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NEBOSH DIPLOMA UNIT B > B3 HAZARDOUS SUBSTANCES ENGINEERING CONTROL & PPE > Flashcards

B3 HAZARDOUS SUBSTANCES ENGINEERING CONTROL & PPE Flashcards

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1
Q

What does LEV stand for

A

LEV stands for Local Exhaust Ventilation

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2
Q

What does an LEV system do

A

What does an LEV system do?

It takes contaminants (dusts, mists, gases, vapour or fumes) out of the air so that the cant be breathed in.

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3
Q

What are the three key points of an LEV

A

Three key points are:

1) takes contaminated air away from a specific contaminated source
2) minimises the air entering the operator breathing zone
3) clean the air (if necessary) and gets ris of the contaminants safely

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4
Q

When might an LEV not be the right control system?

A

An LEV might not be the right control system when

1) there are a large number of widely-spaced sources
2) the source if large and LEV is impossible to apply over the entire source
3) the source position is not fixed
4) the source emitted relatively small amounts of contaminant (which is not toxic)
5) the contaminant is offensive but not harmful (smells but no harm)

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5
Q

For and LEV what do you need to consider?

What do you need to consider when selecting an LEV?

A

For and LEV you need to consider

  • Particle size - are they inhalable or respirable
  • Viability of particle clouds - respirable dust clouds are practically invisible - inhalable dust clouds are partially viable, mist and fume are more visible the dust
  • Movement of particles in the air, small particles float and large particles travel a small distance before settling quickly (LEV need to remove both suspended inhalable particles and intercept the larger particles…think woodwork dust and chips)
  • Abrasive or corrosive particles, some particles are more abrasive than others SILICA and some more chemically active ACID. Needs to be taken into consideration of material used to construct the LEV
  • Sticky dust, mist and condensate. heavy condensate can block ducts (drain points, access points for cleaning)
  • Flammable or combustible substances. many organic and dust metals (zinc) are combustible and LEV systems need to reduce the chances of ignition and cope with a possible dust explosion.
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6
Q

Name the components of an LEV system

A

The basic components of an LEV are:
HOOD/INLET - to collect contaminant at source
DUCTWORK - to take it away from the source
FILTER/AIR CLEANER-to remove containment from the extracted air stream
FAN -to provide the airflow
EXHAUST/OUTLET -discharges the cleaned air to the outside somewhere safe

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7
Q

What are the different types of enclosure

A

Three different types of enclose

1) full enclosure - glove box
2) room enclosure - operator and process enclosed (paint spraying a room)
3) partial enclosure - fume cupboard

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8
Q

Name 4 types of hood extractor

A

ENCLOSING - effective as all the work done in the hood
RECEIVING - speed and direction good for hot works, think about grinder
CAPTURING - common, generates airflow at the source to capture and draw in the air
RECEPTOR - like you get over a furnace the hood covers all the work to avoid fugitive emissions

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9
Q

How do you know how effective and LEV is

A

The effectiveness of and LEV can be judged by

  • -how much the hood constrains the contaminant cloud
  • -how well the LEV induced airflow carries the contaminant cloud into the system
  • -how little of the contaminant cloud enters the process operator breathing zone.
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10
Q

What are the design considerations for ductwork

A

The design considerations for ductwork should be:

  • -keep the design simple
  • -use a suitable material resistant to the contaminant
  • -have high air velocity to keep particles suspended
  • -minimise noise
  • -keep the pressure negative
    • minimize the number of bends and junctions
  • -smooth bends
  • -no T junctions
  • -used tapered sections
  • -provide drainage points at any low points
  • -provide access points for cleaning and blockage removal
  • -accommodate thermal expansion and contraction
  • -be able to withstand wear and tear
  • -avoid settled particles by making sure the velocity is high enough (think woodworking dust…sticky….can narrow the duct and block it)
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11
Q

What is the minimum duct velocity for gases and non condensing vapours (face or dust)

A

What is the minimum duct velocity for gases and non condensing vapours (face or dust)

velocity of 5 m/s

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12
Q

What is the minimum duct velocity for condensing vapours, fume and smoke

A

What is the minimum duct velocity for condensing vapours, fume and smoke

velocity of 10 m/s

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13
Q

What is the minimum duct velocity for process dust (cement dust, brick dust, wood shavings, grinding dust)

