Health and Safety Executive

Control Strategies – Good Occupational Practice Hygiene Practice Julie Helps (Occupational Hygiene Inspector)

AGENDA

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Dusty tasks Hierarchy of control Adequate control Good work practices Extraction Respiratory protective equipment

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Respiratory allergens/irritants

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Cereal flours: wheat, rye, barley, hops, rice, maize

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Non cereal flours:buckwheat, soybean Enzymes: amylase, cellulase, xylanase Almonds, hazelnuts, sesame seeds Colour: eg carmine red

Respiratory allergens/irritants (contd)

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Spices

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Moulds: Alternaria, Aspergillus

Egg/milk powder Insects: flour beetle, flour moth, cockroach, granary weevil Heat

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Airborne dust is generated during:

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Throwing; Pouring; Sieving; Scooping; Blowing (compressed airlines); Vibrating; Brushing.

of dry ingredients

Some potentially dusty tasks

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Dispensing/weighing ingredients; Filling mixers/bins from bags/hoppers; Flour sack disposal; Mixing; Dividing/ moulding (hand/dough plant); Rolling by hand or dough/pastry brake; Lubricating tins/trays with flour; Cleaning.

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Video visualisation kit

Video visualisation of dusty activities

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Tearing the top off a flour sack

Dough/Pastry brake

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Pastry brake -folding pastry

Flour silo hopper

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Flour delivery from a silo

Dust cloud generated during flour delivery

Pneumatic seal missing

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The goal is to prevent or failing this, minimise exposure to flour dust, bread improvers etc

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Hierachy of control First and foremost consider elimination, substitution or enclosing the process to prevent exposure you can’t eliminate or substitute flour and bread improver in the product but can you substitute flour as a lubricant ? Eg. Use vegetable oil, semowen, chinese crumb Or

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provide teflon surfaces for hand work or chilled surfaces Or

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Provide grease proof paper on moulding tables and baking trays

Semowen- granule product

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Semowen used as a lubricant

Hierachy of control cont…

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Provide bread improver in granule, liquid or paste forms rather than as a powder;

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Enclose the dusty processes eg using enclosed transfer systems, automated dough plant lidded mixers

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Segregate dusty processes by location/time

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Dispensing/weighing room

segregated from main bakery area

New Reg 7.7 (a)-(c) Control shall only be considered to be adequate if the Principles of Good Control Practice are applied

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Any WEL is not exceeded

+ exposure is reduced as low as reasonably practicable for a carcinogen or an asthmagen

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The principles of good control practice Regulation 7.7 (a) Schedule 2a “To be effective in the long-term, control measures must be practical, workable and sustainable”

“Good practice…can be encapsulated in eight generic Principles which consist of a package of hardware and soft ware controls. All the principles must be applied to obtain effective and reliable control.

Principles of good control practice Regulation 7.7 (a) Schedule 2a

(a) Design and operate processes and activities to minimise emission, release and spread of substances hazardous to health. (b) Take into account all relevant routes of exposure – inhalation, skin and ingestion – when developing control measures. (c) Control exposure by measures that are proportionate to the health risk.

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Principles of good control practice continued.. (d) Choose the most effective and reliable control options that minimise the escape and spread of substances hazardous to health; (e) Where adequate control of exposure cannot be achieved by other means, provide, in combination with other control measures, suitable personal protective equipment; (f) Check and review regularly all elements of control measures for their continuing effectiveness.

Principles of good control practice continued… (g) Inform and train all employees on the hazards and risks from substances with which they work, and the use of control measures developed to minimise the risks; (h) Ensure that the introduction of measures to control exposure does not increase the overall risk to health and safety.

