Working at Height- Fall Hazards and Risk Control Measures

Falls from height are the most common cause of fatal injury and the second most cause of common cause of major injuries to employees. Working at height may include work on roof, using ladders or any access platform such as scaffolds or lifting equipment.

The main hazards from Working at Height are Falls i.e, Persons falling and falling equipments.

The main causes of falls from height are:

• Failing to recognize the risk.
• Not providing safe system of work and making sure its followed.
• Not providing adequate information, training, instruction or supervision.
• Not using equipment properly or sometimes not using it a all (using chair instead of step ladder).

Unsafe act may lead to a Fall

When Fall protection is needed?

During roof work, fall protection is always required when the roof edge is more than 10 feet above the ground or other surfaces. This commonly referred to as, 10 foot rule.

But when any roof is so steep or slippery that an uncontrolled fall would likely happen, fall protection is required at 6 feet.

Types of Fall Protection

Fall protection can be divided into following two categories:

Fall Restraint- equipment that prevents a free fall in the first place.

Fall Arrest- equipment that stops a free fall in progress (in the middle of the fall).

Fall Restraint

Fall restraint system includes three main types;

Fall Prevention system

1) Personal fall restraint 

Fall restraint can be a Body Belt or Full Body Harness, which is, connected to an anchor to prevent you from going over the edge of the roof. No matter where you work on the roof.

2) Guardrails

These are most practical on flat or low pitched roofs.  

Guardrails must be 39-45 inches high and have a Top rail, mid-rail and toe-board.

Must be able to withstand 200 pounds of force in any direction.

Roof openings are also fall hazard and must be covered or surrounded by a guardrail.

Safety Monitor and Warning-line

3) Warning line and Safety Monitor System

The warning line is installed at 6 feet from roof edge at height of 36-42 inches.

Line is flagged every six feet.

Equipment cannot be stored outside a safe area.

When working outside the safe area or warning line you must wear fall protection or have a safety monitor when working outside the warning line.

You must wear a high visibility garment outside the line and take it off when inside the line.

As for Safety Monitor, his only job is to watch and warn workers of fall danger. Can monitor up to eight workers. There should be clear view between him and workers.

Fall Arrest

Two main types of fall arrest that are used during roofing are;

1)  Personal Fall Arrest- Full body Harness, Body Belt.

2) Catch Platform- sometimes used on large buildings,
Other measures include Safety net and Debris net.

Catch Platform

• Must be no lower than 10 feet from roof edge.
• Must be at least as wide as fall distance but never less than 45 inches in width.
• Must have Guardrails, toe-board and not used for storage of materials.
• Catch platform must conform with scaffold standard.

Personal Fall Arrest

• A full body harness is a common fall arrest system used in roofing.
• A full body harness stops a fall in progress and minimizes the force of fall to your body.
• Waist belts are not allowed because a fall will usually result in injury. Since high force of fall is concentrated at your waist rather than 6 points of full body harness
• The attachment point on a full body harness is D-ring on your upper back.
• It must be an ANSI Class III harness. Recreational climbing harness are not allowed.
• Be sure to use a size that fits you properly.
• Some fall arrest gear comes with shock absorbing lanyard, must be adjusted to prevent hitting to the ground or lower level. Because in a fall, the equipment stretches several feet.

Anchors

Fall arrest gear is only as good as the anchor. An anchor must be able to withstand 5000 lbs of force without failing.Manufactured anchors must be installed according to manufacturer's instructions.
Check pre-installed anchors before using, in fall your life depends anchor holding.

A knot can be used to secure a lifeline to an anchor point only when, you know the breaking strength of the life line and the knot doesn't decrease the strength of the lifeline to below 5000 lbs.

Equipment Do's and Don'ts -Fall Arrest Gear

• Do inspect for wear and damage before use.
• Do remove from service after fall for inspection.
• Dont use to life materials
• Dont attach to a guardrail or hoists.
• Look for the following:
• Webbing, D-rings, Tongue buckle and Ropes for any sign of damage, wear cuts, tears corrosion , cracks etc.

Precaution Measures for Working at Height
If the work you're responsible for includes working at height, you need to make sure that:

• Its properly planned and organised.
• The workers are competent
• You've assessed the risk from working at height, chosen appropriate work equipment and made sure that the staff uses it.
• You've controlled the risk from fragile surfaces.
• Equipment for working at height is properly inspected and maintained.

Avoid working at height wherever possible, if you cant avoid it:
Use work equipment or other measures to prevent falls.
Use work equipment or other measures to minimise the distance and consequences of f fall.

