EOL Resistor not a Termination Resistor

Early security systems used simple electrical circuits to monitor the status of doors and windows. The circuit was either closed or open, and therefore returned full voltage or no voltage at all to the control panel; that was all the system wanted or needed to know. Although such circuits are still in use today, the digital age gave manufacturers the opportunity to make systems more secure.

A resistor is a small semiconductor which resists the flow of electrical current. The current is permitted to flow, but is reduced by the value of the resistor. If a resistor is connected, in series, with a sensor on an alarm circuit, then the control panel no longer sees full voltage across the circuit, but rather a reduced voltage, when the circuit is closed. Now there are three possible conditions for the control to measure: full open-circuit voltage (if the circuit is open), reduced voltage (if the circuit is closed and secure), and no voltage if the wiring has been compromised. For if the two sides of the circuit are making contact at some point between the control and the resistor, the current has a shortcut back to the control, thus bypassing the resistor. The control will see this no voltage (or very low voltage) as a fault and will alert the user.

In fire alarm and security systems, at the end of the input circuit (Initiating Line Circuit or IDC), and at the end of the output circuit (Notification Appliance Circuit or NAC), there's an End-of-Line Resistor. 

Both the Terminating Resistor and the End-of-Line Resistor (EOL) are across the conductors at the end of the circuit. 

The difference between the two types of resistor, though, is not where they're at or even what they're made out of. They're both at the end of the line, and both across the conductors. They can even come out of the same package from the store or distributor. 

The difference between the two is why they're installed at the end of the line. 

Terminating Resistor

In signal carrying systems, especially between equipment like between the TV camera and the video recorder (Closed Circuit TV or CCTV), or an RF amplifier for a Master Antenna TV (MATV) system and the TV set, there's a Terminating Resistor. 

On a Video Input, inside the DVR (Digital Video Recorder or Security Recorder) there's a Terminating Resistor. 

With Master Antenna TV (MATV), the Terminating Resistor is at the last "tap" when several taps are used in a single line from the amplifier. 

When the TV set is at the end of the line for the MATV system, inside the TV set there's a Terminating Resistor. 

For a true RS485 communication control circuit, there's Terminating Resistors at each end of the daisy-chain. 

Purpose of the Terminating Resistor

A Terminating Resistor is a Signal Quality component. It is used to soak up an AC signal, preventing reflections or ghosts on the line. 

It takes time for signals to travel along wire, and the energy of the signal cannot be created or destroyed; it has to go somewhere. At the end of the line where the wires end, if the wire is just cut off, the signal hits the end of the line and bounces straight back. 

If the wires at the end are shorted together to prevent the bouncing straight back, the signal takes a U-turn and returns in reverse voltage. 

Because of the time it takes for the signal to travel to the end of the wire and back, the bounced back signal is an extra, unwanted signal on the line. It degrades the video or control signals, or if the wire is long enough even returns as an extra erroneous video or control signal. 

The value of the Terminating Resistor is chosen very carefully to be able to soak up this signal when it reaches the end of the line so the signal doesn't bounce back. 

End-OF-Line Resistor

The End-of-Line Resistor used in fire alarm systems and security systems may look the same as a Terminating Resistor, however the function of the End-of-Line Resistor is completely different. 

The "End-of-Line Resistor" confirms that the wiring in a building remains undamaged. It's across the end of all the wire in each pair of wires (loop) for all inputs (Initiating Device Circuit or IDC) and outputs (Notification Appliance Circuit or NAC). 

Purpose of the End-of-Line Resistor

As opposed to the terminating resistor, which is there to prevent signal reflections, the End-of-Line Resistor is a Life-Safety and Property Protection component. 

It's important to understand that the "signals" used in fire alarm systems are DC, either on or off, not AC, which carries information like video or data. 

Because there's no AC, there are no reflections from the end of the loop; the End-of-Line Resistor is used to pass DC current. 

The only purpose is to pass a small supervision current so the fire alarm or security panel can "look" at the wire; if the supervision current stops, the stoppage can be reported immediately, and the trouble fixed, before there is a real fire. 

The End-of-Line Resistor versus the Terminating Resistor

So the Terminating Resistor of RS485 control wiring or coax cable is used to soak up AC signals, while the End-of-Line Resistor of the fire alarm or security system loop is used to pass DC current. 