A

What is the minimum duct velocity for process dust (cement dust, brick dust, wood shavings, grinding dust)

velocity of 20 m/s

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14
Q

Name four PARTICLE COLLECTORS

A

Four particle collectors are:
FABRIC FILTER - for dry dusts. 99.9% efficient for 5um particles. Filters need replacing and cleaning (mechanical shaking, reverse airflow, pulsejet)
CYCLONES - throws particles out to the wall by centrifugal which drop to collection hopper. 40-70% efficient for 5um particles. Cheap as no filter
ELECTROSTATIC PRECIPITORS - less air resistance than fabric- 92% efficient for 5um particles. dust particles are charged and attracted to plates of opposite charge but not all particles can be charges. not suitable for heavy contamination. pipe or tube or parallel plate
SCRUBBERS - wetting particles and washing them out of a contaminant cloud. 96% efficient for a 5um particle. more efficient than a cyclone. used in large gas plants. two types VENTURI SCRUBBER (common), SELF INDUCED PRAY COLLECTOR, WET CYCLONE SCRUBBER, PACKED TOWER SCRUBBER

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15
Q

When selecting a filter what do you need to think about

A

When selecting a filter what do you need to think about?

is the contaminant a solid, liquid or gas as the filter needs to be appropriate

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16
Q

What are the two types of air cleaners for gases and vapours

A

Two types of air cleaners for gases and vapours

DESTRUCTION METHOD - thermal incineration. gases or vapour are destroyed before discharge by burning

RECOVERY METHOD - e.g. adsorption. contaminated air passes through filters that remove gases and vapours. activated carbon filters are the most common however you need to change the filter, the filter fails on saturation (drips), carbon can develop hot spots that need heat detectors and fire extinguishing systems

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17
Q

What factors need to be considered when selecting a fan

A

What factors need to be considered when selecting a fan

  • -the type of substance
  • -flammability (gas vapours) or combustibility (solids)
  • -airflow required
  • -system resistance characteristics (balance, not pushing harder than the other)
  • -fan pressure
  • -space limitations
  • -method for mounting the fan
  • -operating temperature
  • -noise levels
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18
Q

Name Three types of fan

A

Name three types of fan:
PROPELLOR -general or dilution ventilation, light, inexpensive, don’t produce much pressure and operate best against low resistance.
AXIAL -not suitable for dust, compact, do not develop high pressures (gases and vapours)
CENTERFUGAL - common in LEV systems, generate large differences in pressure and can produce airflows against considerable resistance

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19
Q

What are the factors that can reduce the effectiveness of an LEV

identify the reasons why the EFFICIENCY of a local exhaust ventilation (LEV system may gradually deteriorate under normal use conditions (10)

A

the factor that can reduce the effectiveness of and LEV are:

  • -POOR DESIGN wrong hood for type and size of containment cloud or underpowered fan unable to capture cloud
  • -POOR USE - system not switch on, wrong hood placement
  • -UNAUTHORISED MODIFICATION -can imbalance a system and adversely affect air flows
  • -INADEQUATE MAINTENANCE -damaged ducting, congested filters and damaged fan blades will compromise the effectiveness of the LEV
  • -CHANGES OF WORK ACTIVITY - generating more contaminant than the LEV was designed to cope with
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20
Q

What is general (dilution) ventilation

A

What is general (dilution) ventilation
It’s used to define the flow of air into and out of a working area.
–it provides fresh air
–removes excess heat
–dilutes and removes offensive odours
–dilutes and contaminants caused by workplace activities

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21
Q

What are the two types of General (dilution) ventilation

A

What are the two types of General (dilution) ventilation

NATURAL VENITLATION-relies on wind pressure and temperature differences to move fresh air through a building. Not controllable

FORCES OR MECHANICAL VENTILATION-which uses mechanical supply and or extraction to provide fresh air and is controllable.

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22
Q

What must you make sure when you use general (dilution) ventilation?

A

What must you make sure when you use general (dilution) ventilation?

that the person is not in the air flow of the contaminant.

i.e. Stand in front of the air flow with contaminant in front facing the direction that the particles would leave out the window/door of.

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23
Q

What should you inspect on an LEV

A

What should you inspect on an LEV.