Note:

Extended above edge-ladder

Ladders are fall hazard too. It should be resting on a stable and level base and should be extending 3 feet above the edge. Standard for ladder erection is 4:1 (for 4m height 1m distance from wall).
The person using ladder should not carrying anything and hands should be free. Three-point contact (two hands and a foot, or two feet and a hand) shall be maintained with ladder while climbing.

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Electricity Hazards and Controls

Electricity is an integral part of our life and modern day cannot be imagined without it. But with all the benefit it brings in our life it has it also carries certain hazards which we are going to look at.

How the Electricity Works?

For electricity to work we need a source and a conductor. The source can be a power generator and wires can be conductors which can carry current.

What are Electrical Hazards?

Electrical Hazards can be as:

>Electric Shock

Electric Shock-contact with live conductor

Main type of harm from electricity is electric shock. An electric shock occurs when a person comes into contact with an electrical energy source. The electrical energy flows through a portion of the body causing a shock  (you become part of the circuit).

The effects of electric shock may include Heart failure, respiratory failure and burns.
Also, The passage of electric current through body causes muscles to contract violently. As a result you can become unbalanced and Fall off a ladder or hitting against some object on same level.

Severity of electric shock depends upon:

• The nature (AC or DC) and amount of current passing through the body.
• Path taken by the current through the body.
• Length of time body is in the circuit.
• Resistance of body to electric flow (young, old, wet)

>Arc Flash or Arc Blast

An arc flash (also called a flashover) is, part of an arc fault, a type of electrical explosion or discharge that results from a low-impedance connection through air to ground or another voltage phase in an electrical system.

Deadly Arc Flash while working with electricity

When an arc fault occurs, the result is a massive electrical explosion. The light and heat emitted by the explosion is known as the Arc Flash, and the pressure wave is known as the Arc Blast. An arc flash releases hot gases and concentrated radiant energy up to four times the temperature of the sun’s surface, which can melt metal and cause severe radiation .
It can cause severe burns, damage to eyesight, and even result in fatalities. And even if an arc blast doesn’t injure a person, it will damage equipment and cause downtime.

Electricity can also cause;

>Electrical Burns 
Typically occurs on hands when you touch electrical wiring or equipment that is improperly used or maintained.

>Fires
Fires of electric origin may be cause by overloading hazards. If too many devices are plugged into a circuit the current will heat the wire to a very high temperature which may cause a fire.
Or, If a wire insulation melts arcing may occur and cause a fire in the area where the overload exists even inside a wall.

Causes of Electrical Hazards:

Most electrical mishaps are caused by a combination of three factors:

1) Unsafe Work practices.

2) Unsafe equipment or installation.

3) Workplaces made unsafe by the environment.

Most deaths and injuries from electricity are due to:

• Using poorly maintained electrical equipment
• Working near overhead power lines
• Contact with underground power cables during excavation work
• Working near domestic electricity supplies
• Use of unsuitable electrical equipment in explosive atmospheres.

Preventing Electrical Hazards

Electrical hazards can be prevented through proper:
- Insulation
- Grounding
- Using of electrically protective devices.
- Safe work practices.

What to do if electrocution occurs?

In dealing with electricity never exceed your expertise

• Call for help.
• Do not touch the victim or the conductor.
• Shutoff the current at the control box.
• If shutoff is not immediately available, use a non-conducting material to free the victim.
• If necessary, begin CPR (Cardio Pulmonary Resuscitation ).

7 out of 10 victims revived when artificial respiration was given. But after three minutes the chances of revival decreases. 

Note:

To prevent contact with energized overhead power lines (cause of 45% of accidents in crane works)
> De-energize overhead lines
> Maintain minimum distance i.e,

• 10 feet distance for 50kv
• If over 50kv, add 4 inches per 10kv 

> Use proximity alarms
> Use of warning signs around source of high electric power.

Watch this video for safe escape from electrocution:
https://www.youtube.com/watch?v=AkwyxVEIDDM


For further details on electrical safety check;
NFPA 70E: Standard fr Electrical Safety in Workplace


Hope you've found this article informative and interesting. Keep tuned for more.

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Fire Hydrant system

A fire hydrant, (also known as fire pumps, hydrant boosters, fire water pumps)is a connection point by which firefighters can tap into a water supply.
These are high pressure water pumps designed to increase the fire fighting capacity of a building by boosting the pressure in the hydrant service when mains is not enough, or when tank fed.

A Fire Hydrant with fully-on valve , releasing pressure water.

