wpis 10

Industrial Floorings Part 2

As the flooring is used, the damage to the top layer of the finish is revealed which is not only the result of being made incorrectly, but is also the result of the missing specification of some parameters at the design stage.

The Most Common Damage

As far as surface hardened industrial floorings are concerned, it is worth to know what errors occur most often at the construction stage.

Dusting, Excessive Abrasion (Photo1]

Factors that affect excessive dusting and abrasion are: uneven distribution of the hardening layer or insufficient amount of dispensed dry-shake material. The reason for the problems may also be the impeded dry-shake process of concrete structure penetration resulting from trowelling that may have been made too late and the process of flooring care that may have been made incorrectly or may not have been made at all.

Photo 1. Hardening Layer Distributed Unevenly

Scratches and Cracks (Photo 2]

There are many reasons for scratches and cracks in the flooring. Defects of this type make its aesthetics deteriorated and are directly related to its functionality and durability. Most often, scratches occur due to concrete shrinkage stresses in the early phase of paving the flooring. This is often because it is inadequately cared for, too shallow dilatation cuts were made at the wrong time or no cuts were made at all. In addition, there are soil settlements phenomena under the flooring or the supporting structure of the flooring is excessively loaded.

Photo 2. Flooring Scratch and Cracks.

Grid Of Micro-Cracks And Micro-Scratches [Photo 3]

Most commonly, micro scratches are caused by excessive flooring drying, too much dry-shake or other technological factors acting during the flooring trowelling and hardening.

Photo 3. Grid of Surface Micro-Scratches on the Flooring

Chips Caused by Frost Corrosion of Aggregate [Photo 4]

Most commonly, chips of this type occur because aggregate in the concrete mixture formula were improperly selected or because dry-shake aggregate were low quality in relation to the prevailing climatic conditions. These defects are strictly related to the lack of resistance of aggregate grains to transfer the volume changes caused by unstable physical conditions, such as freezing-thawing or alternate dampening and drying. This type of Damage is quite often found in multi-level garage parking lots (e.g. in shopping centres), which have canopies, but because of moving cars and washing are permanently moistened.

Photo 4. Flooring Chips Caused by Frost Corrosion of Aggregate

Chips Caused by the Alkaline Reaction of the Concrete Aggregate with Cement [Photo 5]

The damage is the result of the harmful reactions of active silica obtained from the aggregate with alkali contained in the cement. Most commonly, alkali-reactive aggregate are grains of porous limestones, gaizes (containing amorphous silica), flints, chalcedony, hornstones, tridymite, cherts and lidites. The reactions of reactive silica with cement alkali start with the aggression of hydroxides obtained from the alkalis of cement to the silica minerals of the aggregate. An alkaline-silica gel, which is a compound capable of absorbing large amounts of water, is then created, thus increasing its volume. The swelling product obtained causes internal pressure. As a result, cracks are created; the surrounding hydrated cement grout breaks and is destroyed. These processes only occur with water. The minimum relative humidity inside the concrete that lets these reactions happen is approx. 85% at 20°C. The tests have shown that the alkali – silica reaction is the fastest in the temperature range of 10-36°C. The intensity of this type of reaction depends to a large extent on the size of the grains and their porosity. If cement is the only source of alkali, then their concentration will depend on the size of the reactive surface of the aggregate grain. Flooring destruction is manifested as craters of up to 3 cm deep, in the form of so-called pop-outs. However, the occurrence of reactive alkali aggregates in concrete causes large surface damage and has a much greater impact on the reduction of the surface durability. The only way to stop the alkali – silica reaction is to dry the concrete and cut it off from the impact of moisture.

Photo5. Flooring Chips Caused by the Alkaline Reaction of the Concrete Aggregate with Cement

Chips Caused by the Alkaline Reaction of the Dry-Shake Aggregate with Cement [Photo 6]

As it is with the alkaline reactions of the concrete aggregates of a constructional slab with cement, the use of alkaline reactive aggregate (AAR aggregate grains of both ASR silica and ACR carbonate) in the dry-shake may make them react with the cement alkali. As the adhesion of aggregate grains with the hydrated cement grout weakens, individual grains gradually chip away from the surface from the usable flooring surface.

