Occupation Health Risks in Construction. Control of Substances Hazardous to Health (COSHH) Dr Stephen Ross. CChem MRSC, Dip NEBOSH, Grad IOSH, AFOH

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1 Occupation Health Risks in Construction Control of Substances Hazardous to Health (COSHH) Dr Stephen Ross CChem MRSC, Dip NEBOSH, Grad IOSH, AFOH

2 COSHH & DSEAR? COSHH HAZARDOUS SUBSTANCES Flammable/explosive EXPOSURE CONTROL Wood dust- asthma/cancer ( LEV) Commercial gas - frost burns/asphyxiation DSEAR DANGEROUS SUBSTANCES Flammable/explosive PROCESS CONTROL Explosive atmospheres (LEV explosion vent) Zoning of areas/ suitability of equipment Control of static DSEAR is a technical area requiring a specific risk assessment

3 Non-flammable adhesive solution in a flammable propellant Extremely Flammable propellant

4 What is an explosion? Very rapid oxidation generating an overpressure that compresses the gas ahead of it Deflagration - subsonic- 220 mph ~ 0.5 bar (often referred to as a flash fire) Detonation supersonic 4500 mph ~ 20 bar Flame front compresses the vapour ahead of it above its auto-ignition temperature

5 Which will Burn? Solid Liquid Gas All of them

6 Terms Flash Point Ethanol 16 ⁰C LPG -60 ⁰ C (auto-ignition at 410 ⁰ C ) DME -41 ⁰ C VALUES are significantly lower if an aerosol!!!

7

8 Minimum Ignition Energy Carbon Disulfide <0.1 mj Acetone 1 mj Benzene 0.2 mj Toluene 0.2 mj LPG 0.46 mj Spray Paints Tensor grip Problem when relative humidity drops below 40 percent

9 0.04mJ - Spark threshold, visible in darkness 1.2 mj - Winter doorknob spark, small snap, can be felt (will ignite most vapours) 3.7 mj - Fairly nasty spark, louder snap. Ouch! 1000 mj = 1 J sever to unconscious

10 DSEAR Requirements Employers must: RISK ASSESSMENT put control measures in place to either Eliminate those risks or, where this is not possible, Minimise - likelihood of explosive atmosphere occurring and sources of ignition (Mitigate) plans and procedures to deal with accidents, incidents and emergencies involving dangerous substances

11 Minimum Ignition Energy Dusts Aluminum 10 mj Corn (2%moisture) 110 mj Epoxy Resin <10 mj Milk Powder 50 mj Sugar 30 mj Sulphur <10 mj

12 Where is the Castle in Newcastle? Friday 6 October 1854, in which a substantial amount of property in the two towns was destroyed in a series of fires and an explosion which killed 53 and injured hundreds Force of explosion threw debris ¾ mile and heard 40 miles away Granite blocks were thrown 370 metres

13 HAT, BOOTS AND Hi-VIZ INDESTRUCTIBLE!

14 BUT SO FAR ONLY CONSIDERED PHYSICAL HAZARDS AND INJURY

15 Hazardous Substances Fuel for plant & equipment (oil/petrol / diesel) Cement, plaster dermatitis, oil acne, Used engine oil - cancer chronic dermatitis Solvents, Paints, thinners Adhesives Sensitisers, allergic dermatitis, narcotic neuropathy - Harmful to fertility - Harmful to unborn - Carnogenic

16 Biological Hazards Weils Disease (Leptospirosis) Legionella

17 Risk assessments (Reg 6) Suitable and sufficient assessment of the risk created by that work to the health of those employees and of the steps that need to be taken to meet the requirements of these Regulations Includes storage and emergency plans Collecting manufacturers or suppliers data sheets and other information does not in itself meet the COSHH requirements to carry out an assessment.

18 Toxicology

19 Acute Toxicity Immediate Effect and often local You will often be aware of this but not always Corrosive Irritant Narcotic

20 Chronic Toxicity Effects not immediate by low repeated dose Often Systemic- not local

21 Employer must consider the possible enhanced harmful effects of combined or sequential exposures Additive Synergistic 1+1= 2 (xylene + toluene) = 10 (ethanol + Carbon tetrachloride) Potentiation 0+1 =10 (Carbon tetrachloride + isopropanol) other examples MEK & hexane

22 Take into account all relevant routes of exposure Skin absorption/eye contact Inhalation Ingestion Puncture of the skin

23 Bodies Defence Systems Skin/eyes Lungs Cardiovascular systems

24 Skin Waterproof - but not Chemical proof Dermatitus Unguentum M

25 Dust & Fibres Inhalable dust Respirable dust ( < 10 micron = 0.01 mm)

26 Asbestos- Pleural plaques, Asbestosis, Mesothelioma, RCS - Silicosis Wood dust - occupational Asthma & Nasal cancer Stainless steel welding fume lung cancer, nasal cancer Isocyanates - occupational Asthma Chronic Obstructive Pulmonary Disease (COPD)

27 Control exposure by measures that are proportionate to the health risk SO FAR AS IS REASONABLY PRACTICABLE

28 Hierarchy of COSHH assessment (Reg 7) Eliminate Substitute Collective Engineering measures first Local Exhaust Ventilation (LEV) Screening off Reduce number of personnel Reduce time of exposure PPE.

29 Control of Dust & Fumes -

30 PPE Where adequate control of exposure cannot be achieved by other means, provide, in combination with other control measures, suitable personal protective equipment.