Safe Operating Procedure- Fire Hydrant

The user attaches a hose to the fire hydrant, then opens a valve on the hydrant to provide a powerful flow of water.  Most fire hydrant valves are not designed to throttle the water flow; they are designed to be operated either full-on or full-off.

Attaching Hose with Fire Hydrant

When a firefighter is operating a hydrant, he or she typically wears appropriate personal protective equipment, such as gloves and a helmet with face shield worn. High-pressure water coursing through
a potentially aging and corroding hydrant could cause a failure, injuring the firefighter operating the hydrant or bystanders. In most jurisdictions it is illegal to park a car within a certain distance of a fire hydrant. In North America the distances are commonly 3 to 5 m or 10 to 15 ft, often indicated by yellow or red paint on the curb. The reason behind these laws is that hydrants need to be visible and accessible in an emergency.

Hydrant Color Coding 

Hydrant-Green color

Hydrant coloring may be due to either purely practical criteria or more artistic. In the United States, the AWWA and NFPA(National Fire Protection Assocation) recommend hydrants be colored chrome yellow for rapid identification apart from the bonnet and nozzle caps which should be coded according to their available flow. Class AA hydrants (>1500 gpm) should have their nozzle caps and bonnet colored light blue, Class A hydrants (1000–1499 gpm) green, Class B hydrants (500–999 gpm) orange, Class C hydrants (0–499 gpm) red and inoperable or end-of-system (risking water hammer) black. This aids arriving firefighters in determining how much water is available and whether to call for additional resources, or find another hydrant

Inspection and Maintenance:

In most areas fire hydrants require annual inspections and maintenance — they normally only have a one-year warranty, but some have 5- or even 10-year warranties, although the longer warranty does not remove the need for periodic inspections or maintenance. Some fire hydrant manufacturers recommend lubricating the head mechanism and restoring the head gaskets and O-rings annually in order that the fire hydrant perform the service expected of them, while others have incorporated proprietary features to provide long-term lubrication of the hydrant's operating mechanism. In any case, periodic inspection of lubricants is recommended. Lubrication is generally done with a food-grade non-petroleum lubricant to avoid contamination of the distribution system.
Watch this short video for correct inspection and use of hydrant system:
https://www.youtube.com/watch?v=HTIBkvDy3vk

Dry Hydrant 

Dry hydrant pipe

In rural areas where municipal water systems are not available, dry hydrants are used to supply water for fighting fires. A dry hydrant is analogous to a standpipe. A dry hydrant is usually an unpressurized, permanently installed pipe that has one end below the water level of a lake or pond.The other end is above ground. When needed, a pumper fire engine will pump from the lake or pond by drafting water. This is done by vacuuming the air out of the dry hydrant.

Standpipes

Standpipes are connections for firehoses within a building and serve the same purpose as fire hydrants in larger structures. Standpipes may be "dry" or "wet" (permanently filled with water).

Stand Pipe-Vertical

Note:

- GPM means Gallon Per Minute.
- For Water-Based Fire Protection Systems, check NFPA Code- 13, 14 and 291.

Following are some NFPA-1 standards related to fire hydrant:

• 18.5.7 Clear Space Around Hydrants.
• 18.5.7.1 A 36 in. (914 mm) clear space shall be maintained around the circumference of fire hydrants except as otherwise required or approved. 
• 18.5.7.2 A clear space of not less than 60 in. (1524 mm) shall be provided in front of each hydrant connection having a diameter greater than 21⁄2 in. (64 mm).

NFPA-24

• 6.2.10 All control valves shall be located where readily accessible and free of obstructions.

Hope you've fund this articles very informative. 

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Fire Extinguisher- All you need to know

Fire extinguisher is an active fire protection device used to extinguish or control small fires, often used in emergency situation.

A fire extinguisher can help save lives and property by putting out small fires or containing it until fire fighters arrive.

(Parts of Fire extinguisher)

Types of fire extinguishers

There are four basic types:

1) APW (Air Pressure Water)

2) DCP (Dry Chemical Powder)

3) CO2 (Carbon dioxide)

4) Foam based.

When choosing Fire extinguisher it is necessary to select the correct fire extinguisher based on Class of fire. 

Following is a Fire extinguisher Chart showing the right type of fire extinguisher for type of fire.

Never use Water or Foam based fire extinguisher's on fires of electric origin or on live electrical equipment. Because it can conduct electricity and may cause electrocution.

Based on mode of transportation, it can be either Handheld extinguisher or Cart-mounted

extinguisher.

How to use fire Extinguisher?