Smoke detectors at home under Code

Making Sure you’re home under Code

Smoke detectors are mandatory for new homes at Singapore from June 2018. Confirming this move for the first time since it was flagged by The Straits Times in August, Second Minister for Home Affairs Josephine Teo said the smoke detectors will provide residents with early alerts to smoke or fires. "Residents can take steps to quell the fire and prevent it from spreading, or if that is not possible, to quickly evacuate," said Mrs Teo, who is also Minister in the Prime Minister's Office and Second Minister for Manpower. She was speaking at the Fire Safety Asia Conference Singapore Nov, 2017.

For multi-storey homes, each floor will need at least one device, and floors with combined living and dining room spaces of more than 70sqm will require at least two.

Home owners can install even more smoke detectors - but not in kitchens and toilets, where smoke and steam from cooking or bathing could trigger false alarms.

Existing homes that undergo fire safety works after June, such as renovations involving a fire-rated door, will also have to follow the latest fire code and have smoke detectors installed.

However, the Singapore Civil Defence Force (SCDF) requires them to be compliant with either European, Australian or American standards for fire alarms, it said in a press release yesterday.

The cost of installing the detectors in new homes will be borne by developers, while owners of existing homes will have to pay for them.

To help needy residents, SCDF, HDB and the People's Association will install smoke detectors for about 50,000 households in public rental flats for free, in phases.

Priority will be given to households with at least one elderly person aged 60 and above.

Mrs Teo said the ageing demographic of residents was an "important consideration" when updating the Fire Code, which is currently in its seventh edition.

She encouraged existing home owners to also install smoke detectors, even if they are not required to do so.

"HDB will be installing (smoke detectors) in many of its ongoing public housing projects even though these new projects al-ready have building plans sub-mitted before June 2018. I hope, of course, that many private developers and existing home owners do likewise."

One public housing project, Kampung Admiralty, an integrated development for the elderly, already features fire alarm devices connected to a central alarm system.

We all know that having working fire/smoke detectors, alarms, and fire extinguishers in our homes can prevent tragic loss and irreparable damage.  The same holds true for business facilities.  However, the codes and standards for a commercial space versus a home are different, and they can vary by jurisdictions as well.  According to the NFPA(National Fire Protection Association) codes are the rules and standards are the method by which the rules are applied.  There have been major events in history that have triggered modifications to national fire codes and standards.  The Station Nightclub fire in West Warwick, RI in 2003, and The Cocoanut Grove Nightclub fire of 1942 in Boston, MA are a couple examples of why and how fire codes have changed throughout the years.

If you are a business owner, you know the importance of protecting your facility, employees, and assets/inventory.  How can you be sure your business meets the proper fire safety codes?  In all likelihood, if you’re currently in operation, your building/facility has passed an initial inspection.  However, yearly inspections are required and codes are revised every 3-5 years.  If you are renovating or adding on to a space you will have to schedule a new inspection.  For this reason its best practice to involve an expert from the start of a project to avoid any major hiccups.

You’ll need the proper fire safety equipment which can include smoke detectors, fire alarms, carbon monoxide detectors, and possibly a sprinkler system.  Integrating these features with your alarm system is crucial for a quicker response from emergency services.  Installing a wireless smoke detector that is not connected to your alarm system doesn’t notify local services in the event of an emergency.  The only person that type of detector benefits is someone on site or nearby during an emergency.  What if no one is around? 

Failure to comply with the proper safety and code requirements can lead to inspection rejection and fines.  Some licensed professionals at market. They can ensure the safety and code compliance of your business by installing the proper fire safety equipment as part of a comprehensive business security system.  Please find out authorized team, they can guide you through the process from initial assessment to final installation.  You have enough on your mind already, let us help you avoid mental anguish.

Reasons For Code Non-Compliance:

·       Egress is not met. This includes corridors, latching mechanisms, and access controls

·       Improper storage of combustible materials

·       Inadequate emergency lighting

·       Outdated fire extinguishers and other safety equipment

·       Electrical issues (i.e. improper use of extension cords)

·       Blocked access to fire hydrants

·       Sprinkler system isn’t labeled correctly

How Hiring A Professional Can Help:

·       They know what types of security equipment will work and comply with fire codes

·       They may already have a relationship with the local fire official

·       They can communicate technical information to contractors, architects, & engineers

·       They know how to integrate fire alarms and smoke detectors in a comprehensive security system

·       They understand the importance of code compliance and fire safety

·       They know how egress can be affected by different access controls

·       They will help you avoid penalties and failed inspections by implementing proper installation

The new code will also make it mandatory for non-residential buildings with large unmanned premises, such as warehouses, to have a video image fire detection system.

