1 heat pumps per 1000 inhabitants.
In 2001, of the total sales in Europe of 41,000 ground-coupled heat pump systems, 27,000 were installed in Sweden. For the next 3-5 years, market growth rates have been estimated by industry as shown in Table 2.
Table 2: Ground-coupled heat pump market Europe.
Country Sales 2001 Growth, %
Austria 4,800 8 Czech Republic 350 25 Denmark 150 >100 Finland 1,250 10 France 850 10 Germany 3,600 20 Netherlands 400 >25 Norway 650 10 Poland 500 5 Sweden 27,000 6 Switzerland 2,800 6 UK 150 >100

encouraging

encouraging to see that there is a growing interest in applying energyefficient technology in developing countries and economies in transition. Although costs are an obstacle for applying modern technology, the industrialised world seems increasingly prepared to look for new ways of information and technology transfer to these developing parts of the world.
How important are heat pumps in relation to the environment? Any thermodynamic specialist or heating/ cooling engineer will have no problem in quickly answering this question. The numbers on COPs and SPFs as well as specific CO2 emission levels are available and can lead to only one conclusion: an increasing application of heat pumps without delay is very important

The IIR

The IIR has prepared the Refrigeration Sector Achievements and Challenges Report for the Johannesburg World Summit on Sustainable Development on August 26- September 4, 2002. The report, titled “Industry as a partner for sustainable development”, is one of 22 sector reports prepared under the auspices of and facilitated by UNEP. For each sector, the overall achievements and limits for the three main dimensions of sustainable development, i.e. social, economic and environmental, are described in depth and future challenges are outlined. The IEA Heat Pump Centre has contributed to the sector report drafting process. The economic scope of the heat pump sub-sector has been estimated at USD 17.8 billion of annual sales. At the launch meeting of the report on May 15, 2002, IIR Director François Billiard stressed that reducing the gap between industrialised and developing countries in terms of the availability of refrigeration equipment, knowledge and training, will undoubtedly be the main refrigeration sector challenge in years to come

Responsibilities

Responsibilities
Distributor Responsibilities. Distributors participating in the energy right Heat Pump Plan are responsible for the following: • Arranging for all program-required inspections • Coordinating QCN member participation with TVA Customer Service Center personnel. If the distributor believes a QCN member participating in the program in their area has violated program criteria, the distributor may collect any evidence to support the claim, and may present such evidence to the appropriate Customer Service Center TVA personnel • Notifying all QCN members participating in the program in their service area of how the heat pump program will operate in their area, if any incentives or rebates are available and what percentage of inspections will be performed
Contractor (QCN) Responsibilities. TVA will maintain a list of heat pump contractors who apply and qualify for membership in the Quality Contractor Network (a group of contractors listed by TVA).  Only QCN members shall participate in the energy right Heat Pump Plan.
If a QCN member, or representative, has any questions about weatherization measure(s), installation criteria, inspection procedures, or forms, the inspector should be notified prior to installatio

members are responsible for:

QCN members are responsible for: • Determining if the dwelling or  business is a good application for the installation of a heat pump, which may include the condition of the structure as well as living habits of the residents; for example, a home in obvious need of extensive structural repair would not be a good application • Determining the legal owner of the dwelling prior to applying for program financing • Ensuring that the installation of the heat pump does not alter the structural integrity of the dwelling • Informing customer, preferably in writing, of details about the heat pump installation prior to beginning work, including: − type of equipment and accessories − weatherization work required − location of heat pump units − location of registers, return air grilles, thermostats, ductwork, etc. − alterations to home − time frame for installation

Requirements section,

Requirements section, item 2, utilizing the manufacturer's published capacities for an entering water temperature of 90°F (cooling); however, the total cooling capacity shall not be more than two times the total cooling load. The gallon per minute flow rate shall be within the range specified by the manufacturer. − Earth Coil Design ⇒ The earth coil shall be sized and installed as recommended by the "Closed Loop/Ground-Source Heat Pump Installation Guide" and the "Ground Source Systems: Design and Installation Standard" by the International Ground Source Heat Pump Association. The earth coil design length shall satisfy the heat gain or heat loss, whichever is greater, for the structure. ⇒ The final earth coil design shall be determined by the QCN member, equipment distributor, and/or heat pump manufacturer. A computer printout (or equal) and sketch of the earth coil layout shall be available for review at the request of the inspector. − Earth Coil Installations ⇒ Earth coils may be installed in either parallel or series. When parallel coils are used with a reduced header design or a reverse return header design, the total effective length of the individual loops shall be within 5 percent of each other to ensure balanced fluid flow through the loops. ⇒ Pipes entering the building through a foundation wall or floor shall be sealed and/or protected. The pipes shall be contained in a sleeve to protect them from chafing on the floor or wall as they expand and contract. If the possibility of ground water seepage through the opening exists, the area around the piping shall be protected and sealed

