A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Explosion-proof cameras require documented, periodic maintenance inspections to remain compliant with their certifications. The certification that allows equipment to operate in a classified area assumes the equipment maintains the condition it was in when certified — corrosion, impact damage, modified flame paths, or incorrect replacement parts can all invalidate that certification silently. This guide provides a complete inspection and maintenance checklist based on IEC 60079-17 and NFPA 70B requirements, along with documentation templates for your compliance records.
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
Why Explosion-Proof Camera Maintenance Is a Compliance Issue
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Unlike standard cameras where maintenance is purely about functionality, explosion-proof camera maintenance is a safety and legal compliance issue. IEC 60079-17 (Explosive atmospheres — Electrical installations inspection and maintenance) establishes the framework for maintaining certified equipment. NFPA 70B (Recommended Practice for Electrical Equipment Maintenance) provides complementary guidance for North American facilities.
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Facilities that cannot demonstrate documented inspection records risk:
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
- Voided equipment certification — if the equipment’s condition has deviated from its certified state
- OSHA PSM (Process Safety Management) findings — inadequate maintenance records are a common PSM audit finding
- Insurance claim denial — following incidents in areas where maintenance records cannot demonstrate compliance
- Criminal liability — if equipment failure contributes to a fatality in a classified area
Three Types of Inspection
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. IEC 60079-17 defines three inspection levels with increasing thoroughness:
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
| Inspection Type | Description | Frequency | Enclosure Open? |
|---|---|---|---|
| Visual | External check without opening — obvious damage, corrosion, missing parts | Quarterly (or per facility schedule) | No |
| Close | Thorough external check — fastener torques, cable gland condition, debris | Annually | No (or covers removed only) |
| Detailed | Internal inspection — flame paths, wiring, component condition | Every 3–5 years (or per risk assessment) | Yes (requires hot-work permit or isolation) |
Quarterly Visual Inspection Checklist
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Complete and record in your maintenance log. Mark each item Pass (P), Fail (F), or Not Applicable (N/A).
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
Housing Condition
- No visible cracks, dents, or deformation to housing body
- No missing or loose bolts or fasteners visible externally
- No corrosion breaching housing surfaces (surface rust is different from through-corrosion)
- Housing certification label intact and legible (Class/Division/Group or ATEX marking visible)
- No unauthorized modifications visible (drilled holes, welded attachments, paint over flame paths)
Window Condition
- Window glass free of cracks, chips, or deep scratches
- Window seal appears intact (no visible gap between glass and housing)
- Window surface clean enough for camera imaging (or wiper system operational)
Cable Entries
- All cable glands tight with no visible movement when firm hand pressure applied
- No cable damage visible at gland entry points
- Blanking plugs present and tight on all unused entries
- No corrosion at gland bodies (particularly for metallic glands in corrosive environments)
Mounting and Structure
- Camera mounting bracket secure — no movement when hand pressure applied
- Conduit entries secure and sealed (no movement, no visible gap at sealing fittings)
- Camera aimed at intended coverage area (no drift from original position)
- Wiper/washer system operational if installed
Function Check
- Camera image visible in VMS — no offline status
- Image quality acceptable — no fogging, streaking, or focus degradation
- Night vision / IR illumination functional (if applicable)
- PTZ functions responsive if applicable
Annual Close Inspection Checklist
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Includes all quarterly checks plus the following:
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
Fastener Verification
- All housing cover bolts present and at specified torque (per manufacturer datasheet)
- No bolts replaced with non-equivalent hardware (wrong grade, wrong thread pitch, wrong material)
- Spring-lock washers or equivalent locking mechanism intact on cover bolts
Cable Gland Detail Check
- Cable glands at correct torque per manufacturer specification
- Cable outer jacket undamaged at point of gland compression
- Cable outer jacket minimum bending radius maintained at gland exit
- Cable gland certification marking visible and matching required classification
External Flame Path Check (without opening)
- Cover-to-housing mating surface free of visible damage, deep scratches, or corrosion on accessible surfaces
- No paint, sealant, or other material applied to flame path surfaces (a common non-compliance from well-meaning maintenance teams)
- External seals (where applicable on Ex e areas of the housing) intact and pliable — no cracking or compression set visible at edges
Conduit and Sealing Fitting Check
- Sealing fittings within 18 inches of housing (NEC requirement) filled — compound level visible through inspection port if accessible
- No moisture ingress visible at conduit entrances
- Conduit support hangers intact — no drooping that would stress conduit entry
3–5 Year Detailed Inspection Checklist
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Requires hot-work permit or confirmed area isolation before opening in classified area.
