HSE LEV Project and HSG 258 Guidance

1. HSE LEV Project andHSG 258 Guidance John Saunders Health and Safety Laboratory

2. John Saunders • Principal scientist working in HSL with over 25 years in scientific research and development • Member of HSE MVR and LEV Project teams • Involved in guidance development including LEV and MVR • Represents HSE as a member of the BSI and CEN Technical Committee for: • Laboratory fume cupboards • Welding fume • Spray booths

3. Outline of presentation • The HSE LEV project • Why the need for the project • HSG 258 • Hood classification • Working zones and capture zones • LEV specification • Competency • LEV commissioning • LEV user manual and log book • Airflow indicators • LEV hood labels • The HSE LEV project (again)

4. Background – COSHH (1) • Control of Substances Hazardous to Health (COSHH) is the law that requires employers to control substances that are hazardous to health • One way in which you can prevent/reduce workers exposure is by providing effective control measures such as LEV – suite of controls • Many of the substances used at work (but not all) have Workplace Exposure Limits (WELs) which are enforced under COSHH • Further information on these can be found in HSE publication EH40/2005 Workplace Exposure Limits (WEL) (http://www.hse.gov.uk/pubns/books/eh40.htm).

5. Why the need for updated LEV guidance Quote from an Occupational Hygiene Inspector “Too often I see LEV plant maintenance records showing various details such as the direction of rotation of the fan, dimensions of ducting etc and pass the system for Reg 9 purposes even when dust/fume is pouring into the workplace/operators breathing zone”

6. Matching LEV to potential degree of over-exposure Extreme This gap in control effectiveness leads to respiratory and other diseases Substantial Increasing potential exposure Moderate Nominal Increasing LEV effectiveness

7. Possible reasons why LEV often fails to offer adequate respiratory protect Employers / employees over-optimistic about LEV capabilities Employers often don’t appreciate the extent of exposure risk Purchasing: Lack of a LEV specification TExT: Not done or Uncritical LEV Failure LEV Failure Poor design Inadequate checking and maintenance Poor / lack of commissioning

8. HSE LEV Project The HSE's LEV project had the overall aim of: To bring about a significant and measurable improvement in the coverage and effectiveness of engineering exposure controls, particularly LEV, in Great Britain

9. LEV Project actions: • Engaged relevant (supply-side) stakeholders • Write new guidance • Train, equip and instruct HSE inspectors • Create a Website & solicit case studies • Encourage and facilitate training and briefing • Plan and supervise relevant research • Continue stakeholder and other work for years

10. Pre HSG 258 • HSG 54: Maintenance, examination and testing of local exhaust ventilation • HSG 37: An Introduction to Local Exhaust Ventilation

11. LEV guidance aimed at suppliers HSG 258 “Controlling airborne contaminants at work: A guide to local exhaust ventilation” Priced publication £20.00 But free to download

12. Employers and employee guidance INDG 408 “Clearing the air: A simple guide to buying and using local exhaust ventilation” INDG 409 “Time to clear the air! A pocket guide to local exhaust ventilation (LEV)” Both free to download from the HSE LEV website

13. HSG 258

14. The three basic types of LEV hood Capturing (Capture) Enclosing (Contain and separate) Receiving (Receive, contain & empty)

15. Why classify LEV hoods? • Highlights the essential features of the different types of hoods • Design principles listed in HSG 258 • Helps assessors to think more logically and look more critically at LEV hoods • Note: some hoods may work in mixed-mode

16. Capture zone and working zone – for capture hoods only

17. LEV specification – employer • Identify all processes and sources to be controlled • The employer may need help with this • Work with supplier to minimise sources and arrange for best LEV application • Be clear of the requirements of the work process and the operator(s) • Are some/all standard processes with standard & effective LEV designs? • What benchmark(s) of control success are acceptable?

18. Supplier – Competence • See HSG 258, Appendix 1 – Legal requirements • Means having appropriate knowledge, capabilities and experience • Qualifications (eg P602) • Proven experience • Trade associations • Includes anyone who: • Designs or selects control measures • Checks, tests or maintains control measures • Supplies goods and services to employers.

19. Commissioning – HSG States: There are four stages to LEV commissioning: • Installation (if necessary), and verifying that the system was installed as designed; • Showing that the LEV system meets the specified technical performance; • Control effectiveness • Commissioning report - Reporting findings as benchmarks for management and maintenance of LEV performance and subsequent examinations and tests.

20. 3. Control effectiveness Three instances: • LEV design known to be effective (standard design applied to standard process) • LEV design shown qualitatively to be effective (Observation and qualitative tests suggest effective control) • LEV design appears adequate but effectiveness uncertain (qualitative and quantitative tests needed plus, potentially, supplementary RPE)

21. 3. Control effectiveness Qualitative includes: • Making particle clouds visible (Tyndall effect) • Making air movement visible with smoke • Insightful observations Quantitative includes: • Quantitative performance measurements (pressures, velocities, etc) and comparison with requirements • Air sampling of exposure and work room levels • Other; e.g. Containment testing (specialist technique)

22. 4. Commissioning report • Diagrams and system description, (inc test points) • LEV performance specification • Test results (pressures, velocities, control effectiveness) • Calculations • Written report of findings • Clear description of optimum operator behaviour • Transfer of relevant data to User Manual and Log Book

23. User manual

24. User manual requirements • Simple description (inc a diagram) • Performance information (design and commissioning) • Checking and maintenance schedule • Replacement parts (inc part numbers) • Common signs of wear and control failure • Instructions on how best to use the LEV • Detailed description of through examination and test

25. Log Book • Hoods, filter etc – static pressures (and velocities) • Physical condition of LEV system • Maintenance done and parts replaced • Operator use of LEV in-line with agreed working methods • Exposure control effectiveness

26. Airflow indicators

27. LEV hood label • Examiner should issue a simple label for every hood examined and tested. • Failure labels should be accompanied by a failure report

28. Criteria for a red label • No air flow • Failure of an enclosing hood to contain the contaminant cloud • Failure of a receiving hood to intercept or contain the contaminant cloud • Failure of a capture hood e.g. capture zone cannot encompass the working zone

29. The HSE LEV project (again) • New(ish) HSE LEV guidance • New(ish) HSE website • Train, equip and instruct HSE inspectors • Over 400 inspectors trained • Stakeholders engaged • BE&S new guidance • Institute of LEV Engineers (ILEVE) • Raised awareness • New/revised courses on LEV • P601 – revised • P602 – Basic Design Principles of LEV Systems • P604 – Performance Evaluation and Management of LEV Systems • BOHS Awareness course • BOHS Practical Management of LEV Controls

30. Thank-you for listening Any questions?