  • -any moving parts that may wear such as fan bearings or filter shakers
  • -non moving parts, such as hoods, ductwork and seals
  • -parts that deteriorate with use, such as filters or flexible ducting
  • -items that need regular attention such as filters that need replacing or removing sludge from a wet scrubber
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24
Q

What Qualitative measurements can you use to access the performance of an LEV

Describe the various tests that could be used to access the efficiency of a LEV system (12)

A

Observation
–dust lamp or Tyndall illumination makes the particles visible. shows the density and movement of particle clouds in the lights path.
–smoke pellets, smoke tubes or smoke generators
they can both
–show the size, velocity and behaviour of airborne contaminant
–identify capture zones and boundaries
–confirm containment within a hood
–identify draughts, their direction and size
show the general movement of air
cameras, fibre optic camera and boroscopes can be used inside the LEV

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25
Q

What Quantitative measurements can you use to access the performance of an LEV

Describe the various tests that could be used to access the efficiency of a LEV system (12)

A

What Quantitative measurements can you use to access the performance of an LEV
INET - FACE OR CAPTURE VELOCITY - booth is divided into rectangles and air velocity is measured at a series of positions across the booth face (vane anemometer)
DUCT - TRANSPORT DUCT VELOCITY - measured in a straight section of duct ( thermal anemometer is suitable if air velocity if less than 3ms-1 or pitot static tube)
FAN.AIR MOVER - fan direction and speed, pressure difference across the fan and the volume flow rate
AIR CLEANER - FILTERS - pressure difference across the filter. WET SCRUBBER - pressure difference at the inlet and outlet
AIR SAMPLING - testing emission levels from the exhaust, calibrated instruments

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26
Q

What instruments can you use to test an LEV

A

What instruments can you use to test an LEV

VANE ANEMOMETER
THERMAL ANEMOMETER
PITOT STATIC TUBE

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27
Q

VANE ANEMOMETER

A

VANE ANEMOMETER
–USE ON THE OUTSIDE ONLY AS WOULD OBSTRUCT AIRFLOW
–NO OF ROTATIONS OF VANE COUNTED OVER TIME
–VELCOITY CALCUATED IN METER PER SECOND (0.12-25MS-1)
FACE VELOCITY MEASUREMENT

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28
Q

THERMAL ANEMOMETER

A

THERMAL ANEMOMETER

  • -RATE OF HEAT LOSS IS RELATED TO FLOWOF AIR
  • -VELOCITIES MEASURED 0-30MS-1
  • -TEST DUCTWORK AND CORRECT POSITIONING OF THE HOOD
  • -MORE SUITABLE FOR DUCT VELOCITIES LESS THAN 3MS-1
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29
Q

PITOT STATIC TUBE

A

PITOT STATIC TUBE

  • -THINK OF THE BIT ON THE PLACE WING
  • -PRESSURE GUAGE, VELOCITY PRESSURE WHICH CAN THEN BE CONVERTED TO VELOCITY
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30
Q

What law relates to examining and testing an LEV

outline the requirements relating to the statutory examination…………… and testing of LEV systems, specifying the information that should be recorded following each thorough examination. (8)

A

What law relates to examining and testing an LEV

regulation 9 of the CoSHH regulations 2002 requires a thorough examination and test of a LEV system to be carried out

  • -by a competent person
  • -once in every period of fourteen months ( 1 month for JUTE)
  • -keep a record for 5 years

high hazard proves require more frequent through examination
includes airflow and pressure measurements
check on control effectiveness
exposure management
test the LEV against the performance record in the commissioning report

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31
Q

what are the three stages to be considered for a thorough examination and testing of an LEV

A

what are the three stages to be considered for a thorough examination and testing of an LEV
Stage 1 - visual inspection - good working order
Stage 2 - measure and examine the technical performance, check conformity with commissioning report
Stage 3 - assess whether the control of worker exposure is adequate

32
Q

What is in the content of an LEV report

outline the requirements relating to the statutory examination and testing of LEV systems, specifying the information that should be recorded following each thorough examination. (8)

A

What is in the content of an LEV report:
ADMIN - name address of the employer, date of examination and test, identification and location of LEV
PROCESS AND HAZARDOUS SUBSTANCE
CONDITIONS OF TEST - normal production or special
DIAGRAM OF LEV LAYOUT AND TEST POINTS
CONDITION of the LEV, serial numbers photos
ITS INTENDED OPERATING PERFORMANCE
METHODS USED - what was used to judge performance visual, airflow measurements, where you took measurements
RESULTS - air sampling
COMMENTS - operator use and wear and tear
TESTER DETAILS - name address job title of person doing the test, signature
DETAILS - of repairs adjustments needed to make the LEV effective
CRITICAL DEFECTS
measure and check against the commissioning report
KEEP FOR 5 YEARS

33
Q

The personal protective equipment at work regulations 1992

Definition:

A

The personal protective equipment at work regulations 1992
Definition:

all equipment (including clothing affording protection against weather) which is intended to be worn or held by a person and which protects that person against one or more risks to his health and safety.

gloves, eye protection and respiratory protective equipment.