Determine cooling capacity

Determine cooling capacity by using the following formula:  Btuh = (h2 - h1) x 4.5 x CFM   h1 =  heat content of air from Enthalpy Table corresponding to supply air  wet bulb temperature.*  h2 =  heat content of air from Enthalpy Table  corresponding to return air wet bulb temperature.*  4.5 =  air properties constant  CFM =  cubic feet per minute air calculated, from funnel, temperature rise, or return air method  *   At supply air outlet and inlet indoors record wet bulb and dry bulb temperatures.   (From Enthalpy Table record heat content values that correspond to supply and return air wet bulb temperatures, h1 and h2, respectively) − Verify that system capacity is ± 10% of the equipment manufacturer's rating at the test conditions.
Procedures for Notifying Customer and QCN member of Failed Inspections
When a program required inspection of an installation is made and the installation is not in compliance with program standards, the Inspector will indicate on the Heat Pump Installation Inspection Checklist (TVA 6254T) and on the Work Completion/ Form (TVA 6254T-1) (where applicable) the reason(s) for the failure to pass the inspection. The QCN member may be allowed to correct minor deficiencies while the inspector is on-site. Customer and QCN members must receive a copy of Heat Pump Installation Inspection Checklist. All deficiencies must be corrected and be in compliance within 10 business days. Following corrections by the QCN member, the inspector shall be notified, after which a reinspection shall be scheduled and performed. If, during thi

Existing Conditions

Existing Conditions—The QCN member shall be responsible for determining if the installation of additional floor insulation will cause structural damage to the residence. If applicable, QCN members shall notify inspector and customers prior to installing insulation if they determine that an R-value different from that recommended should be installed.  The QCN member shall be responsible for completing all preparation work involving insulation materials already existing in the residence, such as blocking around heat-dissipating devices that were covered with existing insulation, etc.  The customer shall be responsible for seeing that preparation work such as repairing the floor, foundation wall leaks, pipe leaks, vent leaks, removing objects stored in the crawl space area, etc., is completed if failure to do so would adversely affect the installation of additional insulation. • General Requirements − Cross Bracing. Batts and blankets shall fit snugly against the floor joists, cross-braces, headers, and adjacent batts or blankets. Gaps between floor joists and insulation caused by carpenter error or warped joists shall be stuffed with insulation to reduce energy loss. Batts or blankets shall be cut and split in such a way as to fit between any cross-bracing if looping under the cross-bracing will require more than one-third of the batt or blanket to extend below the floor joists. Any method other than cutting and splitting at the cross-bracing must be approved by TVA.  − Heat Dissipating Devices. Insulation materials shall maintain a minimum 3-inch clearance from heat dissipating devices such as furnaces and electric motors; also the insulation material shall be prevented from blocking or restricting combustion air openings of gas or oil-fired furnaces. − Underfloor Protection. Insulation materials in open underfloor areas shall be protected from the weather and other hazards by fastening (stapling) a minimum 6-mil thickness polyethylene to the bottom of the floor joists perimeter inwards 2 to 3 feet. In addition, the floor insulation shall be supported by poultry netting or nylon mesh beneath the entire floor to protect it from destruction by animals.  − Crawlspace Vents. Proper crawl space ventilation, as discussed in these standards, shall be installed if needed. The insulation shall not cover or block the ventilation system in any way.  − Exhaust Vents. Clothes dryer and other exhaust vents shall be vented to the outside. • Vapor Barriers—An acceptable floor vapor barrier shall be installed toward the winter-warm side of the insulation. − Approximately 80 percent ground coverage is recommended for existing homes (one year old or older). In placing the vapor barrier over the underfloor surface, the adjoining edges shall be