Photo 6. Flooring Chips Caused by the Alkaline Reaction of the Dry-Shake Aggregate with Cement

Chipping Away Grains of the Dry-Shake

The pattern of the chip formation in the flooring is related to the projecting part of the grains above the surface of the flooring and its loosening under the influence of friction of the usable motion [traffic, pedestrians]. Grains, which are moved in cycles, loose and chip from the flooring. This mechanism is a result of grains being not properly fixed in, in most of the cases, the fine aggregate.

Protruding Reinforcement Fibres Scattered on the Surface [Photo 7)

 The increased amount of steel fibres released from the dispersed reinforcement from the flooring slab can have many causes. One of the main reasons is the excessive trowelling. A frequent reason for defects is also the phenomenon of so-called bleeding [releasing water onto the surface of the concrete) while making the construction panel, making it difficult to shape and trowel the flooring. Increased amount of water in the near-surface layer of the flooring makes the concrete structure locally weakened, reducing its surface strength and durability through its excessive abrasion as it is used.

Photo 7. Steel Fibres on the Surface of the Floor.

Degraded Concrete Surface Caused by Frost Corrosion [Photo 8)

Heavy frost corrosion or frost corrosion caused by the presence of de-icing salts on the entire surface of the flooring is most often found in floorings exposed to direct atmospheric factors, i.e. located outdoor, in unprotected areas. This is usually caused by failing to adjust the concrete parameters to the prevailing environmental conditions and the making the construction board of concrete that is not resistant to frost in the presence of de-icing salts.

Photo 8. The Surface Structure of Concrete Degraded by Frost Corrosion.

Damage to the Surface due to Acidic Corrosion [Photo 9)

In food production industrial plants, the phenomena of acid corrosion resulting mainly from decomposition of calcium carbonate by acids and leaching erosion as a result of the impact of washing devices can often be found. Mineral surfaces, unlike resin ones, are absorbent. When exposed to chemicals, they do not fully protect against aggressive chemical environment.

Photo 9. The Surface Structure of Concrete Degraded by Acid Corrosion

Dry-Shake Top Layer Scaling (Delamination) [Photo 10)

Making industrial floorings in extreme weather conditions often causes many problems with the surface layer scaling. This phenomenon is called horizontal delamination. This is usually resulting from trowelling that may have been begun too late or too early. In addition, water that may have been released as a result of excessive air temperature, too much air flow and insufficient care may affect the scaling. Flooring scaling may reach even 2 cm deep into the surface layer.

Photo 10. Flooring Scaling Caused by Poor Care at Too High Temperatures

Excessive Abrasibility [Photo 11]

In large-area logistics warehouses, industrial plants or motor vehicle diagnostic stations, since they are heavily used or heavily loaded, the hardening material may be excessively scaled where the vehicles pass. Damage may be the result of wrong selection of the hardening dry-shake with insufficient durability parameters in the prevailing conditions. They are often the result of the wrong care or too small amount of the dry-shake rubbed in.

Photo 11. Intensively Worn Surface in a Bus Depot.

Recapitulation

Industrial floorings with surfaces hardened by the so-called dry-shake are the most popular method of making the finishing layer used nowadays in service and industrial construction industry. At the design stage, physicochemical parameters are often not specified as far as the requirements for floorings are concerned. Most commonly, the designers describe only the strength parameters of concrete in terms of structural layer load. In the design recommendations, often no requirements for the top layer of the flooring are specified or their description is vague. These deficiencies in the designs are the result of failing to properly match the floorings to the real environmental and operational conditions.

Industrial floorings with surfaces hardened by the so-called dry-shake are the most popular method of making the finishing layer used nowadays in service and industrial construction industry. At the design stage, physicochemical parameters are often not specified as far as the requirements for floorings are concerned. Most commonly, the designers describe only the strength parameters of concrete in terms of structural layer load. In the design recommendations, often no requirements for the top layer of the flooring are specified or their description is vague. These deficiencies in the designs are the result of failing to properly match the floorings to the real environmental and operational conditions.

Drawn up by:

Karol Sadłowski, M.Sc.

Damian Urbanowicz, M.Sc.

Maciej Warzocha, M.Sc.

