Element 7, Fire - hazards and control

Element covers:

• Basic fire principles, hazards and risks in the workplace
  
• Fire prevention and prevention of fire spread
  
• Fire detection, fire alarm and firefighting equipment
  
• Means of escape
  
• Evacuation of the workplace
  

Fire and fire safety which on any construction site is a major concern, The element describes the hazards which can cause fires, such as poor housekeeping, not enforced smoking policies, poor equipment maintenance, and the storage of flammable materials.

It is essential that a construction site has good housekeeping policies in place this effects most activities and can lead to becoming a fire risk if not enforced.

Smoking around flammable materials, and the storage of such couple with bad housekeeping can lead to quite serious fire risks. Flammable materials such as wood paper not just liquids should be stored in a safe and tidy manner, with the appropriate fire fighting equipment near to hand.

The storage of flammable liquids has separate legislation and if you are storing these in any significant quantity, you should look into this further.

Electrical fire are not categorised as a class of fire as others are (see table below) but electricity is a cause of many fires, therefore the correct use and maintenance of supplies and equipment are essential.

Class	Fuel/Heat source
Class A	Ordinary combustibles
Class B	Flammable liquids
Class C	Flammable gases
Class D	Combustible metals
Class E	Electrical equipment
Class F	Cooking oil or fat

Fire Fighting Mediums

Type	Old Code	BS EN 3 Colour Code	Fire Class
Water	Signal Red	Signal Red	A
Foam	Cream	Red with a Cream panel above the operating instructions	A	B			sometimes E
Dry Powder	French Blue	Red with a Blue panel above the operating instructions	A	B	sometimes C		E
Carbon Dioxide CO2	Black	Red with a Black panel above the operating instructions		B			E
Wet Chemical	No F Class	Red with a Canary Yellow panel above the operating instructions	A					F
Class D Powder	French Blue	Red with a Blue panel above the operating instructions				D

The element covers quite extensively the need for a site fire plan, correct and adequate signage.

A detailed fire risk assessment should be carried out and firstly any dangerous items or situations should be eliminated, after which strict control measure as previously described should be implemented along with adequate training for personnel. A culture which encourages operatives to report fires by firstly raising the alarm when a possible fire situation is observed without the risk of ridicule should be embraces.

Fire training into the correct procedures to follow in the event of a fire, fire drills, and responsible persons who can verify buy roll call that all people a present.

Records should be kept of fire induction training courses where personnel are informed of procedures, records should also be kept of the testing of equipment

In the event of a fire

• Raise the alarm
  
• Call the Fire Brigade
  
• Close all doors and windows to prevent the spread of fire (only if safe to do so)
  
• Leave the building
  
• Report to assembly point
  
• Roll call
  

If you are properly trained and only if should you

• fight the fire with the
  extinguishers provided but do
  not put yourself in danger
  
• keep between the fire and the
  way out, so that you can get
  out safely
  

When planning for work the fire risk assessment must be prepared alongside all other documents, thought should be given to the escape routes, any work place must have at least two exits, any controlled fires must be extinguished at the end of work, other hazardous equipment such as gas bottles should have the appropriate valves fitted and turned off when not in use.

Typical Examination Questions based on Element 6

1.	a) Describe the possible effects of electricity on the body. b) Outline FOUR factors that may affect the severity of injury from contact with electricity.	(4) (4)
	Affects such as interference with nerve/muscle action, tissue burns and cardio-respiratory effects, in particular the risk of fatal injury due to disruption of heart rhythm. As far as tissue burns are concerned, candidates should have identified as the main sites of damage the entry and exit points and warned of the possibility of damage to internal organs. Better responses included reference to secondary injuries such as head injuries caused by falls following electric shock. Factors such as the voltages involved the length of contact time, the route taken through the body, and the general health and age of the person involved. Additional factors that might affect the severity of the injury include the dryness of the skin, natural body resistance, ground conditions and the type of footwear being worn at the time.
2.	Outline the measures to be taken to minimize the risk of shock from the use of electric hand tools.	(8)
	Measures include: The use of reduced low voltage trough a transformer centre-tapped to earth The use of residual current devices or earth leakage protection. The protection and safe positioning of supply cables Using double-insulated equipment Using cordless (battery operated) equipment Ensuring the correct rating of fuses Introducing a system for routine visual inspection and testing of cables and equipment
3.	HSG65 Electricity at Work-Safe Working Practices gives guidance on the frequency of inspection for such equipment. State frequencies for the inspection and testing of electrical hand held tools and associate equipment used on a construction site and support your answers with appropriate examples.	(8)
	A hand held tool and equipment should be visually inspected before use, including cables, cord grips, casings and plugs. 230 volt equipment should be tested before first use and then at monthly intervals while a formal weekly inspection is also required. 110 volt equipment should be tested before first use and then at three monthly intervals while a formal monthly inspection is also required. Extension leads should have an initial test before first use followed and then at monthly intervals while a formal weekly inspection is also required
4.	List the items that should be included on an inspection checklist designed to ensure the safety of portable electrical hand-tools.	(8)
	Items on list could include: Equipment appropriate for the task and environment, equipment tested, plugs, connectors and cables free from damage or defect, correct wiring and sound connections, fuses and other means of preventing excess current in place and of correct rating, accessibility and appropriate means of isolation and system not overloaded.
5.	In relation to the use of electrical cables and plugs in the workplace: (i) Identify FOUR examples of faults and bad practice that could contribute to electrical accidents. (ii) Outline the corresponding precautions that should be taken for each of the examples identified in (i).	(4) (4)
	Examples include: Failure to select right equipment for the environment (armoured or heat resistant cables may be require). Incorrect rating of fuses. Ineffective or discontinuous earthing. Overload of Socket outlets. Cables unnecessarily long (or too short). The use of coiled extension leads. Poorly wired plugs (wires under tension or outer protective sheath not clamped). The use of defective cables and plugs. (ii) Precautions should have followed automatically from the deficiencies listed in (i)