This smart system uses video analytics to detect smoke or fire, allowing building owners and fire safety managers to quickly confirm the presence and extent of a fire.

Upcoming changes NFPA 1 in 2018

Upcoming changes NFPA 1 in 2018 edition, minimum fire prevention inspection frequencies for existing occupancies

Looking back, one part of the Code that I don’t spend a lot of time talking about, but should, is how it is applied and how it is enforced.  Practically speaking, when does one even use a Fire Code?  Who needs to know how to enforce it?  When is it enforced? How often does the fire inspector, responsible for the enforcement of NFPA 1, need to inspect a building for fire safety provisions? These administrative requirements and general provisions, as contained in Chapter 1, Chapter 4 and parts of Chapter 10, provide the fundamental provisions for those responsible for its application and enforcement.  Compliance with these requirements is critical to the effectiveness of NFPA 1.

NFPA 1 is applicable to both new and existing occupancies.  Per Section 10.1.1, every new and existing building or structure shall be constructed, arranged, equipped, maintained, and operated in accordance with this Code so as to provide a reasonable level of life safety, property protection, and public welfare from the actual and potential hazards created by fire, explosion, and other hazardous conditions. I highlight the words constructed and maintained to emphasize how the Code plays a role in a building during both construction of the building as well as maintenance throughout the life of the building. The enforcement of a building does not stop once its construction is complete and a certificate of occupancy is received. 

New to the 2018 edition is Section 10.2.7 which prescribes the minimum fire prevention inspection frequencies for existing occupancies.

This Section was added, in part, to recognize the publication of new NFPA 1730, Standard on Organization and Deployment of Fire Prevention Inspection and Code Enforcement, Plan Review, Investigation, and Public Education Operations, and in addition, to provide guidance to AHJs and inspectors for ensuring existing occupancies remain in compliance with the fire code. Section 10.2.7 reads as follows:

10.2.7 Minimum Fire Prevention Inspection Frequencies for Existing Occupancies.

10.2.7.1 Fire prevention inspections shall occur on existing premises in accordance with the minimum inspection frequency schedule specified in Table 10.2.7.1. [1730: Table 6.7]

10.2.7.2 Where required or permitted by the AHJ, the required fire prevention inspection shall be conducted by an approved party that is qualified in accordance with NFPA 1031.

10.2.7.3 The AHJ shall be permitted to approve alternative qualifications for the approved party specified in 10.2.7.2.

10.2.7.4 The provisions of 10.2.7 shall not apply to detached one- and two-family dwellings or townhomes.

NFPA 1730 contains minimum requirements relating to the organization and deployment of code enforcement, plan review, fire investigation, and public education operations to the public.  The addition of new 10.2.7 incorporates the standard of care, as specified in NFPA 1730, into NFPA 1. The default is that the local AHJ should conduct the inspection. However, if staffing does not permit or if the local jurisdiction does not have a qualified individual, the owner, occupant or operator can retain an AHJ approved NFPA 1031 qualified individual to conduct the inspection. Thereby, fire code compliance is achieved in accordance with the 1730 standard.

The frequencies of the fire prevention inspection are based on the occupancy risk classification.  Table 10.2.7.1 includes four classifications: high, moderate, low and critical infrastructure with frequencies ranging from annual to triennially or per the AHJ.  What is a high risk occupancy? What is critical infrastructure? The 2018 edition of the Code also added the corresponding definitions from NFPA 1730 to Chapter 3 to assist with the application of the new table.  For example, a low risk occupancy is “an occupancy that has a history of low frequency of fires and minimal potential for loss of life or economic loss.  Examples of low-risk occupancies are storage, mercantile, and business.

How does your jurisdiction manage fire prevention inspections for existing buildings?  Do you use the provisions in NFPA 1730?  What issues have you faced with existing building inspection?

Process of Commissioning & Servicing for Fire Blankets

Process of Commissioning & Servicing for Fire Blankets

A fire blanket is a safety device designed to extinguish small incipient (starting) fires. It consists of a sheet of fire retardant material which is placed over a fire in order to smother it.

Small fire blankets, for use in kitchens and around the home, are usually made of either fibreglass or woven-nylon coated with silicone-based flame retardant and folded in to a quick-release container for ease of storage.