  1. PN-EN 13318:2002 Floor screeds and materials to make them. Terminology.
  2. AGI 302. 1R-04; ACI Committee 302, Guide for Concrete Floor and Sfab Construction. America Concrete Institute, 2004.
  3. Bautech Sp. z o.o., Product Data Sheets.
  4. PN-EN 206:2014-04 Concrete. Requirements, Properties, Production and Compliance.
  5. W. Ryżyński, Concrete Floor Surface Hardening, “Construction Engineer”, No. 4/2015.
  6. B. Chmielewska, G. Adamczewski, Defects and Repairs of Industrial Surface Hardened Floorings, Materials of the XXVI Scientific and Technical Conference “Construction Failures”, 2013.
  7. H. Rainer Sasse, Design and Performance Requirements, “Industrial floors” Scientific and Technical Seminar, 2007.
  8. A. Szydło, Road Surfaces Made of Cement Concrete, Polski Cement Sp. z o.o., 2004.
  9. IBDiM, GDDP, Catalogue of Typical Rigid Surface Constructions. War­szawa 2001.
  10. DIN 18202 Toleranzen im Hochbau – Bauwerke Tabelle 3.
  11. PN-EN 12620+A1:2010 Aggregate for Concrete.
wpis 09

Industrial Floorings Part 1

I. Types of Floorings

The definition of the flooring is specified in PN- -EN 13318 Standard [1], which introduces definitions for floor screeds. According to the standard, the flooring is the top, usable floor layer. It should be understood as the surface of the structural system on which pedestrian traffic and the movement of vehicles takes place, on which the devices are placed and materials are stored. The construction layer of the floor and the foundation system are responsible for the possibility of transferring the live loads and providing adequate thermal, acoustic or anti-water insulation, while the task of the top layer of the entire structural system is to provide appropriate performance and durability characteristics. At the design stage it should be remembered that it is primarily the flooring that makes the entire system durable, protects the lower layers of the system against aggressive environmental factors and makes the entire system safe to use. The industrial floors can be basically divided according to the existing loads. According to the classification adopted by the ACi [2] Committee, four classes of loads have been defined from the light loads [for wheel loads up to 10 kN] to very heavy loads (for wheel loads above 80 kN).

However, as far as the finishing layer of the floor is concerned, other criteria of the division than the requirements of the load-bearing capacity of the structure itself should be adopted. While designing, such parameters as: usage environmental conditions (room humidity, temperature, temperature amplitude, frost factors), abrasion resistance (transit frequency, type of traveling vehicles, washing frequency, type of washing machines or cleaning products), resistance to chemical aggression (type of cleaning agents, type of products used on the flooring or stored on it) should also be taken into account. This is a large group of parameters that the future flooring user should define as design guidelines.

Taking into account the factors mentioned above, the designer selects the technology for making the flooring. Based on the technology and the type of material, industrial floors can be divided into: surface hardened concrete flooring (DST – dry shake topping); resin flooring: polypropylene, polyurethane; thin‐layer, self‐spread decorative flooring; finished with ceramic cladding or roughly plastered.

 II. Basic Requirements

For economic reasons (in theory, the smallest performance requirements), in industrial and service facilities in Poland, surface hardened floorings, the so-called DST, using dry shake topping method are the most commonly made. If the technology is properly used, this is a technology that allows to achieve high abrasion resistance, dusting and increased hardness. However, if the appropriate technological regime is not observed and when the floor is made in unfavourable weather conditions, numerous damages occur even in the first year of use of the flooring.

According to the generally accepted principles of designing concrete mixes for floorings, cement mass must not exceed 350 kg/m3, and the w/c ratio must not exceed 0.5. The sufficient content of the aggregate fraction below 0.2 mm is particularly important. The content of this fraction should not be less than 4%. At the same time, the content of dust [cement + aggregate less than 0.125 mm] should be limited to 400 kg/m3, and the content of cement + aggregate fraction lower than 0.25 mm should be limited to 500 kg/m3. In the case of dry-shakes, manufacturers very often apply additional criteria to concrete mixes. The basic one is the requirement for concrete mixtures not to contain fly ashes, as they tend to gather in the upper layer of the panel, which can increase flooring’s dusting and can result in loosenings. The use of appropriate cement – mainly low alkaline [NA) is also an important criterion. The most often recommended cements for flooring concrete with a hardening layer are: CEM I, CEM ll/A-S, CEM ll/B-S, CEM lll/A.

As far as the hardening layer is concerned, it is recommended [3] for concrete surface to be wet. Any excess water should be removed. The surface should be refreshed with a trowelling machine’s disc, and then, about half of the provided amount of dry-shake material (2-2.5 kg/m23) should be spread out and pre-trowelled with a disc. Only later the second batch of material (2-2.5 kg / m2) should be scattered and trowelled with a disc again. At the stage of spreading, the material consumption should be controlled so that it is evenly and adequately spread (usually 4-5 kg/m2) on the surface.

