Industrial Floor Maintenance Guide: Inspection of Epoxy Resin Coatings, Expansion Joints and Drainage Systems

1. Scope & Purpose

This technical maintenance manual is intended for the systematic inspection and maintenance of industrial floors with a focus on epoxy resin coatings, expansion joints and integrated drainage systems in production and storage areas. It is aimed at qualified maintenance technicians and maintenance personnel in manufacturing companies, in accordance with the requirements of DIN 18560 (screeds in construction) and the recommendations of VDI 6000 sheet 4 (maintenance of floors). The aim is to ensure the durability, functionality and safety of the floor structure. Regular implementation of these maintenance measures is critical for avoiding production downtimes, maintaining hygienic standards and protecting employees from slipping and tripping hazards. These instructions are intended for periodic maintenance, typically every six months or in the event of visible damage or functional limitations.

2. Safety precautions

Before starting any work on industrial floors, strict safety measures must be observed to protect personnel and equipment. Compliance with the workplace safety regulations in accordance with DGUV rule 112-192 (use of personal protective equipment for foot protection) and DGUV rule 112-195 (use of personal protective equipment for head protection) is mandatory.

DANGER:

• Secure the work area: Mark the work area with barrier tape, warning signs and, if necessary, warning posts. Access by unauthorized personnel must be prevented.
• Personal protective equipment (PPE): It is mandatory to wear safety shoes (protection class S3 according to EN ISO 20345), chemical-resistant protective gloves (according to EN 374, especially when handling cleaning or repair agents), safety glasses (according to EN 166) and when dust is generated or the use of solvents, respiratory masks (FFP2/FFP3 according to EN 149).
• Lockout/Tagout (LOTO): When cleaning work on drainage systems that are connected to electric pumps or other machine parts, these must be switched off in accordance with the operational LOTO procedures (according to EN 1037) and secured against being switched on again.
• Danger of slipping: Spilled liquids, cleaning or repair products can be extremely slippery. Clean and secure areas immediately. Use suitable non-slip pads or shoes.
• Chemicals: Repair resins, hardeners and cleaning solutions can be skin irritating, corrosive or flammable. Safety data sheets (SDS) must be consulted. Ensure adequate ventilation. Keep ignition sources away.
• Fall hazard: Uneven surfaces, open drainage or loose covers pose tripping hazards. Check before entering the area.
• Lifting equipment: When removing heavy gratings or covers, use suitable lifting equipment or several people to avoid back injuries.

3. Required Tools & Materials

4. Pre-inspection checklist

This checklist must be completed before detailed maintenance begins in order to obtain an initial overview of the condition of the industrial floor and to identify potential sources of danger.

5. Step-by-step instructions

1. 5.1 Preparation of the work area

   Action: Completely clear the area to be serviced of machines, materials and personnel. Install barriers and warning signs in accordance with ASR A1.3. Ensure adequate lighting and ventilation. Put on PPE.

   Specific values: Safety distance to machines min. 1.5 m. Illuminance min. 500 lux.

   Visual indicators: Area clearly demarcated, warnings clearly visible, sufficient light.

   Common errors: Insufficient security of the area leads to unauthorized access and danger.

2. 5.2 Inspection of epoxy resin coating

   Action: Check the floor systematically, section by section, for damage. Shine an inspection lamp diagonally over the surface to make unevenness and small cracks more visible.

   1. 5.2.1 Visual inspection for surface defects

      Action: Inspect the entire surface for cracks, chips, blistering, craters, discoloration, chemical attack, and signs of abrasion. Areas under machines, in driveways and near wet areas are particularly critical.

      Specific values: Cracks up to 0.2 mm wide are often not critical, wider cracks or cracks with loss of substance require measures. Spalling areas > 10 cm² or > 2 mm deep must be documented.

      Visual indicators: Intact coating shows a uniform, continuous surface without visible damage.

      Common mistakes: Overlooking small damages that can quickly develop into larger problems.

   2. 5.2.2 Coating thickness measurement (if required)

      Action: Measure the layer thickness of the epoxy resin coating at representative points using a layer thickness measuring device (eddy current or magneto-inductive method). Calibrate before measurement.