Visual Inspection by the Responsible Person

1. The responsible person should carry out visual inspections of all fire blankets regularly. These visual inspections should be carried out at least monthly. When circumstances require, inspections should be carried out more frequently.
2. When carrying out these visual inspections, it should be ensured that:
3. each fire blanket is correctly located in the designated place;
4. each fire blanket is unobstructed and visible
5. the operating instructions of each fire blanket are clean and legible and face outwards;
6. each fire blanket container is not obviously damaged and that the hand hold devices are visible and undamaged
7. the tamper indicators of each fire blanket, where fitted, are not broken or missing.
8. The responsible person should record the results of these visual inspections and arrange for corrective action, where necessary, by a service provider. In the event of doubt the responsible person should arrange for a service provider to examine the fire blanket.

Mounting

Fire Blankets should be mounted so as to position the hand hold devices approximately 1.5 m from the floor.

The positioning of kitchen furniture and/or equipment should not preclude access to the blanket.

Process of Commissioning

The commissioning of a fire blanket should be carried out by a Person with the training and experience, with access to the relevant tools, equipment and information, manuals and knowledge of any special procedures recommended by the manufacturer of the fire blanket, to carry out the relevant maintenance procedures. Upon removal from its packaging and transit protection, and immediately prior to placing in its designated place, the fire blanket should undergo this sequence of commissioning service actions:

1	External examination of container	Examine the container for serious damage that could impair the safe operation of the fire blanket or the life of the blanket held inside.
2	Operating instructions	Check the operating instructions for correctness and legibility, ensuring that the text is in English.
3	Wall-mounting	1. Wall mount the fire blanket securely, ensuring that the hand hold devices are readily accessible, as designed.
		2. Most blankets require to be wall-mounted in the container to allow the blanket to be easily deployed when required.
4	Deployment	Check that the blanket is able to be easily released from the container as the manufacturer intended, by following the operating instructions.
5	Visual inspection	Check that the fire blanket has not been used; is not obviously damaged or has any hand hold devices missing or unsatisfactorily affixed to the blanket. Check the manufacturers label
6	Reassembly	Reassemble the fire blanket in accordance with the folding instructions of the blanket manufacturer. Replace with new any safety element designed to show whether the blanket has been deployed. Ensure the blanket is clean and dust free
7	Affix maintenance label	Affix the maintenance label to the blanket in an appropriate position on the container, and complete the details on the maintenance label.

Basic servicing

A)    The responsible person should ensure that basic service be carried out at 12 monthly intervals. The maintenance intervals given for basic service have for practical purposes a tolerance of ±1 month. Intervals should be taken from the date of installation or the last basic service. Intervals may be shortened, on the recommendation of the service provider where inspection reveals environmental and/or special hazards, or at the request of the responsible person.

B)    The basic service of a fire blanket should be carried out by a service provider. The fire blanket should undergo this sequence of commissioning service actions:

1	External examination of container	Examine the container for serious damage that could impair the safe operation of the fire blanket or the life of the blanket held inside.
2	Operating instructions	Check the operating instructions for correctness and legibility, ensuring that the text is in English.
3	Wall-mounting	1. Wall mount the fire blanket securely, ensuring that the hand hold devices are readily accessible, as designed.
		2. Most blankets require to be wall-mounted in the container to allow the blanket to be easily deployed when required.
4	Age	Check the age of the fire blanket.
5	Deployment	Check that the blanket is able to be easily released from the container as the manufacturer intended, by following the operating instructions.
6	Visual inspection	Check that the fire blanket has not been used; is not obviously damaged or has any hand hold devices missing or unsatisfactorily affixed to the blanket. Check the blanket is manufactured to BS EN 1869.
7	Reassembly	Reassemble the fire blanket in accordance with the folding instructions of the blanket manufacturer. Replace with new any safety element designed to show whether the blanket has been deployed.
8	Maintenance label	Complete the details on the maintenance label
9	Report	Write an inspection report advising the responsible person of the state of maintenance of the fire blanket

Labelling

General

Any labelling that is applied to the fire blanket container should not obscure any marking required by BS EN 1869.

Maintenance label

1. The maintenance record should be indelibly marked on a durable label that is fixed firmly to the fire blanket container without obscuring any of the manufacturer’s markings and instructions. Where there is no more space on the maintenance label and a new label is fixed, the date of commissioning should be marked on the new label.
2. The following information should be given on the maintenance label:
1. type of action (commissioning or basic service)
2. name and postal address of the maintenance supplier;
3. a mark clearly identifying the service provider;
4. the date (year and month) of the action in a) above;
5. the date (year and month) of commissioning

This information should be readable without any special equipment.