Element 6 Electrical Hazards and Control

The section of the NCC1 describes what hazards are posed by the presence of electricity on a construction site, the hazards posed by the use of electricity and associated equipment such as hand tools, extension cables, portable and fixed lighting, temporary supplies from mains or generators.

The use of electrical hand tools is considered a major hazard on construction sites, therefore there are guidelines on the inspection and record keeping for these tools or equipment.

Testing

• Every installation should be tested in accordance with BS 7671: Requirements for Electrical Installation, before use on site, at three-monthly intervals or shorter periods if necessary.
  
• The record of any testing and inspections should be made by a responsible person on the appropriate certificates.
  
• Testing and inspections must include:
  
  • a visual inspection
    
  • the continuity of final circuit conductors
    
  • the continuity of protective conductors
    
  • the earth electrode resistance
    
  • the insulation resistance
    
  • polarity
    
  • the earth fault loop impedance
    
  • the correct operation of residual current devices and fault voltage operated protective devices.
    

Suggested inspection and test frequencies for electrical equipment on construction sites

Equipment/application	Voltage	User check	Formal visual	Combined inspection and check
Battery operated power tools and torches	Less than 25 volt	No	No	No
25V Portable hand lamps	25 volt secondary winding from transformer	No	No	No
50V portable hand lamps	Secondary winding centre tapped to earth (25 volt)	No	No	Yearly
110V portable and hand held tools, extension leads, site lighting, movable wiring systems and switchgear	Secondary winding centre tapped to earth (50 volt)	Weekly	Monthly	Before first use and then 3 monthly
230V portable and hand held tools, extension leads and portable floodlighting	230 volt mains supply through 30mA RCD	Daily/every shift	Weekly	Before first use and then monthly
230V equipment such as lifts, hoists and fixed floodlighting	230 volt supply fuses or MCBs	Weekly	Monthly	Before first use and then 3 monthly
RCDs fixed **		Daily/every shift	Weekly	* Before first use and then 3 monthly
Equipment in site offices	230 volt office equipment	Monthly	6 monthly	Before first use and then yearly
* Note: RCDs need a different range of tests to other portable equipment, and equipment designed to carry out appropriate tests on RCDs need to be used. ** It is recommended that portable RCDs are tested monthly

Key points

• Electricity can be a killer - you cannot see it and may not know that an item of equipment is live – until you touch it.
  
• Buried cables and those inside partition walls or other 'hidden places' are just waiting for the unwary to accidentally damage the cable and cause themselves serious injury or even death.
  
• The electrical distribution systems found on site tend to operate in a harsh environment and must be treated with care and respect.
  
• No-one other than a qualified electrician must alter the site distribution system.
  
• Ideally, apart from mains-powered equipment in site offices, all other equipment such as electrical hand tools will run off a 110 volt supply.
  
• The safest electrically powered tools and equipment are those that run off batteries.
  

Causes of electric shock

• Contact between a live conductor and earth.
  
• Contact between phase and neutral conductors (as the body is likely to have less electrical resistance than any load).
  