Check cabinets for prope

Check cabinets for proper alignment and any unnecessary holes.  Holes allowed are for the manufacturer's approved internal condensate drain system (condensate drain lines shall be sized in accordance with the manufacturer's recommendations and all instances at least as large as the heat pump's drain connection). (Major)
k. Ground Water Source Heat Pump (GWSHP) and Earth Coupled Heat Pump (ECHP) Inspection Procedures Inspect GWSHPs and ECHPs and duct system(s) for adherence to Standards The preceding inspection procedures shall apply to both GWSHPs and ECHPs except as follows:
1) Check GWSHP and ECHP for installation of pressure/temperature (P/T) test ports installed in the "water-in" and "water-out" piping runs at the unit.  The P/T test ports shall be as close as possible to the heat pump. (Major)
2) Check system heating capacity as follows: (Major)
a) Allow heat pump system to operate for at least 15 minutes.
b) Measure water pressure drop (PD) between water-in and water-out test plugs at heat pump. (Use same instrument to measure both to reduce error).
c) Measure entering water temperature at water-in test plug.

Payments. TVA

Payments. TVA will pay MVP by Electronic Funds Transfer (EFT) or a mutually agreed upon alternative arrangement. Payments will be based on heat pump installations successfully entered in the energy right Program data base, which have not been previously paid. • Amount of MVP—The distributor will be paid for heat pumps meeting all requirements in the energy right Program agreement according to the current payment plan (Schedule HP). MVP is based on efficiency. • Adjustment of Payment Rates—When the payment rate is adjusted, the distributor will be informed of the adjustment and its effective date. After the effective date of any adjustment in the payment rate, the distributor will have three months to inspect and qualify any installations committed to prior to the effective date of the adjustment as evidenced by documentation confirming the date of that commitment. Payment Procedures. Distributors apply for payment by submitting a Work Completion Form to TVA’s database. Documentation. The distributor shall maintain files containing information for each participant in the energy right Heat Pump Plan. At a minimum, distributor records shall include the following: • A completed Work Completion/ Form indicating the size, type, etc., of each heat pump. • A Quality Contractor Network (QCN) member invoice providing the brand, type unit, rated capacity, and serial and model numbers of the equipment installed. Financing If a distributor has selected financing for the Heat Pump Plan, see Article X for requirements and procedures. Financing is limited to heat pump equipment and accessories and associated weatherization as listed in the Financing Section of the Reference Materials for existing dwellings only. At this time, there is no financing for the business application.

"Liquid" sensor

"Liquid" sensor This is in the liquid line of the outdoor coil. It begins the defrosting cycle after a period of 30, 60 or 90 minutes (as selected) has elapsed from the start-up or since the previous defrosting, when the temperature detected drops to -5°C or less. It stops the defrost cycle when the liquid temperature reaches 13°C or stays at a minimum of 7°C for at least 5 minutes. It prevents defrost in mild climates when it does not detect a sufficiently low temperature. The reading for the beginning of defrost of 30, 60 or 90 minutes is nominal. These periods are based on an outside temperature of 2°C, a highly unfavourable level which causes considerable frost formation. At lower temperatures the overall humidity content of the ambient air is lower, making it possible to postpone the defrost cycles, thus saving energy. For example, at -10°C outside temperature, the reading times for the beginning of defrost will be 60, 90 & 120 minutes. Balance point It prevents functioning of the support system when the outside temperature is higher than the balance point as adjusted on the plaque. In this way, we save the heater's functioning as long as the heat pump is capable of satisfying the building's requirements. The balance point can be adjusted between 14°C and -4°C. This avoids the necessity of fitting an additional outside thermostat.

Input to the calculation

Input to the calculations is the COP and capacity of the heat pump tested at four-five different temperature levels +12°C, +7°C, +2°C, -7°C and -15°C (-15°C is only required for the colder climate). The heat pump shall be tested in equivalence with standard EN 14511:2007, with the same test methods, test set up, uncertainty of measurements and the way of evaluating data. The heat pump shall be tested at part load to deliver the required heat load of the building at each temperature level. Instructions of how the heat pump shall be tested by means of part load and type of operation; fixed capacity units, staged capacity units and variable speed capacity units, are given in this method. The required part load for the building at the test points are given by:

determined in various ways,

Figure 1. SPF can be determined in various ways, including field measurement, calculation methods and dimensioning software. Based on lab measured performance data, SPF can be calculated according to calculation methods, that normally relates performance data in specific operating modes to annual climatic conditions, expressed as “bin models” where the number of hours in a year the temperature is between certain values are binned together. Model buildings are normally used to give annual heat demands and overall heat transfer resistances of the building. For the installer of heat pumps, more specific details of the building must be prompted, as well as detailed data about the ground properties in the case of GSHP’s. Local climatic data is also used for estimating the heat demand. The climatic data contains a cold shock in order to dimension the heat pump capacity to extreme conditions that may occur during the lifetime of the installation. Other data such as the number of occupants, Domestic Hot Water (DHW) energy consumption is also normally entered in the software models for dimensioning. To evaluate the real performance of the installed heat pump, field measurements are carried out to relate the useful heat produced to the energy input, often electrical power (but it could also be heat driven processes). The SPF of the heat pump is then often expressed as the ratio of the heat delivered to the heat distribution system (including DHW when relevant) to the electricity to operate the heat pump (including electricity to operate pumps and fans to bring the heat source to the heat pump). The different level of detail given as input in the different stages of SPF calculation will lead to different SPF values. The main objective of this project is to identify what needs to be included in a new calculation method in order to better represent the real SPF of the heat pump in the building system

These charts relate

These charts relate duct friction, duct size, air flow in cubic foot per minute and flow velocity.  Reference 2 indicates that duct velocities should be about 900 ft/min or less.   Entering an air friction chart at 2137 ft3 /min flow quantity and a velocity of 900 ft/ min at the air handler outlet, gives a friction loss of .05 inches of water per 100 feet and an outlet duct of 21 inches diameter.  To get the maximum pressure loss in the system, determine the longest run of duct. Inspection of Figure 5 shows that the longest run consists of duct sections A+C+D+F+H+J.  Including the entrance and elbow equivalent lengths, this run length is  L = 10ft entrance +6+6+35ft elbow +10+20+2+35ft elbow +17 = 141 ft The total pressure loss is
© Gary D. Beckfeld  Page 13 of 21
P = .05 (141/100) + .04 in. diffuser loss = .1105 in. of water

Balancing pressures

) Balancing pressures
Within any form of fluid transportation there is always some pressure drop off in the system due to acombination of two factors: •Friction of the fluid moving across the walls of the duct– which depends on flow type,internal face’s geometry and the friction coefficient. •Dynamic drop due to variations in ductgeometry and/or the direction of the air flow.
In order to achieve correctperfusion,ducts musthave a correctly defined section,with a balanced average air velocity and defined static pressure.
Inadequate ductnetwork design or defects in material installation will change the operating conditions,giving rise to thermal loads in the targetareas and insufficientair replenishment(with a decline in perceived comfortfor the building’s occupants).
d) Noise in ductnetwork and acoustic attenuation
Another aspectindependentof material which plays a fundamental role in a ductis acoustic attenuation ofthe noise produced by the HVAC system itself (air handling units,airflow in the ducts,diffusers etc.…),as well as from ‘transmission noise’produced in the building and thattransmitted to neighbouring buildings via the ductsystem.As noise is considered ‘unwanted sound’,itis evidentthatreducing noise results in better indoor air quality & comfort.To achieve the desired level of attenuation,ducts made from or insulated using a material with high acoustic absorption properties,such as glass wool need to be installed. The most effective solution would be based on glass wool ductboards. Alternatively,the application of glass wool ductliners mightalso be recommended.If ULTIMATE mineral wool is to be used,due to fire resistance requirements,italso significantly attenuates noise produced in the installation.The following table shows the results of the studies carried outby NAIMA on ductnoise attenuation for differentducts solutions:

FUNCTIONS

FUNCTIONS
5.1 AUTO POWER OFF
The auto power off helps conserve power when using on battery or the AC adapter,
the machine will automatically turn off after 4 min of inactive use or no change in
the displayed weight.
6.0 CALIBRATION
Before calibrating the Dune series it is best to turn on the unit for about 1 min to let
the components warm up.
1) Press [on/off] key to turn the power on, if it is not already.
2) Press and hold the [Unit] key, until “CAL” is displayed
3) Remove any weight from the pan.
4) Press the [Unit] key, the display will flash “CAL” them will show the cal mass
required. If the cal mass is not displayed then the machine is not stable or is
not within a zero range. Turn off the unit and try zeroing the display before
trying another calibration.
5) Place the appropriate calibration mass on the scale