The hardening floorings performance characteristics declared are relatively constant. Example properties apply to:

  • abrasion resistance – classes close to A3 – 2.70 cm3/50 cm2,
  • thickness of the dry-shake layer approx. 2-3 mm,
  • compressive strength approx. 80 N/mm2,
  • exposure class XM 3.

According to the PN-EN 206 Standard (41 concrete mixes should be designed taking into account the environmental impact. In order to do so, exposure classes have been defined giving a description of aggressive environments for concrete and reinforced concrete structures. The division was made Based on corrosive factors such as: carbonation, non-seawater and seawater chloride corrosion, aggressive impact of freezing and thawing without de-icing or with de-icing agents, and chemical aggression. The latest edition of the PN-EN 20B (41 Standard of 2014 does not define exposure classes for aggression caused by abrasion.

In construction projects, concrete specifications with classes adequate for environmental exposure are given by designers very rarely. Therefore, by default, if no class is given, the contractor assumes the class described as X0, which corresponds to no threat by environmental aggression or corrosion hazard.

Drawn up by:

Karol Sadłowski, M.Sc.

Damian Urbanowicz, M.Sc.

Maciej Warzocha, M.Sc.

References

  1. PN-EN 13318:2002 Floor Screeds and Materials to Make Them. Terminology.
  2. AGI 302. 1R-04; ACI Committee 302, Guide for Concrete Floor and Sfab Con- struction. America Concrete Institute, 2004.
  3. Bautech Sp. z o.o., Product Data Sheets.
  4. PN-EN 206:2014-04 Concrete. Requirements, Properties, Production and Compliance.
  5. Ryżyński, Concrete Floor Surface Hardening, “Construction Engineer”, No. 4/2015.
  6. Chmielewska, G. Adamczewski, Defects and Repairs of Industrial Surface Hardened Floorings, Materials of the XXVI Scientific and Technical Conference “Construction Failures”, 2013.
  7. Rainer Sasse, Design and Performance Requirements, “Industrial floors” Scientific and Technical Seminar, 2007.
  8. Szydło, Road Surfaces Made of Cement Concrete, Polski Cement Sp. z o.o., 2004.
  9. IBDiM, GDDP, Catalogue of Typical Rigid Surface War­szawa 2001.
  10. DIN 18202 Toleranzen im Hochbau – Bauwerke Tabelle 3.
  11. PN-EN 12620+A1:2010 Aggregates for Concrete.
wpis 07

Work at height– HSE Requirements

I. Work at height – Definition

Work at a height relates to the work done on the surface at the height of at least 1.0 m above the floor or ground..

Work at height does not include any work delivered on the surface, regardless of the height, if this surface:

– Is covered from all sides to a height of at least 1.5m with full walls or walls with frames,

– Is equipped with other fixed structures or devices to protect the worker against fall from a height.

Work at height should be organized and performed in a manner that prevents swinging outside the balustrade railing or outline of the device on which employee stands. On surfaces built to a height of 1.0m above the floor or above the ground, where due to their nature works may be delivered by employees, or as a transition, the railing should be installed consisting of protective rails at least 1.1m high and curbs at least 0.15m high. The midrail shall be placed between the handrail and curb, or this space should be filled in a way that prevents falling. If due to the type and conditions of the execution of the work at the height, the use of railings, referred to above is not possible, other effective measures shall be provided for the protection of workers against falls from a height, suitable for the type of delivered work.


 II. QUALIFICATIONS REQUIRED TO DELIVER WORK AT HEIGHT

Work at height shall be delivered exclusively by employees:

– Who hold a medical certificate confirming absence of contradictions to work at height. A referral regarding medical examination shall include annotations specifying work at height, namely 3m above the ground or less.
– Trained in the field of occupational safety that completed job specific safety training to familiarize them with the nature of work and possible hazards at the given workplace.
– Provided with personal protection equipment and familiarized with operation thereof.

To provide safety appropriate organizational measures may be provided or physical measures, e.g..:

– Fall protection system including assistance of other employee,
– Barriers, guards,
– Equipment protecting against fall from a height,
– Signage and site access security.
– Familiarizing with risk assessment analysis related to delivered work.
– Familiarizing with instructions and procedures applicable at workplace.