34
Q

The personal protective equipment at work regulations 1992

Key regulations

A

The personal protective equipment at work regulations 1992
Key regulations
Regulation 4 PROVISION OF PPE
Regulation 5 CAPABILITY OF PPE
Regulation 6 ASSESSMENT OF PPE
Regulation 7 MAINTENANCE & REPLACEMENT OF PPE
Regulation 8 ACCOMMODATION FOR PPE (storage)
Regulation 9 INFORMATION, INSTRUCTION & TRAINING
Regulation 10 USE OF PPE
Regulation 11 REPORTING LOSS OR DEFECT

Section 9 HASAW 1974 - cant chare for PPE

35
Q

What other regulations apply to PPE

and what regulations then don’t apply

A

What other regulations apply to PPE
and what regulations then don’t apply

These specific regulations take precedent over PPE at work regs 1992
The control of lead at work regulations 2002
The control of asbestos regulations 2012
The control of substances hazardous to health regulations 2002 (as amended)

don’t apply
4 of the PPE at work regulations ( provision of PPE)
Regulations 6-12 of the PPE at work regulations

36
Q

Why is PPE the last resort

A

Why is PPE the last resort

Does not meet regulation 4 MHSAW or schedule 1, collective over individual

  • -only protects the person wearing it
  • -actual level of protection is difficult to access
  • -if used incorrectly or badly maintained the wearer is unlikely to receive adequate protection
  • -uncomfortable
  • -may interfere with work, limits viability or movement
37
Q

Effective protection from PPE is only achieved by

A

Effective protection from PPE is only achieved by

  • -suitable PPE
  • -correctly fitted PPE
  • -maintained
  • -properly used
38
Q

When accessing PPE what factors need to be considered

What ergonomic assessment of PPE is needed

Outline the factors that should be considered in the selection of PPE (10)

A

Outline the factors that should be considered in the selection of PPE

THE JOB AND THE RISKS low oxygen concentrations may require breathing apparatus, physical effort needed to do the job, duration PPE needs to be worn, requirements for visibility and communication.
THE ENVIRONMENT - the surrounding conditions e.g. weather if working outside, heating, noise, atmospheric conditions
THE PERSON- their health, allergies, musculoskeletal problems, max protection min discomfort
CE MARKING
TYPE AND LEVEL OF PROTECTION REQUIRED- risk assessment will indicate the type of substance and its nature (corrosive, toxic), the form (solid, gas) route of entry into the body, concentration of the substance
COMPATIBILITY - more than one risk, more than 1 item of PPE therefor they must work together or be compatible
INDIVIDUAL ISSUES - take into account any existing health issues (asthma, eczema), young workers, pregnant, religious principles (turbans), glasses and contacts
FIT - designed for the average person, different sizes might be needed

39
Q

PPE and Consultation

A

PPE and Consultation

………….

40
Q

PPE training

Identify the content of a training programme that will assist employees to use the PPE correctly (5)

A

PPE training
PPE at work Reg 9 INFORMATION, INSTRUCTION & TRAINING

must be training in

  • -proper use of PPE
  • -how to correctly fit and wear PPE
  • -what its limitations are

THEORETICAL TRAINING

  • -an explanation of the risks present and why PPE is needed
  • -the operation, performance and limitations of the equipment
  • -instructions on the selection, use and storage of PPE. Written operating procedures e.g permits to work involving PPE should be explained
  • -factors which can affect the protection provided by the PPE such as other protective equipment, personal factors, working conditions, inadequate fitting and defects, damage and wear
  • -recognising defects in PPE and arrangements for reporting loss or defects

PRACTICAL TRAINING - KISS

  • -practice putting on, wearing and removing equipment
  • -practice in inspection and testing PPE before use
  • -practice on how to maintain PPE, cleaning and replacement
  • -instruction in the safe storage of equipment
41
Q