• According to the Health and Safety Executive, the majority of electrical accidents happen because people are working on or close to equipment which is either, assumed to be dead but is, in fact, live
  
• known to be live, but workers have not received adequate training, lack adequate equipment or have not taken adequate precautions
  

Legislation covering the use of electricity on construction sites

• The Management of Health and Safety at Work Regulations 1999 (as amended)
  
• The Construction (Design and Management) Regulations 2007
  
• The Electricity at Work Regulations 1989
  
• The Provision and Use of Work Equipment Regulations 1998 (as amended)
  

Working near overhead power lines

The local electricity company must be consulted before any work starts and a safe system of work must be devised and implemented. Other suppliers may also need to be consulted, for example, Local Authorities, National Grid and other electricity companies.

Special attention should be paid to traffic movements and the erection of appropriate warning sign and barrier (goalposts) should be erected, this apply to the use of excavating machinery near overhead power lines.

Typical Examination Questions based on Element 5:- Work equipment - hazards and control

1.	A leaking underground concrete reservoir has been emptied in order that it can be visually inspected prior to its subsequent repair. Describethe health risks faced by those repairing the reservoir when pneumatic tools are to be used to remove defective concrete and epoxy resin material used to effect repairs.	(10)
	Risks from excessive noise, the possibility of hand-arm vibration syndrome, and respiratory sensitisation and dermatitis from the use of epoxy materials, musculoskeletal problems due perhaps to the constraints of the working environment or the weight of the equipment. The repair task would also give rise to the possibility of respiratory problems associated with exposure to concrete dust
2.	Hand-held electric drills are commonly used on construction sites. Other than electricity. Outline FOUR hazards associated with the use of such equipment.	(8)
	Other hazards include entanglement with chuck or bit, stabbing or puncture by the drill bit, noise, vibration, dust and hazards associated with trailing cables.
3.	On a long-term contract, joiners are working with medium density fibreboard using hand-held circular saws and portable electric planers in a temporary site unit. Explainhow you would ensure that the joiner's health is not put at risk during this activity.	(8)
	Measures that include: assessment of the levels of dust, noise and vibration; the provision of efficient dust extraction equipment or respirators with the appropriate protection factor; the provision of hearing protection and the need to manage vibration by the use of lower vibration tools or job rotation.
4.	(a) Describe when a fixed guard would be an appropriate means of providing protection against mechanical hazards. (b) Outline the features of fixed guards designed to minimise the risk of injury or ill health from dangerous parts of machinery	(2) .(6)
	(a) Appropriate when providing protection against mechanical hazards when infrequent or no access is required to dangerous parts of a machine during its normal operation. (b) Factors such as; the material of construction, which should be sufficiently robust and be able to contain any ejected material, but still allow sight of the process when required; the method of fixing, usually requiring the use of a special tool for the guards removal; the need to ensure that any necessary openings in guards are such that they do not allow access to the dangerous parts and the need to address the possibility of the guard reverberating and exacerbating a noise problem

Manual Handling Quiz

from www.healthandsafetytips.co.uk

1.	When is a manual handling risk assessment required?
	Before the task is carried out and no other option is available
2.	What are the FOUR Elements of a Manual Handling Risk Assessment?
	T…………….Task I……………..Individual L…………….Load E…………….Environment
3.	What should you do when confronted by a large or awkward load that has to be manually handled?
	Stop and assess whether there is an alternative method Assess the load to see if it can be handled safely, Ask for assistance
4.	Name 2 of an EMPLOYER'S Duties?
	Tasks should be assessed with a view to using alternative methods where possible Ensure personnel requested to complete the task have had adequate training and capable of completing the task without injury
5.	Name 2 of an EMPLOYEE'S Duties?
	To ensure that the correct methods of manual handling techniques are adopted
6.	Name 2 parts of the body you may injure during Manual Handling Activities
	Spine , Abdomen / groin
7.	List 3 Key points of KINETIC lifting
	The load should be lifted whilst keeping the back straight , feet correctly placed, and perform a clean lift without twisting
	Manual Handling Questions Model Answers
1.	When it is not reasonably practical to avoid an activity that may result in injury to the employee. When it is not reasonably practical to use mechanical means for the operation.
2.	Task, Individual, Load, Environment.
3.	Seek Assistance and Use team Lifting Methods.
4.	Safe Appliances and Equipment Safe Handling of Materials Information, Instruction and Training A SAFE Place of Work and Safe Working Equipment A Safe Means of Access and Egress A Suitable and Sufficient Risk Assessment for all Work Activities
5.	Take reasonable care of their own safety and that of others. Co-operate with their employer to enable him to meet their legal obligations. Bring to the attention of the employer any concerns regarding health and safety standards. To use equipment provided for your health and safety.
6.	Back, Hands, Knees, Arms, Legs.
7.	Position and Plant Feet, Bend Knees, Straight Back, Arms Close to Body, Good Grip of the Load, Chin In, Head Up, No jerking or twisting, clean lift.