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Work Place Exposure Limits (WELs) For Flour Dust relate to personal exposure to total inhalable dust

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8 hour time weighted average (TWA) =10mg/m3 15 minute time weighted average (TWA) = 30mg/m3

(WELs must not be exceeded) the flour dust WELs are not health protected limits Since flour is an asthmagen exposure must be reduced as low as reasonably practicable

If the principles of good control practice are implemented then in my opinion it is reasonably practicable to reduce exposure to flour dust to less than 2mg/m3 (8 hour TWA) Other countries 8 hour TWA limits: USA- 0.5 mg/m3; Netherlands-1 mg/m3, Sweden 3 mg/m3, Germany 4 mg/m3

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Principles of good control practice

Firstly implement good work practices

Ten top tips for bakers:

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Handle flour and powdered products carefully. Minimise the use of dusting flour. Dropping flour from height or throwing with force will cause dust to be thrown up;

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Use dredgers or sprinklers to apply flour rather than hand throwing;

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Avoid spillages of flour and where spillages occur clean them up immediately;

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Ten top tips continued…

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Take care to avoid raising dust when loading ingredients into mixers;

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Start up mixers on slow speed until wet and dry ingredients are combined;

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Avoid damage to ingredients bags; Minimise the creation of airborne dust when folding and disposing of of empty bags;

Ten top tips continued..

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Avoid the use of compressed airlines for cleaning;

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Do not use brushes to dry sweep dust as they cause high levels of airborne dust. Use high efficiency vacuum cleaners for general cleaning;

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Wear a suitable respirator for any essential, short term, dusty tasks.

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Provision of extraction/RPE

If good practice alone does not reduce exposure sufficiently then well designed engineering controls and or RPE will be needed.

Provision of extraction

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Extraction at the mixing bowl CE FL01 Immaterial lid -used for addition of dry ingredients

Immaterial lid dust extraction specification

Costs ~£100 to make with existing extract collector system

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Stand alone dust collector

Immaterial lid without extraction on

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Immaterial lid with extraction on

70% reduction in exposure

Laminar flow booth for emptying sacks or weighing

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Sack emptying tipping enclosures

Sack tipping point

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Sack compactor

Extracted silo weigh hopper

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Flour hopper enclosure

Extraction for flour dusting during hand work or dough brake

Extracted bench

More effective to use an open fronted extracted cabinet

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Ineffective extraction at dough/pastry brake cont..

Ineffective extraction at dough/pastry brake

Capture zone

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Ineffective extraction at dough/pastry brake cont..

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Extracted cabinet for weighing and handling bread improvers

For small scale flour dispensing/weighing an extracted hood may be sufficient

sack tipping into a container

at weighing scales

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Extracted booth

required if substantial dispensing/weighing/sieving is conducted

Atex regulations/ guidance on vacuums • •

Flour is an explosible dust

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For bakeries-ideally Atex compliant vacuum

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If using small commercial vacuum, use one with at least 2 filters (preferably 3) in series

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Do not use domestic vacuums

Atex certified vacuum in hazardous area (zones 20-22)

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Atex regulations/ guidance on vacuums •

Do not use aluminium tools

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Avoid use of wire reinforced hoses

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Ensure wet materials are not picked up

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Empty dust bag regularly

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Change filters regularly

Periodically, competent person to inspect motor for dust and thoroughly clean

Respiratory protection When is it appropriate to wear RPE:

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Short terms dusty tasks where extraction is not reasonably practicable or extraction is not sufficient Eg. Weighing; sieving, cleaning machinery and spillages, emptying dust collector units

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Respirators Disposable respirators

CE marked –EN149:2001

FFP1, FFP2, FFP3 APF 4 10 20

Respirators continued.. Particulate Filtering half mask

EN405 (1993)

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Tight fitting respirators What ever mask is selected it must pass 3 tests:

(i) It must provide adequate protection; (ii) It must fit the user properly; (iii) It must be compatible with any other protective equipment being worn. It is a legal requirement under COSHH to fit test tight fitting respirators

Qualitative Fit Testing -Bitrex or Saccharine test agent

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Ambient Particle Counting - employs the ambient air particles as the challenge - fit factors calculated from the measured particle concentration

Tight fitting respirators are unsuitable for people with facial hair

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Powered air hood

Loose fitting so does not require fit testing

EN 146

Powered visor

battery pack and filter

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Inform and train all employees principle (g)

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For control measures to be effective people need to be motivated to use them properly.

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They need to know what the health risks are to understand why the control measures are important.

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It is essential to involve the workers and supervisors in identifying workable practices to minimise exposure

Any Questions?

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