What does RPE mean

A

What does RPE mean

Respiratory Protective Equipment

42
Q

What are the two types of RPE

A

What are the two types of RPE
RESPIRATORS - filter contaminants out of the air so the wearer can breath clean air

BREATHING APPARATUS - delivers a supply of breathable air from an uncontaminated source

43
Q

What do you need to consider when selecting RPE

A

What do you need to consider when selecting RPE

  • -the level of air present in the air to be breathed
  • -the presence of toxic chemicals that may pose an imminent risk to life

a BA should be specified where the level of oxygen in the air is lower than 20% or their is an imminent risk to life

44
Q

Limitations of RPE face pieces

A

Limitations of RPE face pieces
MASKS - tight fitting face-pieces rely on a good seal
HOODS, HELMETS, VISORS, BLOUSES, SUITS - loose-fitting face-pieces which reply on enough clean air being provided to the wearer to prevent contaminant leaking in. they are only used on fan-powered respirators and or air fed equipment

45
Q

Respirators

A

Simple filtering respirator - disposable dust masks, exchangeable filter cartridges
Power assisted respirators - use hoods , helmets, visors or blouses with a battery powered filter unit. the achieve a high level of protection as in addition to the filtration unit the positive airflow to the breathing zone prevents the ingress of contaminated air. Positive pressure - leaks outwards

46
Q

Types of filter on a respirator

A

Types of filter on a respirator
Particle Filters - trap and hold particles (dust, mist, micro-organisms) from the air flowing through them. Used for solids particles, liquid mists and droplets. NOT gasses or vapours, mists or sprays or O2 deficient

Gas/ Vapour Filters - to remove gases or vapours, have t time limit. do not protect against particles or O2 deficient

Combined Filters - both particles and specific gas or vapour.

47
Q

What are the different types of filter efficiency

A

What are the different types of filter efficiency

P1- LOW EFFICIENCY - PF4
P2- MEDIUM EFFICIENCY - PF10
P3- HIGH EFFICINECY - PF20 or PF 40

48
Q

What are the classifications for gas and vapour filters

A

What are the classifications for gas and vapour filters

based on how much of the specified contaminant they can hold in a laboratory test condition.
Class 1 low capacity
Class 2 medium capacity
Class 3 high capacity

A2P3 filter = an organic vapour filter and a high efficiency particle filter

A: Organic vapour filter
2: medium capacity
P3: High efficiency particle filter

P: particulate
E: Sulphur Dioxide

49
Q

How do you know when you need to change a gas or vapour filter

A

How do you know when you need to change a gas or vapour filter
works with activated charcoal (400oc) once the charcoal is full it drips. However it fails when this happens. Headaches are also an indication. normally last 40 hours

50
Q

Breathing Apparatus relies on what

A

Breathing Apparatus relies upon a supply of fresh air either

  • -from an air hose whose outlet is in an uncontaminated atmosphere and relies on the operators lung power to draw in the fresh air (length of air hose)
  • -from an air line using a compressor to provide a powered supply of filters breathable air
  • -self contained breathing apparatus which may be open or closed circuit

OPEN circuit - from a cylinder worn on a back pack or remote location
CLOSED circuit - removes excess carbon dioxide from exhaled air which is then re-breathed - EMERGENCY ONLY

51
Q

KEY ELEMENTS OF SUCCESSFUL RPE

A

KEY ELEMENTS OF SUCCESSFUL RPE

  • -eliminate risks if practicable
  • -justify RPE use
  • -is oxygen deficiency possible
  • -identify materials and risk band
  • -decide dustiness/volatility
  • -decide on level of protection required
  • -consider work related factors
  • -consider individual wearer factors
  • -select RPE
  • -train those involved
  • -set up maintenance system
  • -issue and use RPE
  • -supervise use of RPE
52
Q

Suitability of RPE

A

Suitability of RPE

1) adequate
2) matched to the wearer, the task and the working environment
3) minimum impediment
4) without additional risks due to the PPE

53
Q

How can RPE be considered adequate

A

how can RPE be considered adequate
if it can provide a level of protection required to reduce the exposure to comply with the law (CosHH, Lead, Asbestos & PPE)

54
Q

How do you justify PPE

A

How do you justify PPE:

  • -where an inhalation exposure risk remains after other reasonable controls have been put in place
  • -short-term or infrequent exposures where other controls at source are not reasonably practicable
  • -while putting in place other control measures (interim measures)
  • -emergency escape for safe exit from an area where hazardous substances may be released suddenly in the event of control system failures e.g. a chlorine tank
  • -emergency work or temporary failure of controls where other means of controls are not reasonably practicable
  • -where emergency rescue by trained personnel is necessary
  • -or to provide additional protection should other control measures fail to operate
55
Q

