Quick Answer
To specify explosion-proof lighting for a chemical storage facility, start with the site’s official area classification report to identify Zone 0, 1, 2, or dust Zones 20, 21, 22. Match each zone to the correct protection concept, Ex d, Ex e, Ex m or Ex tb, and select IECEx or ATEX certified fixtures rated for the gas group and temperature class present. Confirm IP67 minimum ingress protection, set lux and mounting requirements per area, then document certification and installation records at handover for ongoing compliance and inspection.
This guide is written for safety managers, electrical engineers and procurement teams responsible for specifying lighting on a chemical storage facility, whether that is a tank farm, drum store, fuel terminal or packaged chemical warehouse. The scope here is limited to chemical storage specifically, since the gas and dust groups present, and therefore the correct explosion-proof lighting, differ from mining or oil and gas processing sites.
Specifying explosion-proof lighting correctly is a zone-by-zone exercise, not a single product decision. Get the zone wrong, or apply a general purpose hazardous location lighting product across the whole site, and you either create a compliance gap or pay for protection levels the site does not need. MineGlow’s explosion-proof lighting range and hazardous LED lighting products are built around exactly this zone-specific approach, so the process below reflects how a specification should actually come together.
Step 1: Assess Site Classification and the Zone System
Every specification starts with the facility’s official area classification report, prepared by a competent person as part of the site’s hazardous area assessment. This document marks Zone 0, Zone 1 and Zone 2 for gas and vapour risk, or Zone 20, Zone 21 and Zone 22 for combustible dust, directly onto the site drawings. Zone 0 covers areas where an explosive atmosphere is present continuously, Zone 1 covers areas where it occurs occasionally during normal operation, and Zone 2 covers areas where it is only likely under abnormal conditions.
Alongside the zone, record the gas or dust group and temperature class, or T-code, for each area, plus ambient temperature range and corrosion category. Temperature class ratings run from T1 at 450 degrees Celsius maximum surface temperature down to T6 at 85 degrees Celsius, and this figure has to sit below the ignition temperature of whatever chemical is stored in that zone. Skipping this step and guessing at classification is the single most common reason a lighting specification fails inspection later.
Step 2: Map Zones to Protection Concepts and Fixture Types
Once the zones are confirmed, each one needs a specific protection concept assigned to it. Ex d, flameproof enclosure, contains any internal explosion within the fitting itself. Ex e, increased safety, prevents sparking or excessive heat under normal operating conditions. Ex m encapsulates components in a protective compound, and Ex tb is the protection concept used specifically for combustible dust zones. In the IEC and ATEX system, each of these corresponds to an Equipment Protection Level that must match the zone’s risk classification.
For gas zones, acceptable LED lighting fixtures need a protection concept rated for that specific zone, not just a general hazardous area marking. Zone 0 requires the highest protection level, typically Ex ia or Ex ma, while Zone 2 has more flexibility and can often use Ex nA rated equipment as well as Ex d or Ex e fixtures. Dust zones need dust-tight, Ex tb rated fixtures regardless of gas classification, since dust ignition behaves differently to gas ignition.
Step 3: Set Fixture Performance Requirements
With protection concepts assigned, define the actual lighting performance needed in each area. Set lux targets for storage aisles, walkways and loading areas based on the tasks carried out there, and choose a correlated colour temperature that supports safe visual tasks, typically a cooler white for inspection and loading areas. Determine beam angle and mounting height together, since a fixture mounted too high with too narrow a beam leaves dark patches between racking or tanks.
Anti-corrosion housing and a minimum IP67 ingress protection rating should be treated as non-negotiable for chemical storage, since many stored chemicals are corrosive as well as flammable, and standard IP66 rated fixtures do not offer the same protection against liquid ingress during washdown or spill events.
Step 4: Select Certified Hazardous LED Lighting
Certification is where a specification either holds up or fails. Every fixture needs IECEx, ATEX, or NEC marking that matches the actual zone it is installed in, not a general hazardous area claim on the datasheet. Request full test reports and certificate numbers for each fixture, and verify compliance against the IEC 60079 series, which underpins both the ATEX and IECEx certification systems. In North America, explosion-proof lighting instead needs to meet UL 844 requirements under the NEC framework.
Confirm the IK impact rating alongside ingress protection, since chemical storage areas often involve forklift traffic and stacked drums where mechanical impact risk is real. You can verify a certificate’s authenticity directly through the IECEx official certification register, which is worth doing before any product is added to a tender document.
Step 5: Compare Product Options
When comparing suppliers, request the full datasheet for the specific product line, such as MineGlow’s SafeGlo IECEx range for Ex zone applications, alongside comparable datasheets from alternative suppliers. Compare luminous efficacy and driver thermal ratings, since heat management inside a sealed explosion-proof housing directly affects fixture lifespan. Warranty terms and repair kit availability also matter more here than in general industrial lighting, since replacing a fixture in a live hazardous zone is a bigger job than a standard maintenance callout.