Supply Outlets

Supply Outlets
2.2.1 Impact on Uniformity
When selecting supply outlets, the designer must consider the “occupied zone” of the space to be
2 feet off walls and 6 feet above the floor to avoid drafts. Drafts caused by airflow within the
occupied zone can be considered a comfort issue. The amount
of airflow that may be perceived as a draft can be relatively
low. Air at a velocity of 15 feet per minute may allow smoke
to hang in the air, whereas a piece of paper may blow off a desk at an air velocity of 65 feet per
minute. The target terminal velocity or the velocity at the useful end of an air stream is between
50 and 75 feet per minute; therefore, if this air stream is directed into the occupied zone, a
complaint of a draft is likely.
Pressure loss associated with the supply outlets must be considered when selecting the type of air
outlet and must be added to the entire duct run pressure loss.
The proper amount of air is determined by the room-by-room heating and cooling loads. Too
little air delivered to a room results in underheating or undercooling, whereas too much air
delivered to a room results in overheating or overcooling. To maintain a uniform temperature
and to avoid stratification, the supply air must also adequately mix the air in the room.

however, where ducts

however, where ducts pass through spaces surrounded by "A" class divisions, without serving those
spaces, provided those ducts have the same fire integrity as the divisions which they pierce.
D.5.7.6 Ventilation ducts with a free cross-sectional area exceeding 0.02 m2 passing through "B" class
bulkheads shall be lined with steel sheet sleeves of 900 mm in length divided preferably into 450 mm on
each side of the bulkheads unless the duct is of steel for this length.
D.5.8 Insulation of duct penetrations
The fire protection insulation of air ducts and sleeves is to be in accordance with the space group pairings
indicated in tables, see GL Rules for Hull Structures (I-1-1), Section 22, Table 22.1 to 22.8.
The tables relating to the bulkhead are likewise applicable to ducts routed through decks.
A space pairing refers to the spaces separated by a bulkhead or deck, irrespective of any other spaces
served by the duct in question.

Where a thin plated

D.5.7.2 Where a thin plated duct with a free cross-sectional area equal to, or less than, 0.02 m2 passes
through "A" class bulkheads or decks, the opening shall be lined with a steel sheet sleeve having a thickness
of at least 3 mm and a length of at least 200 mm, divided preferably into 100 mm on each side of the
bulkhead or, in the case of the deck, wholly laid on the lower side of the decks pierced.
D.5.7.3 Where ventilation ducts with a free cross-sectional area exceeding 0.02 m2 pass through
"A" class bulkheads or decks, the opening shall be lined with a steel sheet sleeve. However, where such
ducts are of steel construction and pass through a deck or bulkhead, the ducts and sleeves shall comply
with the following:
D.5.7.4 The sleeves shall have a thickness of at least 3 mm and a length of at least 900 mm. When
passing through bulkheads, this length shall be divided preferably into 450 mm on each side of the bulkhead.
These ducts, or sleeves lining such ducts, shall be provided with fire insulation. The insulation shall
have at least the same fire integrity as the bulkhead or deck through which the duct passes.
D.5.7.5 Ducts with a free cross-sectional area exceeding 0.075 m2 shall be fitted with fire dampers in
addition to the requirements of D.5.7.4. The fire damper shall operate automatically, but shall also be
capable of being closed manually from both sides of the bulkhead or deck. The damper shall be provided
with an indicator which shows whether the damper is open or closed. Fire dampers are not required

the ducts where they

D.5.4.4 The ducts where they pass through a machinery space of category A, galley, vehicle space,
ro-ro cargo space or special category space are constructed of steel, suitable supported and stiffened
(see D.5.3.1) and
D.5.4.5 Such ducts are insulated to "A-60" standard within the machinery spaces of category A, galleys,
vehicle spaces, ro-ro cargo spaces or special category spaces.
D.5.5 Ducts are to be routed in such a way that neither machinery nor switchgear can be endangered
by condensation or spray water. Where necessary, water traps, baffles and similar devices are to
be fitted. Effective water traps are to be provided with appositely directed baffle plates. The lowermost
baffle of the water trap is to be provided with a drainage pipe.
D.5.6 Natural ventilating systems shall not employ a branched ducting system.
D.5.7 Duct penetrations
D.5.7.1 Duct penetrations through "A" class divisions shall be of an approved type 4. Where steel
sleeves are directly joined to ventilation ducts by means of riveted or screwed flanges or by welding, the
approval is not required.