Flame Path Verification
- Flame path gap width measured with feeler gauges at multiple points around cover mating surface
- Measured gap width within certified specification (from equipment certificate or manufacturer datasheet)
- Flame path surface condition: no deep scratches crossing the full path length, no corrosion pitting greater than 50% of flame path length
- Window frame-to-housing flame path verified (separate from cover flame path)
Internal Component Check
- No water or condensation inside housing
- No evidence of overheating — discolored components, melted insulation, or burn marks
- All internal cable connections tight
- Camera model visible on internal label matches model listed on housing certificate
- No unauthorized modifications to internal wiring or components
Seal and Gasket Check
- Window gasket (if applicable) replaced if hardened, cracked, or showing compression set
- Cable gland seals replaced per manufacturer service interval
- Anti-condensation heater (if installed) functional
Post-Incident Inspection
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Following any fire, explosion, significant impact, flooding, or chemical spill in the classified area, perform an immediate inspection before returning cameras to service:
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
- Check for external signs of fire exposure — heat discoloration, melting, soot deposits on flame path areas
- Check for impact damage — deformation, cracked window, damaged cable glands
- Check for flooding — water ingress to enclosure, corrosion initiation
- If any compromise found, remove from service and have inspected by certified ex-equipment specialist before returning
- Document the incident, inspection findings, and any equipment removed from service
Maintenance Documentation Requirements
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. For each camera in a classified area, maintain a record containing:
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
- Camera make, model, and serial number
- Housing make, model, and certification number
- Installation location and area classification drawing reference
- Date of installation and installer qualification
- Complete inspection log with date, inspector name, inspection type, findings, and actions taken
- Records of any repairs, part replacements, or modifications (with certification verification for replaced parts)
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. IEC 60079-17 recommends keeping inspection records for the life of the installation. For process safety purposes, a minimum of 10 years or the length of the major equipment inspection cycle (whichever is longer) is generally considered adequate.
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
What Invalidates the Certification
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. The following actions immediately invalidate an explosion-proof camera’s certification and create a non-compliant installation:
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
- Drilling or machining the housing for any purpose
- Welding anything to the housing
- Replacing cover bolts with non-equivalent hardware (wrong grade, length, or material)
- Applying paint, sealant, or coating to flame path mating surfaces
- Installing a different camera model than specified in the certificate
- Using a non-certified cable gland or conduit fitting at any housing entry
- Removing and reusing a sealing fitting compound
Frequently Asked Questions
How often should explosion-proof cameras be inspected?
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. A visual inspection should be performed quarterly and a close inspection annually at minimum. A detailed inspection every 3–5 years is standard practice. After any incident — fire, explosion, impact, or flooding — an immediate inspection is required before the camera is returned to service. IEC 60079-17 provides the governing framework.
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
What is the difference between a visual, close, and detailed inspection?
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. A visual inspection checks for obvious external damage without opening the equipment. A close inspection involves thorough external examination including fastener torques and cable gland conditions. A detailed inspection requires opening the enclosure to inspect internal components and verify flame path dimensions — this requires a hot-work permit or area isolation in a live classified area.
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
Can I open an explosion-proof camera enclosure in a live hazardous area?
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Generally no — opening an explosion-proof (Ex d) enclosure in a live classified area requires a hot-work permit and typically area isolation. Some facilities allow opening Ex e enclosures under specific conditions. Check your facility’s hot-work and maintenance procedures. Never open a live Ex d enclosure in a classified area without proper authorization.
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
What invalidates an explosion-proof camera’s certification?
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Drilling holes in the housing, welding attachments, replacing fasteners with non-equivalent hardware, using non-certified cable glands, installing an uncertified camera in a certified housing, painting over flame paths, and impact damage that alters flame path dimensions all invalidate the certification. Any of these require re-certification or equipment replacement.
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
How do I verify the flame path is still in specification?
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Flame path verification requires measuring gap width and length with precision gauges and comparing against the certificate specifications. Visual inspection alone cannot verify flame path dimensions. If gaps exceed the certified maximum, the enclosure must be replaced or refurbished by an authorized service center.
For definitions of key hazardous area terms used in this guide, see the Hazardous Area Classification Glossary.
Further Resources
A documented explosion-proof camera maintenance checklist is required to verify that certified assemblies remain compliant between formal inspection intervals. Browse Veilux’s range of explosion-proof cameras and explosion-proof housings certified for hazardous areas. For regulatory reference, see NFPA 70E electrical safety standard and OSHA Process Safety Management.
For a complete overview of all selection criteria, see the Explosion-Proof Camera Selection Guide: Complete Hub.