As for the person intending to use the fire extinguisher he should know:

>How to use the extinguisher quickly without taking time to read the directions during an emergency situation.

>Be strong enough to lift and operate it.

>Keep in mind that your extinguisher must fit the type of fire.

>In order to use extinguisher keep in mind- P.A.S.S (Pull, Aim, Squeeze, Sweep).

Keep in mind that portable extinguishers are not designed for fighting large or spreading fires. Also, one must not endanger his life by fighting fire with wrong, insufficient equipment.

Out of reach Extinguisher.

Fire Extinguisher-Placement:

•  30 meters apart from one place to another

•  Minimum two locations on any floor

•  Readily visible on escape routes

•  Away from any source of fire

•  Properly mounted and within reach or easily accessible.

When you need to Replace a Fire Extinguisher!

Do Fire Extinguisher expire? This is a question that we get all the time. Well, Fire extinguishers of any kind don't typically expire. They may occasionally need recharging especially after you discharge them. According to manufacturers, most extinguisher should work for 5 to 15 years. But you may not know that you got yours 3 years ago or 13. So how can you be sure it will work?

(Pressure gauge- Needle in green zone)

Well, Its recommended to inspect the pressure gauge once a month-by yourself and annually by a professional fire extinguisher inspection company who will place month and year inspection tags on the extinguisher. Most important thing to do is to make sure that the needle in the pressure gauge is in the green zone- this means its functional. If it falls anywhere else, the extinguisher is unreliable and should be serviced or replaced. For older model without gauge, have it checked by any professional. 

When do we need to Replace it?

Replace or service Fire Extinguisher right away if it's been used or if you notice any of the following:

• The Hose or nozzle is cracked, ripped or blocked with debris.
• The safety pin on handle is missing or seal is broken.
• The handle is broken or wobbly.
• The inspection sticker or hang tag, with record of checkups and maintenance, is missing. 

 Is it better to Replace or Recharge a Fire Extinguisher?

It depends. If your Extinguisher is still fairly new (less than 5 years old), recharging may be an option. However, the Extinguisher's replacement is just as good! Because it typically costs about the same as recharging and will guarantee the extinguisher works perfectly.

Note:
In addition to having your extinguisher inspected annually, should should have it hydro-tested every 12 years. A Fire Extinguisher hydro-test is the best way to check for any cracks or degradation of the Fire extinguisher shell and will help you you to tell weather your old Fire extinguishers are upto the task.

For details on Standards check following:
- NFPA 10: Standard for Portable Fire Extinguishers.

- OSHA  Standard Number: 1910.157, Title: Portable Fire Extinguishers :

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9811


Also check these Inspection videos: 
https://www.youtube.com/watch?v=P3c7CFF0rDs
https://www.youtube.com/watch?v=6YTE5ewqO28

Hope you've found this article helpful.  Keep visiting for more topics.

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Fire detection and firefighting equipment

All workplaces must have arrangements for:

i)  Fire Detection and alarm system
ii)  Fire Fighting equipment

i) Fire Detection and alarm systems

This includes use of manual and automatic systems.

Manual alarm systems are suitable for small workplaces and involve the use of following basic devices:

(Manually operated electric alarm device)

• Rotary gong- operated by turning the handle.
• Hand strikers- suspended iron triangles which are struck by metal bars manually.
• Hand bells.
• Whistles.
• Air-horns.

The call point in manually operated electrical system are usually small red wall mounted boxes which are designed to operate either automatically when the glass front is broken.

As for automatic fire detectors and alarm systems, following are three main types:

1) Smoke detector

By sensing presence of smoke or other fumes (often invisible given off by combustion).

2) Radiation detector

By detecting presence of flame and degree of illumination.

3) Heat detector

By sensing heat or the rate of rise in temperature- Fusion, Expansion.

Factors for selection of type of detector:

-The conditions in the area to be protected- Dusty or damp atmospheres will affect some detector more than others.

-The sensitivity required- it would not be sensible to install a smoke detector set at high sensitivity in a normally crowded hotel bar or similar conditions.

-The availability of suitable locations- should be located in the best possible position to perform their function.

-The potential for false alarm- false alarm can happen for many reasons and are often unavoidable.

ii) Fire Fighting Equipment

Fire fighting equipment includes:

• Fire extinguishers- which is portable fire protection device used to extinguish or control small fires often in an emergency situation.

Other fire fighting equipment include:

Automatic Sprinkler system in action.

• Fire hydrants
• Fire Blanket
• Hose Reels
• Foam inlets 
• Drenchers.
• Automatic-Sprinklers. 

