HSE Reminds Fixed Gas Detector Users to Revisit Alarm Settings

A new document from Britain's OSHA agency says setting alarm points "should not be 'fit and forget'" because initial alarm set-points may be adjusted up or down due to process-related events and instrument characteristics.

A new document published by Britain's Health and Safety Executive reminds users of toxic gas detectors about good practices when setting alarm points. It points out guidance is available on the HSE website for setting alarm levels for predominantly flammable gas detectors, but not for toxic gas detectors (although alarm levels are specified for certain gases in specific industries, such as chlorine plants and hydrogen sulfide offshore). "There is a need, therefore, to produce a framework by which the actual intended function of the toxic gas detection system can be established and, following on from that, which factors need to be considered to set appropriate alarm levels in order to carry out detection and warning," it states.

A key point in the document is the reminder for employers using fixed toxic gas detectors that setting alarm points "should not be 'fit and forget'" because initial alarm set-points may be adjusted up or down due to process-related events and instrument characteristics. "This requires analysis of the data over a suitable period," it adds.

The document also says guidance found in standards, such as BS EN 45544-4 relating to toxic gas detectors, "is not comprehensive enough. While each application of toxic gas detector is usually different from the others, general background information and guiding principles would assist HSE inspectors and safety practitioners."

The document lists 13 factors that relate to setting an alarm point:

1. Whether detectors should be fixed and/or whether personnel should be issued with portable, which includes personal, detectors.
2. The location of the fixed detector and whether the work area is occupied or unoccupied.
3. Whether the fixed detector is a point or open-path (also known as beam or line of sight detectors) detector.
4. Whether egress is difficult and/or time-consuming or there is an emergency.
5. Whether Workplace Exposure Limit (WELs), other Exposure Limit values, or other health-based levels (e.g., Immediate Danger to Life and Health -- IDLH) exist.
6. Instantaneous or time-weighted average (TWA) alarm.
7. Background variations and events from the process, which may trigger "spurious" alarms.
8. Effects of interferents.
9. False alarms caused by instrumental effects.
10. The potential rate of gas buildup (considering short-term peaks in point 7).
11. Time to alarm of the detection system.
12. Number of alarm levels (e.g., high and low levels).
13. Mixture of gases/vapors.

Download Center

HTML - No Current Item Deck
  • Safety Management Software - Free Demo

    IndustrySafe Safety Software’s comprehensive suite of modules help organizations to record and manage incidents, inspections, hazards, behavior based safety observations, and much more. Improve safety with an easy to use tool for tracking, notifying and reporting on key safety data.

  • Create Flexible Safety Dashboards

    IndustrySafe’s Dashboard Module allows organizations allows you to easily create and view safety KPIs to help you make informed business decisions. Our best of breed default indicators can also save you valuable time and effort in monitoring safety metrics.

  • Schedule and Record Observations

    IndustrySafe's Observations module allows managers, supervisors, and employees to conduct observations on employees involved in safety critical behavior. IndustrySafe’s pre-built BBS checklists may be used as is, or can be customized to better suit the needs of your organization.

  • Why Is Near Miss Reporting Important?

    A near miss is an accident that's waiting to happen. Learn how to investigate these close calls and prevent more serious incidents from occurring in the future.

  • Get the Ultimate Guide to Safety Training

    When it comes to safety training, no matter the industry, there are always questions regarding requirements and certifications. We’ve put together a guide on key safety training topics, requirements for certifications, and answers to common FAQs.

  • Industry Safe
comments powered by Disqus

OH&S Digital Edition

  • OHS Magazine Digital Edition - June 2019

    June 2019

    Featuring:

    • ASSP SAFETY 2019 PREVIEW
      New Orleans Networking
    • NATION SAFETY MONTH
      Heed These Summer Safety Tips
    • TRAINING
      Education, Skill Development, and Behavior Change
    • SAFETY MANAGEMENT
      What Good Looks Like
    View This Issue

Bulwark Quiz