LEV Testing

If you have local exhaust ventilation (LEV) systems, be they spray booths, welding hoods, exhaust slots on degreasing-baths or larger multi-point systems, the law says they must be thoroughly examined and tested at least every 14 months.

Typical test parameters:

• Visual inspection for damage or corrosion
• Pressure drop across fan
• Pressure drop across bag filters or other arrestment plant
• Pressure behind exhaust hoods
• Air flow rate through main system and branch ducts
• Air flow rate at booth face, or in front of exhaust hood
• Visualisation of air flow characteristics at contamination source or containment interface

Information provided by the examination & test:

• Is the systemikely to provide adequate control & containment?
• Does the system meet minimum standards of effective design and performance?
• Has there been any change in performance since the previous test?
• What action is necessary to achieve satisfactory performance?
• What maintenance/repairs will be needed to prevent forseeable loss of efficiency?
• Records must be kept 5 years
• HSE inspectors will always want to see them
• An essential element in defending compensation litigation