Hope you've found this topic informative. Stay tuned for further topics and details.

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What to do in the event of fire at workplace?

There should be a comprehensive fire action plan and regular fire drills for dealing with such situation in your organisation. Here's what need to do in event of fire:

Raise the alarm 
A person discovering fire should raise alarm manually if possible. The alarm can be electric or manually operated system such as bells or rotary gong etc. Fire alarm usually operates automatically by breaking the glass in front of fire alarm switch. Alarm should be clearly audible throughout the building.

Alert the staff and summon fire brigade
Need to alert the the staff so that the persons who are required to assist in situation resume their roles and ensure evacuation of people especially those who need assistance. While summon the fire brigade and direct emergency services.

Fight the fire and prevent it from spreading
Fight the fire using fire fighting equipment such as fire hose, Fire extinguishers, fire blankets. but one must not endanger himself while trying to fight the large or spreading fire.

Evacuate the building
Ensure that everyone has left the building or is leaving. An up-to scale, single line drawing of premises should be present. Their should be adequate emergency escape routes with fire doors. It should be well lit and free of any obstruction and clear directional signs showing where to go. Everyone need to be evacuated by help of fire warden or fire marshals and be collected at assembly point or muster point where roll calls would be carried out to ensure complete evacuation.

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Fire Risk Assessment

Steps of fire risk assessment

Following are the steps of fire risk assessment;

Step 1- Identifying the hazards

Knowledge of fire triangle can assist to identify the hazards for potential fire situation i.e,

Identify any source of ignition- such as flames or sparks from welding, cutting, grinding or use of hot air gun. 

Any Combustible fuels- such as paper, wood, cardboard, petrol, kerosin oil, thinner, methane gas etc.

Also, any unsafe procedures or acts- persons taking unsafe acts such as smoking next to combustible materials.

Any unsafe conditions-  These are the conditions that may assist the fire to spread in your work place. Such as bad Housekeeping, it is responsible for many small fires either starting or certainly spreading involving far more of the premises that was necessary. 

Step 2- Decide who could be harmed

Identify any staff or persons who are specially at risk and need to consider matters carefully if:

• Sleeping accommodation is provided 
• Persons are challenged e.g, physically, visually, mentally etc.
• People are unable to react quickly- children, old.
• A simple single line drawing of premises to scale can be helpful.

Step 3- Evaluate the risk-existing controls are adequate?

Having identification of hazards, need to reduce the chances of a fire by,

• Removing hazards all together (Eliminate)
• Reducing the hazard to the point where there is little to no risk or
• Replacing the existing hazard with safer alternative (Substitute)
• Segregating the hazard from workplace (Engineering controls)
• Developing a fire safety policy and culture to ensure that fire hazard do not occur in workplace (Administrative controls).

Also evaluate, means of escape & emergency lightning are they adequate in size, number, location, well lit, unobstructed, safe to use.
- Fire fighting equipment-wall mounted fire extinguishers, suitable for type of fire and in sufficient numbers.
- Means for detecting and warning in case of fire, can it be heard by all occupants/employees.
- Training of employees- what to do in the event of fire.
- Alongside Classify the areas: Low risk, Normal risk, High risk.

Step 4- Record the findings and actions
Finding of assessment and actions should be recorded and must have to retain a recored of significant finding if having more than 5 employees, and should indicate:

• Date the assessment was made
• The hazards identified
• Any staff or other people at risk
• What action need to be taken and when
• The conclusion arising from the assessment

Step 5- Review, revise and monitor

Fire risk assessment is not a one off procedure and should be continually monitored to ensure that existing fie safety arrangements and risk assessment remain realistic.

The assessment should be revived if there is a significant change in the work activity, in the materials used or stored or when any building works are proposed.

(Click image for Fire Checklist)

For Generic or specific fire risk assessment template visit following link:
https://www.shropshirefire.gov.uk/safety-at-work/generic-fire-risk-assessment-template

Hope you've find this article very informative and useful. Keep in touch for further topics and issues.

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Heat Transmission and Fire spread

There are four ways in which heat can be transmitted:

1. Conduction
This involves transfer of heat without transfer of molecules (usually solid).

2. Convection
Convection is a process whereby  heat moves through a gas or liquid and involves actual movement of molecules.

Process showing conduction convection and radiation.

3. Radiation
Radiation is the mode of transfer of heat (as invisible waves through the air) from source, without any media. For example infrared, microwaves in microwave ovens.

4. Direct burning
Combustible material in contact with naked flame.

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