How do you select RPE

Outline the factors that should be considered in the selection of RPE (10)

A

How do you select RPE

1) Chemical and toxicological related factors
- -form of the substance (solid, liquid, gas)
- -nature of the hazardous substance (toxic, biological, dust in sufficient quantities)
- -routes of entry to the body (inhalation, ingestion)
- -effects on the body (acute, chronic)
- -Oxygen levels - 21% ok, below 19% deficient, more than 21% enrichment (don’t weld)
- -confined spaces

2) Task related factors
- -Work rate , heavy breathing, sweating (face mask might slip and leak)
- -wear time- longer period over 1 hour, discomfort
- -abnormal temp
- -power tools used by compressor should be able to supply both the tool and the BA
- -vision, misting scratch (think racing driver and tear off visors)
- -clarity of communication, radio
- -mobility, trailing hose, trip hazard
- -congested work area- select small and lighter RPE

3) Worker related factors
- -facial hair - beard, religion or wigs!
- -facial markings, moles
- -spectacles
- -other protection, eye, hearing, head might interfere so make sure they can be combined and do the right job
- -medical conditions, weak heart, hearing defects, asthma, cough colds and pregnancy

56
Q

Explain the meaning of the term ‘assigned protection factor (apf)’ (4)

who does this

A

Explain the meaning of the term ‘assigned protection factor (apf)’ (4) who does this

Assigned protection factor APF
The APF is the level of respiratory protection that can realistically be expected to be achieved in the workplace by 95% of adequately training and supervised wearers using a properly functioning and correctly fitted respiratory protective device.

calculated under test conditions

air borne contamination (50mg/m3) divided by the level that would be breathed (5mg/m3in) the APF would be 50/5=10

The manufacturer

57
Q

What is an MPR and How do you calculate and MPR

A

What is an MPR and How do you calculate and MPR

The minimum protection required (MPR) from a specific RPE can be calculated by measuring the workplace concentration outside the face piece of the RPE and dividing it by the maximum allowable concentration inside the face piece of the RPE (i.e the WEL)

the Assigned protection factor APF of the selected equipment should be higher than the calculated minimum protection required MPR

58
Q

in relation to RPE
Explain why respiratory protective equipment may not afford the level of protection in practice that is claimed by the manufacturer (10)

A

in relation to RPE
Explain why respiratory protective equipment may not afford the level of protection in practice that is claimed by the manufacturer (10)

this maybe because

  • -poor airflow
  • -reduction in battery power
  • -fitting the incorrect cartridge
  • -failure to replace a saturated cartridge
  • -equipment incorrectly fitted or incompatible with other PPE
  • -the presence of other contaminants decreasing saturation time
  • -inadequate training/attitude to PPE
  • -poor maintenance
  • -inadequate storage
  • -inadequate supervision to ensure use
  • -damage occurring
  • -not manufactured to the appropriate standard
59
Q

In relation to RPE
Explain why levels of exposure to an airborne contaminant may be higher in practice than those theoretically obtained by the application of an ‘apf’ (14)

A

In relation to RPE
Explain why levels of exposure to an airborne contaminant may be higher in practice than those theoretically obtained by the application of an ‘apf’ (14)

60
Q

In relation to RPE
calculate the minim ‘apf’ value for RPE required to provide protection against an airborne contaminant that has a concentration in the air of 15mg/m3 and a workplace exposure limit of 0.1mg.m3

A

In relation to RPE
calculate the minim ‘apf’ value for RPE required to provide protection against an airborne contaminant that has a concentration in the air of 15mg/m3 and a workplace exposure limit of 0.1mg.m3

15/0.1 = 150

61
Q

Explain the content of the HSE’s RPE selector tool

A

Explain the content of the HSE’s RPE selector tool
(risk assessment)
Step 1) admin - company name, work environment, duration, frequency, work details
Step 2) control measures in place, totally enclosed process and handling systems, LEV, Partial enclosure, general ventilation, Bunds to limit the spread if leak occurs (confined space, oxygen deficiency, substance release & reason for PPE - residual risk, short duration work, emergency escape, interim measure, rescue)
Step 3) determine the hazard group of the substance/preparation - safety data sheet, HSG53 are needed to complete this step
Step 4) user details, facial hair, markings glasses, other protection, medical conditions