Any additional information for the benefit of service providers may be shown in a more compact form, such as bar codes.

Evaluation of fitness - Blankets which are to be condemned

Any fire blanket with a major defect or defects which make it unsafe for use should be immediately removed from its designated place, and marked “CONDEMNED” together with the reason for this assessment. The responsible person should be advised in the written report (Service Report) that a permanent replacement is needed as soon as possible. Evaluation of whether the damage or wear to a fire blanket make it unsafe for use depends on the judgement of the service provider.

Conditions indicating that a fire blanket is unsafe for use

Potentially the most serious hazard presented by a defective fire blanket is it’s inability to either (a) be deployed or (b) starve a fire of oxygen, allowing the fire to burn uncontrollably after deployment. These could be caused by any of the following conditions:

1. wear, contamination or damage to the fire blanket material.
2. wear or damage to the fire blanket hand hold devices;
3. serious damage to the container;
4. fire damage to the container or fire blanket;
5. age. Follow manufacturer’s instructions or if there are none then if more than 7 years from date of commissioning consider replacing the blanket.

Provision of a written report

The service provider should advise the responsible person in a written report or service report:

1. of any fire blankets that have been condemned or are missing;

2. of any permanent replacement fire blankets required to replace those reported in a);

3. of any additional fire blankets required to ensure that the level of cover at the premises is appropriate for the risks present;

4. that any replacement or additional fire blankets reported in b) or c) should be provided as soon as possible; and

5. of the responsible person’s obligation under fire legislation to provide an appropriate level of fire-fighting equipment at all times.

Permanent replacement of a Fire Blanket.

It is the duty of the responsible person to arrange for permanent replacement fire blankets to be put into place as soon as possible after inspection has shown that some fire blankets should be replaced. The service provider is responsible for bringing this duty to the responsible person’s attention in the written report.

Linear Heat Detection

Linear Heat Detection (LHD) is a versatile and economical fire detection product. Designed for use in a wide variety of fire and heat detection applications, LHD cable is particularly suited for harsh environmental conditions, where maintenance access is in a physical or hazardous area, and/or where there is a requirement to cost-effectively install fire detection in close proximity to the hazard. 

Linear Heat Detection cable is a combination of advanced polymer and digital technologies that can detect heat conditions anywhere along the length of the cable. The cable is comprised of two tri-metallic conductors individually insulated with a heat sensitive polymer outer-layer, and engineered to break down at specific fixed temperatures. This allows the twisted conductors to make contact and initiate a fire alarm condition at the control panel, without any calibration for changes in the ambient temperature. Nor is it required that a specific length be heated in order to initiate a fire alarm, adding to the versatility of this unique product. 

Alarm Point Location Setup

Each Protecto wire zone is field calibrated after installation to eliminate copper feed cable resistance from the Alarm Point Location reading. This is done by manually shorting the detector at the beginning of the zone and adjusting the display to zero "0000". 

Alarm Point Location Reading

When an overheat (alarm) occurs in a zone, an alarm point reading is taken either *manually or *automatically at the control panel. This reading represents the linear distance to the actuated point along the detectors length.

For further flexibility, Linear Heat Detection cable can be utilized with fire alarm control panels by utilizing either addressable monitor modules on an intelligent system, or by connecting the cable directly to the detection circuit of a conventional fire detection and control panel. In addition, the distance locating option allows the control panel to identify and display the exact location, in feet or meters from the fire panel, where the heat source interacted with the linear heat detection. That's a tremendous amount of valuable information in a small, easy to install and maintain fire detection package! 

·        Easy installation and maintenance

·        Minimal false alarms

·        Provides hazard coverage at every point on the cable for maximum protection

·        Compatible with intelligent and conventional detection and fire alarm panels

·        Available in a variety of lengths, cable coatings and alarm temperatures for maximum flexibility

Applications of LHS Cable

• Cable Trays
• Plant Rooms
• Vehicles
• Multi Storey Car Parks
• Thatched Roofs
• Industrial Kitchens
• Warehouses
• Waste Recycling Facilities
• Process Plants
• Hazardous Areas
• Power Stations
• Coal conveyors
• Cable Tunnels
• Access Tunnels
• Plant Rooms
• Shipping and Marine
• Engine Room
• Cable Ducts
• Ceiling Voids
• Kitchens