Asbestos- NEBOSH Quick Revision Sheet

Asbestos- NEBOSH Quick Revision Sheet

Asbestos- NEBOSH Quick Revision Sheet

Reason Why Asbestos is so Dangerous
  • Asbestos fibres are tiny needle-like in shape.
  • It is not the chemical composition of the fibres but their shape/size that cause health problems.
  • Fibres most likely to damage health can be less than one thousandth of a millimetre in diameter.
  • All asbestos is dangerous to health, but blue and brown are the most hazardous and have been banned in the UK for many years (since 1984).
  • However, white asbestos was only banned in the UK in 1999.

Types of Asbestos / Asbestos Related Diseases
Chrysotile
(white) / /
  • Asbestosis
–Fibres lodge in lungs & cause inflammation that heals leaving scars and lungs losing ability to deliver oxygen to the blood.
  • Mesothelioma
–Cancer of the lining of the lung, the lining of the abdomen or of the heart – can take 20-50 years to develop.
  • Lung cancer
–Exposure to asbestos increases the risk of lung cancer.
  • Diffuse Pleural Thickening
–Some asbestos fibres inhaled into the lungs may work their way to the pleura causing it to thicken leading to breathing difficulties.
  • Pleural Plaques
–This is the least serious form of asbestos induced disease. ‘Plaques’ are scars in the lining of the lung.
Grunerite
(brown)
aka Amosite /
Crocidolite
(blue) /
Notes …
The pictures above show the asbestos in its raw form, but this is not how you would usually find it in the workplace or building as it is usually used to bind together another product.
The HSE produce a document called Asbestos Surveying Techniques (HSG264), which is an excellent document for indicating all the places where asbestos was known to be used in the past along with the types and typically concentrations.
  • The properties that made it so attractive were:
  • It was extremely strong and mixing it with other materials, gave those materials strength;
  • It was excellent for soundproofing;
  • It was an excellent insulator for heat;
  • It was excellent as a shield against heat;
  • It was resistant to chemical attack.

Duty of Owners of Non-Domestic Premises to Manage Asbestos
  • Controllers of non-domestic premises should:
–Locate asbestos by undertaking surveys (Management or Renovation/Demolition.
–Make a writer record of the location of any asbestos, known or suspected in an Asbestos Containing Materials (ACM) Register
  • Management Survey Stage 1:
  • Location & assessment survey or Presumptive survey
  • To locate the presence & extent of ACMs and assess their condition
  • Defers the need for sampling & analysis
  • A surveyor should have strong evidence to support a reasoned argument for presuming a material does not contain asbestos
  • Management Survey Stage 2:
  • Standard Sampling & Assessment survey
  • Same as type 1 except that samples are taken from each type of suspect ACM and analysed
  • An assessment is made of all materials confirmed to contain asbestos
  • UKAS accreditation to ISO17025 for analysis
  • Renovation (major refurbishment) or Demolition Survey:
  • Full access sampling and identification
  • Undertaken by a HSE licensed contractor
  • Sent to UKAS accreditation to ISO17025 for analysis
–Given its location and current condition, assess risks of potential exposure in the case of it being disturbed or damaged during day-to-day and maintenance works.
–Develop management plan to control the potential exposure
–Implement the plan; and
–Monitor and review (usually annually)
Unlicensed Work with Asbestos / Licensed Work with Asbestos
  • Air monitoring
–WEL of 0.1 fibres per cubic centimetre of air (f/cm3) averaged over 4 hours
–Above this limit, an asbestos licence will be required
  • Unlicensed work – 2 cats
–Notifiable (friable ASB NLWN 1 on-line). Workers involved in unlicensed notifiable work require to be enrolled in health surveillance
–Non-notifiable (not friability)
  • Friable means tendency to crumble e.g. in poor condition.
  • HSE website has a range of risk assessments and safe systems of work for these types of activities.
/
  • Licensed contractor has to notify HSE on an ASB5 form 14 days before start of work
  • Operative health surveillance
  • Outer area of work to be barriered of and signed to keep unauthorized people out.
  • Actual area of work to have a double enclosure with a Local Exhaust Ventilation system installed in the inner area to produce a negative pressure system so no dust escapes (usually tested with a smoke tube.
  • The will bring their own 3 stage (dirty/ shower/clean) decontamination facilities:
–Will remove all personal clothing
–Will wear total coverage PPE/RPE
–Even sludge from showers collected
  • Waste is double bagged, 1st bag applied in the inner asbestos removal area and 2nd bag applied in the outer area (both sealed and labeled) and place in a skip (usually lockable)to be removed by licensed hazardous waste carrier. Consignment Notes should be obtained from the carrier and kept for a minimum of 3 years.
  • Disposal is achieved by putting waste into the lower cells of a fairly new land fill site, these are very limited.

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