CONFINED SPACE

HAZARD ASSESSMENTS

Andrew Ross,

City of Vancouver

Objectives – Participants will understand the importance of:

• Identifying Confined Spaces

• Documenting Confined Space Access and

Configuration

• Conducting Confined Space Hazard

Assessments

Objectives – Participants will understand the importance of:

• Confined Space HA and Contractor

requirements

• Confined Space Rescue

Hazard Assessment- What is it?

Definition:

• documentation and evaluation of

hazardous conditions

Hazard Assessment- What is it?

• How do we get in and out?

• What is in the confined space?

• How bad is it?

• Are we making it worse while working?

• How easily could we be rescued?

CS Hazard Assessment – the whole space

Identification

Access and configuration

Pre – entry hazards

Work task hazards

Rescue issues

Hazard assessment

Identification

Confined Spaces need to be identified:

By signage

Or be easily recognized

Access and Configuration - Where is it?

• Accurate description of location

– Address

– Location at address

– Floor plan

– Map

– GPS coordinates

– Photos

– Grouping of spaces is acceptable

Access and Configuration - What does it look like?

• Accurate description of entry point and

space

– Describe area around entry point – traffic!

– Describe entry point – dimensions and

orientation

Access and Configuration - What does it look like?

• Accurate description of entry point and

space

– Access into space – ladder?

– Internal configuration – sloped or slippery

floor

– Contents and equipment inside

Hazard Assessment

Two Part assessment process:

1. Pre-entry hazardous conditions

2. Entry conditions and work task hazards

Hazard Assessment

• What is the hazard? Oxygen deficiency

• Is it present? Yes - possibly

• Why (Pre-existing)?

– Sludge in bottom of chamber, bacteria can live in sludge and use up the oxygen.

– Rusty equipment in space

– Past monitoring had low O2 readings.

• How bad is it (pre-existing)?

– Oxygen deficiency hazard is high if no precautions are taken

Hazard Assessment

• What is the hazard? Oxygen deficiency

• Is it present? Yes

• Why (work task)?

– Need torch to cut bolts off of water meter.

– Need a power saw to cut bolts off of a water meter

– Need to paint water meter with alkyd spray paint

• How bad is it (work task)?

– Oxygen deficiency hazard is high if no precautions are taken

Hazard Assessment - Types of pre-entry hazards in

municipal CS

• Oxygen deficiency

• Methane gas

• Hydrogen sulfide gas

• Biohazardous aerosol (sewage aerosol)

• Biohazards

• Ingestion/ skin absorption hazard

• Tanks containing chemicals

Hazard Assessment - Types of pre-entry hazards in

municipal CS

• Traffic

• Engulfment (water, sewage, fill)

• Personal confinement

• Mechanical

• Electrical

• Hydraulic

• Structural weakness

• Fire/explosion

Lockout

Hazard Assessment - Types of pre-entry hazards in

municipal CS

• Fall

• Slip/trip

• Sharp objects

• Insects/ animals

• Noise

• Visibility/light level

• Heat or cold stress

• Radiation or laser

Hazard Assessment - Types of hazards created by

work in CS

• Biohazardous aerosols

• Silica dust

• PVC solvent/cement

• Hot work (NO2, CO, CO2, metal fume)

• Chlorine or by-products (chloramines)

Hazard Assessment - Types of hazards created by

work in CS

• Silicone sealant vapours (ammonia

ethanol)

• Epoxy

• Paint

• Plumbing solder

• Welding fume

Hazard Assessment - Types of hazards created by

work in CS?

• Noise

• Structural

• Electrical (non GFCI)

• Fire

• Engulfment

• Mechanical/physical

Hazard Assessment - Strategies

• First attempt started by non-qualified individual but checked by qualified individual

• Group similar spaces

• Group similar work tasks for grouped spaces

Hazard Assessment - Rescue Issues

• Location

• Internal barriers

• Point of entry details important

– axis of entry

– height

– dimensions

– shape

• Difficult Space-contact Rescue service

Hazard Assessment - Rescue Issues

• Plan for rescue before entry

• Ensure contractors plan for rescue of their

own staff they cannot rely on the local fire

fighters to rescue them.

Confined Space contractor coordination

5 ft

Questions...

Hazard Assessment – Sewer Wet well

• Oxygen deficiency

• Methane gas

• Hydrogen sulfide gas

• Biohazardous aerosol (sewage aerosol)

• Biohazards

• Ingestion/ skin absorption hazard

Hazard Assessment – Sewer Wet well

• Traffic

• Engulfment (sewage, gravity and force main sides)

• Personal confinement

• Mechanical

• Structural weakness (ladder rungs)

• Fire/explosion (methane or dumped solvents)

Hazard Assessment - Types of pre-entry hazards in

municipal CS

• Fall

• Slip/trip

• Sharp objects

• Insects/ animals

• Noise

• Visibility/light level

• Radiation (some sensors)

Questions...