Step 6: Plan Installation, Wiring and Mounting
Wiring in hazardous locations needs certified conduit glands and explosion-proof junction boxes, sealed according to the specific certification requirements for that zone. Define mounting brackets and mechanical supports that suit the corrosion category identified in Step 1, and plan cable routing to avoid mechanical damage from forklift traffic and chemical exposure from spills or washdown. Ventilation systems on site can also change a zone’s classification, so installation planning should account for how ventilation performance affects the area being wired.
Step 7: Address Combustible Dust Zones Separately
Dust zones 20, 21 and 22 need their own pass through the specification, since dust behaves differently to gas. Select dust-tight, Ex tb rated fixtures with smooth, dust trap-free surfaces, and confirm the fixture’s surface temperature stays below the dust cloud and dust layer ignition temperatures relevant to the material stored, since metal dusts and organic dusts ignite at different thresholds. Plan cleaning access and dust control procedures alongside the lighting specification, since a fixture that cannot be cleaned without disturbing accumulated dust creates an ongoing risk regardless of its certification.
Step 8: Specify Emergency Lighting and Escape Systems
Escape routes through or past classified zones need their own emergency lighting specification, including minimum duration and lux levels appropriate to the egress path. MineGlow’s em-Control emergency lighting system integrates directly with hazardous area lighting where required, with a designated emergency power feed and monitoring circuit. Functional testing procedures for emergency modes should be written into the specification from the start, not added after commissioning.
Building the Zone by Zone Specification Matrix
The most practical way to bring all of this together for a tender document is a matrix with one row per zone, listing the required fixture type, protection concept, certification, IP and IK ratings, T-code and mounting height for that area. This turns the specification into something a procurement team can send to multiple suppliers for like-for-like comparison, and something an inspector can check installed fixtures against later. Our detailed breakdown on what to look for in hazardous area LED lighting certifications and testing reports is a useful reference when building this matrix, since it covers exactly what documentation to request from a supplier at this stage.
Include factory test reports, conformity documents and installation method statements in the purchase order itself, and instruct the supplier to provide marking and operation manuals with delivery. Estimate ongoing maintenance costs at this stage too. LED explosion-proof fixtures typically run 90 percent more efficiently than traditional lighting and can reduce maintenance frequency by up to 70 percent, which changes the total cost of ownership calculation significantly compared with older technology.
Commissioning and Handover
At commissioning, witness final inspection and functional testing on site, and verify that the markings on each installed fixture match the certificate scope specified in the tender. Update as-built drawings and operation and maintenance manuals to reflect what was actually installed, and hand over full certification packs and maintenance schedules to the site’s safety and health management system. Annual inspections are the standard requirement for explosion-proof lighting going forward, with quarterly checks on electrical connections and monthly visual inspections of fixture enclosures recommended as good practice.
Why MineGlow for Chemical Storage Facility Lighting
The SafeGlo hazardous LED lighting products are built specifically around this zone-by-zone specification process, with IECEx and ATEX certification, IP67 minimum ingress protection and full test documentation available for every fixture. Our team can help you work through classification, protection concept selection and the specification matrix for your chemical storage facility before it goes to tender.
Contact MineGlow today to discuss certified explosion-proof lighting for your site.
Frequently Asked Questions
Q: What is the first step in specifying explosion-proof lighting for a chemical storage facility?
The first step is obtaining the site’s official area classification report, which identifies Zone 0, 1, 2 or dust Zones 20, 21, 22 for each part of the facility. Lighting selection cannot happen correctly until this classification exists.
Q: What is the difference between Ex d and Ex e protection concepts?
Ex d, flameproof enclosure, contains any internal explosion within the fitting so it cannot ignite the surrounding atmosphere. Ex e, increased safety, is built to prevent sparking or excessive heat occurring in the first place under normal operating conditions.
Q: What ingress protection rating do chemical storage facilities need?
IP67 is the standard minimum for chemical storage areas, protecting against dust ingress and temporary liquid immersion. This is important because many stored chemicals are corrosive as well as flammable, and washdown or spill events are common.
Q: Do combustible dust zones need different lighting to gas zones?
Yes. Dust zones 20, 21 and 22 require Ex tb rated, dust tight fixtures with smooth surfaces free of dust traps, and the fixture’s surface temperature must stay below the specific ignition temperature of the dust present, which differs from gas ignition thresholds.
Q: How often does explosion-proof lighting need to be inspected?
Annual inspections are the standard compliance requirement. Good practice also includes quarterly checks on electrical connections and monthly visual inspections of fixture enclosures to catch corrosion or damage before it becomes a compliance issue.