62
Q

What is a face fit test for RPE and what are the requirements for it

A

What is a face fit test for RPE and what are the requirements for it

should fit each individual correctly - tightfitting seal

the requirement for RPE face piece testing is described in the ACOP supporting:
CoSHH 2002 substances
CLAW 2002 lead
CAW 2012 asbestos

63
Q

What are the two types of RPE testing

A

What are the two types of RPE testing

Qualitative - subjective, can the wearer detect the test agent (smell odour test)
Quantitative - ratio of a substance measured outside of a RPE when compared to a substance from within the RPE PORTACCOUNT machine

64
Q

Storage and Maintenance of RPE

A

Storage and Maintenance of RPE

  • -pre-use inspections
  • -examination testing - operating as intended
  • -cleaning and disinfection
  • -repair and replacement
  • -record keeping
  • -disposal of contaminated equipment
  • -clean, safe storage facilities
65
Q

Misuse of RPE

A

Misuse of RPE

  • -wearer compatibility, hair, face fit test
  • -compatibility with other PPE, glases
  • -maintenance and cleaning, seals, dirt
  • -training/supervision failure, upside down
66
Q

what are the 4 main groups of substances that can cause skin problems

A

what are the 4 main groups of substances that can cause skin problems

CORROSIVE SUBSTANCES lead to burns
IRRITANT SUBSTANCES lead to irritant dermatitis
SENSITISING SUBSTANCES can lead to allergic contact dermatitis
OTHERS skin caner (engine oil)

67
Q

what factors need to be considered when selecting gloves

A

what factors need to be considered when selecting gloves

chemical resistance to the corrosive solution
chemical breakthrough time - the time a chemical takes to work through the glove (permeate)
type and duration of contact
level of dexterity and sensitivity required
length of glove
durability of the glove
suitable size range
employee allergies

permeation rate is the amount of substance/water that move through
degradation is damage of the glove material

68
Q

Limitations of gloves

A

Limitations of gloves

  • -only protect the wearer- do not remove the contaminant from the workplace
  • -maybe inconvenient/interfere with work
  • —uncomfortable
  • —restrict movement
  • —affect some touch
  • -may introduce new hazards e.g. latex
  • -must be properly maintained and used
  • -physical and environmental restrictions may adversely affect work rates
69
Q

when choosing Eye face protection what should be considered

A 
the nature of the hazard - spray dust
the risk factors - acid splashing in the face
intended use - be suitable for chemical
type of lens - clear , tinted
ocular performance
comfort and fit
compatibility with other PPE
70
Q

what are the other practical measures to increase the correct use of PPE apart from PPE

A

what are the other practical measures to increase the correct use of PPE apart from PPE

  • -management leading by example
  • -employees involved in the selection
  • -availability of a range of sizes
  • -sign for equipment
  • -issue on a personal bases
  • -provide adequate storage
  • -use signs posters and incentives
  • -discipline non use
  • -monitor effectiveness and replace with alternatives
71
Q

Explain why duct velocity is an important parameter to measure when assessing the efficiency of an LEV system (2)

A

Explain why duct velocity is an important parameter to measure when assessing the efficiency of an LEV system

……………..
if it doesn’t work drop contaminant, heavy block …..FINISH

72
Q

outline the methods that can be used to measure duct velocity in an LEV system (5)

A

outline the methods that can be used to measure duct velocity in an LEV system (5)

………thermal anemometer
pitot static tube
FINISIH………….

73
Q

Identify other parameters that may be measured to determine the overall efficiency on an LEV system (3)

A

Identify other parameters that may be measured to determine the overall efficiency on an LEV system

face velocity
duct
dust lamp
fan efficiency
sample air
measure the distance from the hood
FINISH...................
74
Q

outline the issues you would need to consider when assessing the adequacy and quality of the LEV report in order to provide relevant comments to the production manager (10)

A

outline the issues you would need to consider when assessing the adequacy and quality of the LEV report in order to provide relevant comments to the production manager

75
Q

describe the factors to consider when selecting, using and maintaining PPE to protect hands against a degreasing solvent (20)

A

describe the factors to consider when selecting, using and maintaining PPE to protect hands against a degreasing solvent (20)

NEBOSH DIPLOMA UNIT B (10 decks)

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