      Specific values: Typical layer thicknesses vary from 2 mm to 5 mm for heavy-duty industrial floors. Deviations of more than 20% from the target thickness are critical.

      Visual Indicators: Consistent readings across the entire range.

      Common errors: Insufficient calibration of the measuring device or measuring on contaminated/damaged surfaces.

   3. 5.2.3 Adhesion test (optional, if required)

      Action: If delamination or insufficient adhesion is suspected, carry out an adhesion test according to EN ISO 4624 (pull-off test). A test stamp is glued to the surface and removed vertically with a testing device. The breaking point and the tensile force are documented.

      Specific values: An adhesive tensile strength of > 1.5 N/mm² is typical and required for industrial floors. Values ​​below this indicate liability problems.

      Visual indicators: Fracture in the coating itself (cohesive fracture) is ideal; Fracture at the interface to the substrate (adhesive fracture) is a sign of inadequate adhesion.

      Common errors: Insufficient preparation of the test surface or uneven application of the test stamp.

3. 5.3 Inspection of expansion joints

   Action: Systematically check all expansion joints for damage and functionality.

   1. 5.3.1 Visual inspection of the joint material

      Action: Check the entire length of each joint for cracks, brittleness, separation from the edge of the joint, missing material and entry of dirt. Pay particular attention to areas with high mechanical stress (e.g. forklift traffic).

      Specific values: Cracks in the joint material > 1 mm wide or > 5 mm deep require repair. Detachments longer than 5 cm require renovation.

      Visual indicators: Joint material is elastic, continuous and adheres fully to both flanks. No visible cracks or crevices.

      Common errors: Only check the surface of the joint without taking the side flanks into account.

   2. 5.3.2 Measuring the joint width and depth

      Action: Measure the width at several points along the joint using a tape measure or feeler gauge and assess the depth (if visible). Check whether there is backfill material.

      Specific values: Typical joint widths are between 10 mm and 25 mm. Larger width deviations within a joint (> ±5 mm) or insufficient depth for the sealant (< 10 mm) can cause functional problems. The backfill material should be approximately 1/3 of the joint width below the surface.

      Visual indicators: Uniform joint width, correctly positioned backfill material.

      Common mistakes: Neglecting the depth, which is crucial for the correct function of the joint sealant.

4. 5.4 Testing the drainage systems

   Action: Inspect all floor drains, gutters and gullies.

   1. 5.4.1 Visual inspection and functional check

      Action: Remove gratings or covers. Check the area below for contamination, deposits, corrosion and structural damage. Check whether the gratings are flush with the floor surface and rest securely. Pay attention to the formation of odors (indication of standing water or blockages).

      Specific values: Gratings must have a load class according to EN 124 that is suitable for traffic in the area. Unevenness of > 3 mm at the transition to the floor is not permitted.

      Visual indicators: Drainage elements are clean, free of deposits, corrosion and damage. Gratings are firmly in place.

      Common errors: Superficial inspection without removing the covers, which means deeper blockages are missed.

   2. 5.4.2 Flow test

      Action: Pour a defined amount of water (e.g. 20 liters) into the drain or gutter and measure the time for the drain. Comparison with reference values ​​or neighboring, intact systems.

      Specific values: A drain time of more than 30 seconds for 20 liters of water indicates an incipient blockage and requires cleaning. The target flow can be found in the system plan.

      Visual indicators: Water drains quickly and without leaving any residue.

      Common errors: No quantitative measurement of flow, only subjective assessment.

5. 5.5 Measures if defects are identified (repair)

   Action: Correct identified defects according to the following instructions. Priority is given to safety relevance and the progress of the damage.

   1. 5.5.1 Repair of coating damage

      Action: Remove loose or delaminated areas of the epoxy resin coating mechanically (milling, sanding) until a solid surface is achieved. Cut edges cleanly. Thoroughly clean, degrease and vacuum the surface. Mix the epoxy resin repair mortar according to the manufacturer's instructions (typically component A to B in a ratio of 2:1 by weight) and apply quickly. Remove the surface flush with the existing coating using a smoothing spatula. Strictly adhere to the curing times.