31 Skin protection Barrier creams Organic Water based protection Limited protection

32 Gloves Need to be the correct size Need to be the correct type Need to be changed regularly- breakthrough time Need to remove them correctly!

33 PPE Combinations

34 Inhalation Protection DO NOT SMOKE in work area!! Dichloromethane Tensor Grip, Anti-spatter, Carbon monoxide normal metabolite Professional DCM paint strippers need HSE approved training

35 Dichloromethane is converted to Phosgene in cigarette. The odor detection threshold for phosgene is 0.4 ppm, four times the threshold limit value.

36 RPE Next speaker will deal with this!

37 an employer may issue personal protective equipment such as clothing, face shields, gloves etc, not because other control measures are inadequate on their own, but to provide employees with additional protection should any of those measures fail.

38 Good Industrial Hygiene NO FOOD or DRINKS in areas with Chemicals. Wash hands BEFORE going to the toilet Wash hands after going to the toilet Don t smoke and work with Chemicals. Even better just don t smoke A smoker exposed to asbestos is 50 times more likely to die from the result of the exposure.

39 the prohibition of eating, drinking and smoking in areas that may be contaminated by carcinogens; e.g. Welding fume, wood dust, chlorinated solvent vapour

40 Reg 8 Every employer who provides any control measure, ensure that, in the case of plant and equipment, including engineering controls and personal protective equipment, it is maintained in an efficient state, inefficient working order, in good repair and in a clean condition; and in the case of the provision of systems of work and supervision and any other measure, it is reviewed at suitable intervals and revised if necessary.. (2) Every employee shall make full and proper use of any control measure, other thing or facility provided in accordance with these Regulations and, where relevant, shall (a) take all reasonable steps to ensure it is returned after use to any accommodation provided for it; and (b) if he discovers a defect therein, report it forthwith to his employer. (implicit requirement to be able to detect is not working)

41 Reg 9 1) Every employer who provides any control measure shall ensure that, where relevant, it is maintained in an efficient working order, in good repair and in a clean condition. (2) Where engineering controls are provided, the employer shall ensure that thorough examination and testing of those controls is carried out (a) LEV at least once every 14 months, or for LEV used in conjunction with a process specified in Column 1 of Schedule 4, at not more than the interval specified (b) in any other case, at suitable intervals. (3) Where respiratory protective equipment (other than disposable respiratory protective equipment) is provided the employer shall ensure that thorough examination and, where appropriate, testing of that equipment is carried out at suitable intervals. (HSE guidance 3 months max) in the case of the provision of systems of work and supervision and of any other measure, it is reviewed at suitable intervals and revised if necessary BOHS P601

42 Records (4) Every employer shall keep a suitable record of the examinations and tests carried out and of repairs carried out as a result of those examinations and tests, and that record or a suitable summary thereof shall be kept available for at least 5 years from the date on which it was made. (5) Every employer shall ensure that PPE, including protective clothing, is: (a) properly stored in a well-defined place; (b) checked at suitable intervals; and (c) when discovered to be defective, repaired or replaced before further use. (6) Personal protective equipment which may be contaminated by a substance hazardous to health shall be removed on leaving the working area and kept apart from uncontaminated clothing and equipment. (7) The employer shall ensure that the equipment referred to in paragraph (6) is subsequently decontaminated and cleaned or, if necessary, destroyed.

43 Monitoring exposure Reg 10 when failure /deterioration of the control measures could result in a serious health effect, to be sure that a WEL is not exceeded as an additional check on the effectiveness of any control measure always in the case of the substances or processes specified in Schedule 5; ( 2 chemicals) when any change occurs in the conditions affecting employees exposure which could mean that adequate control of exposure is no longer being maintained, Where risk assessment determines it to be necessary Biological monitoring for isocyanate!

44 Health Surveillance Reg 11 Where:- a) the employee is exposed to one of the substances or processes specified in COSHH Schedule and there is a reasonable likelihood that an identifiable disease or adverse health effect will result from that exposure; or (b) the exposure is such that an identifiable disease or adverse health effect, reasonable likelihood that the disease or effect may occur AND there are valid techniques for detecting indications of the disease or effect And the technique is of low risk to employee

45 Noise Resp. Sensitiser/COPD Skin Irritants/sensitiser Vibration Vehicle drivers Chromium VI/hard wood Audiometry Spirometry/Urine Skin surveys Hav s Driver medicals nasal checks

46 Reg 12 Every employer who undertakes work which is liable to expose an employee to a substance hazardous to health shall provide that employee with suitable and sufficient Information, instruction and training containers and pipes marked in accordance with any relevant legislation listed in Schedule 7, the employer shall, Contents of those containers and pipes, together with the nature of those contents and any associated hazards, are clearly identifiable This overlaps with CLP Regs

47 Reg 13 in order to protect the health of his employees from an accident, incident or emergency related to the presence of a substance hazardous to health the employer shall ensure that (a) procedures, including the provision of appropriate first-aid facilities and relevant safety drills (which shall be tested at regular intervals), have been prepared (b) information on emergency arrangements, including (i) details of relevant work hazards and hazard identification arrangements, and (ii) specific hazards likely to arise at the time of an accident, incident or emergency, is available; and (c) suitable warning and other communication systems are established to enable an appropriate response, including remedial actions and rescue operations,

48 Any Questions?