D.5.3.4 insulated

D.5.3.4 insulated to "A-60" standard from the machinery spaces, galleys, vehicle spaces, ro-ro cargo
spaces or special category spaces to a point at least 5 m beyond each fire damper; or
D.5.3.5 constructed of steel suitable supported and stiffened (see D.5.3.1) and insulated to "A-60"
standard throughout the accommodation spaces, service spaces or control stations.
D.5.4 Ducts provided for the ventilation to accommodation spaces, service spaces or control stations
shall not pass through machinery spaces of category A, galleys, vehicle spaces, ro-ro cargo spaces or
special category spaces unless either:
D.5.4.1 the ducts where they pass through a machinery space of category A, galley, vehicle space, roro
cargo space or special category space are constructed of steel, suitable supported and stiffened (see
D.5.3.1),
D.5.4.2 automatic fire dampers are fitted close to the boundaries penetrated and
D.5.4.3 the integrity of the machinery space, galley, vehicle space, ro-ro cargo space or special category
space boundaries is maintained at the penetrations or

These ducts shall

D.5.1.1 These ducts shall be of any material having low flame spread characteristics which is type
approved 2.
D.5.1.2 On ships constructed on or after 1 July 2010, the ducts shall be made of heat resisting noncombustible
material, which may be faced internally and externally with membranes having low
flamespread characteristics and, in each case, a calorific value 3 not exceeding 45 MJ / m2 of their surface
area for the thickness used.
D.5.1.3 They may only be used at the end of the ventilation device.
D.5.1.4 They shall not be situated less than 600 mm, measured along the duct, from an opening in an
"A" or "B" class division including continuous "B" class ceilings.
D.5.2 Flexible bellows of combustible material may be used for connecting fans to the ducting in air
conditioning or fan rooms.
D.5.3 Ducts provided for the ventilation of machinery spaces of category A, galleys, vehicle spaces,
ro-ro cargo spaces or special category spaces shall not pass through accommodation spaces, service
spaces or control stations unless the ducts are either:

Fire dampers within the duct system

D.4.2 Fire dampers within the duct system
D.4.2.1 Approval
Fire dampers, including relevant means of operation, are to be of approved type 1.
D.4.2.2 Accessibility and indication
Fire dampers shall be easily accessible. Each damper shall be clearly marked by an identification number
or letters. Where they are placed behind ceilings or linings, inspection doors shall be provided. These
inspection doors shall be clearly marked with the relevant identification marks. The identification mark
shall be placed also on any remote control. The status (open/ closed) of each fire damper shall be clearly
indicated at the damper and each remote control.
D.4.2.3 Type of means of manual closing of fire dampers
Manual closing may be achieved by mechanical means of release or by remote operation of the fire
damper by means of a fail-safe electrical switch or pneumatic release (spring-loaded, etc.) on both sides
of the division.
D.5 Ventilation ducts
D.5.1 Ventilation ducts shall be of steels or equivalent material. Short flexible ducts, however, not
generally exceeding 2 m in length and with a free cross-sectional area not exceeding 0.02 m2 need not be
steels or equivalent, subject to the following conditions:

The arrangement of two fire closures o

The arrangement of two fire closures of multi blade design according to D.4.1.4 in a common
frame is acceptable, if the following requirements are fulfilled:
 The total free cross sectional area of the entire ventilation opening is at least 3 m2
 The cross sectional area of each single blade is at least 0.5 m2
 The two fire closures are to be separated from each other. For this purpose an intermediate frame is
to be provided
 The closing mechanism of the two fire closures shall be independent from each other
D.4.1.6 Weather tight closures of a recognized standard are accepted as fire closures. In that case
weathertight closures are to be permanently attached irrespective of the length of the ship.
D.4.1.7 GL approved weather tight closures of multi-blade design, which are use rubber as sealing
material, may be accepted as fire closures if the following requirements are fulfilled:
 The closure is located in a position, where in accordance with Load Line Convention weather tightness
is required
 The closure consist of not more than 5 single blades
 The total clear height of each blade shall be at least 200 mm
 Each blade shall have a thickness depending on its cross section as specified in