      Specific values: Repair areas must be free of dust and grease. The layer thickness of the repair mortar corresponds to the original coating (e.g. 2-3 mm). Curing time for walkability: 12-24 hours at 20°C. Complete chemical resistance after 7 days.

      Visual indicators: Repaired area is smooth, flush and color matches the surrounding area. No transition is noticeable.

      Common errors: Insufficient preparation of the substrate, incorrect mixing ratio or processing too quickly without adhering to the pot life.

   2. 5.5.2 Renovation of expansion joints

      Action: Completely remove the old, damaged joint material. Clean the joint edges mechanically (flex, brush) and vacuum to create a clean, adhesive surface. If necessary, apply primer according to the manufacturer's instructions and allow to flash off. Insert the backfill material (round cord) so that it ensures the correct cross-section of the joint sealant (ideal width-to-depth ratio approx. 2:1, min. 1:1). Apply the new PU joint sealant without bubbles and evenly with a joint gun and remove it with a smoothing tool.

      Specific values: Joint flanks must be dry (max. 4% residual moisture), free of dust and grease. Curing of the joint sealant: approx. 2-3 mm per 24 hours at 23°C and 50% relative humidity. Shore A hardness of the sealant after curing 25-35.

      Visual indicators: The joint is completely filled with sealant without bubbles. The sealant adheres cleanly to both flanks.

      Common errors: Insufficient cleaning of the joint flanks, missing backfill material, which leads to three-sided adhesion and cracking.

   3. 5.5.3 Cleaning and repair of drainage systems

      Action: Remove gratings and covers and clean them separately. Manually remove coarse deposits and dirt from the gutters and drains. Then rinse and vacuum thoroughly with a high-pressure cleaner (min. 120 bar) using an alkaline industrial cleaner (e.g. pH 10). If there is corrosion on metal parts, clean them, remove rust if necessary and treat with corrosion protection (e.g. zinc dust paint). Repair damaged gutters or gullies (cracks, breaks) with suitable concrete or repair mortar. Reinstall the gratings.

      Specific values: Flushing pressure 80-150 bar. Water temperature max. 60°C. Repair mortar must be frost and chemical resistant. Torque for grating screws (if available) according to manufacturer's instructions, typically 20-30 Nm.

      Visual indicators: Gutters and drains are completely clean and free of blockages. Water flows away unhindered. Gratings are secure and flush.

      Common mistakes: Only superficial cleaning, so new blockages quickly form again.

6. Post-Maintenance Verification Checklist

After all maintenance and repair work has been completed, this checklist must be used to ensure the quality of the measures carried out.

7. Troubleshooting

This section provides assistance with common problems after or during maintenance.

8. Recommended maintenance schedule

A structured maintenance plan is crucial for the longevity and functionality of industrial floors.

9. Spare parts reference

Selecting the right replacement parts and materials is critical for the long-term repair of industrial floors. UNITEC-D offers a wide range of high-quality components.

For detailed information and ordering spare parts, please visit the UNITEC-D e-catalog: https://www.unitecd.com/e-catalog/

10. References

• DIN EN 13813: Screed mortar, screed compounds and screeds - properties and requirements
• DIN 18560: Screeds in construction - parts 1-7
• VDI 6000 Sheet 4: Equipment of and with buildings - floors in work rooms - design, selection, maintenance
• EN ISO 20345: Personal protective equipment - safety shoes
• EN 374: Protective gloves against dangerous chemicals and microorganisms
• EN 166: Personal eye protection requirements
• EN 149: Respiratory protective devices - Filtering half masks for protection against particles - Requirements, testing, labeling
• EN ISO 4624: Coating materials - tear test to determine adhesion strength
• EN 124: Attachments and covers for traffic areas - components made of cast iron, steel, reinforced concrete and aluminum
• Manufacturer documentation and safety data sheets (SDS) of the coating and repair materials used.
• BGR 181 (DGUV Rule 108-003): Floors in work rooms and work areas with a risk of slipping.
• ATEX Directive 2014/34/EU (if applicable for potentially explosive atmospheres).