III. WORK AT HEIGHT AS SEVEREALY HAZARDOUS WORK.

As work at height is classified particularly hazardous, the employer is obliged to ensure safety during work delivery. In this regard the employer is obliged inter alia to:

– Designate a person supervising delivered works;
– Provide suitable personal protection equipment and collective protection measures;                               – Provide employees with job specific safety training.


IV. WORK MANAGEMENT

  1. Work delivered on scaffold and mobile access platforms

Scaffold and mobile access platforms shall be delivered according to manufacturer’s documentation or individual design. Scaffold shall be erected on stable and level ground, with gradient allowing flow of storm water runoff effluent. Quantity and location of anchoring and anchoring force shall be specified in the design or manufacturer documentation. Scaffold and mobile access platform shall be provided with the plate specifying the following:

  1. a) Data of contractor erecting the scaffold or mobile access platform, including his name and surname, or Company name and phone;
  2. b) Permitted load capacity of catwalks and scaffold or mobile access platform structure.

Scaffold and mobile access platforms shall:

  1. a) Be provided with catwalks of working area sufficient to quantity of personnel delivering works and store tools and materials required for works;
  2. b) Feature with stable construction to transfer load;
  3. c) Be provided with the top rail and vertical circulation.

Assembly, operation and dismantling of scaffold and mobile access platforms is not allowed:

  1. a) At night, unless lighting is provided that ensures good visibility;
  2. b) During dense fog, rainfall, snowfall and icing;
  3. c) During storm or wind speed over 10 m/sec.

Scaffold operation and use may follow, if acceptance inspection has been carried out by site manager or other authorized person. Acceptance of scaffolding shall be confirmed with records in site log or pre-operational inspection report. Scaffold and mobile access platform shall undergo regular checks performed by site manager or other authorized person following strong wind, precipitation, downtime over 10 days, and on regular basis at least once a month. The scope of activities performed in terms of check was specified in manufacturer’s manual or design.

Works related to assembly and dismantling of scaffold and mobile access platform shall be delivered by qualified persons only.

  1. Portable ladders

During use and operation of portable ladders it is not allowed to:

  1. a) Use any damaged ladder;
  2. b) Use a double sided ladder as a straight ladder;
  3. c) Position a straight ladder against slippery surface, light or movable objects or piles of materials that do not guarantee required stability;
  4. d) Position a ladder in front of closed door, unless locked with a key from the side of positioned ladder;
  5. e) Position a ladder on unstable ground and in vicinity of machinery and other devices in manner that poses risk for employees working on ladder;
  6. f) Carry a ladder over 4m long by one person;

A straight ladder shall protrude 1m over the surface where it is leading to, and angle shall be 75°.

Every time adhere to the following rules regarding use of ladder:

  1. a) Works related to painting may be delivered on a double sided ladder only up to height of 4 m from the floor;
  2. b) Ladder without brackets that is over 4m long, shall before carrying or assembly be provided with a vertical guide to allow installation of automatic restraint device connected to safety rope of harness;
  3. c) During works on rope ladders persons shall be protected against fall from a height with the vertical guide, installed independently of load carrying ropes;
  4. d) Delivery of works related to plastering and masonry on a straight ladder is not allowed;
  5. e) Works on ladders related to rough carpentry may be delivered up to height of 3m.
  1. Fixing brackets and other devices

During works on fixing brackets and other devices not purposed for presence of people, delivered at height up to 2m over the floor or ground, if delivery of works require swinging outside the balustrade railing or outline of the device on which a person stands, or adopting another forced posture that poses risk of fall from a height, the following protective measures shall be provided:

  1. a) Fixing brackets, catwalks and other stable devices with protection against accidental displacement, and of sufficient load capacity;
  2. b) Access walkway that meets the following requirements:
  3. c) Working area sufficient to quantity of personnel delivering works and to store tools and materials required for works,
  4. d) Floor shall be level, and permanently fixed to the structural elements of walkway,
  5. e) Information shall be provided in visible manner on walkway regarding permitted load capacity.
  1. Works related to poles, posts, towers, chimneys, civil engineering structures without structural floors

If nature of delivered works require swinging outside the balustrade railing or outline of the device on which a person stands, or adopting another forced posture that poses risk of fall from a height, it is required in particular to:

Before work commencement:

– Check the condition of the structure or equipment on which works are to be carried out, including their stability, load capacity;

– Protection against accidental displacement;

– Condition of the fixed structures or devices designed to be used for the attachment of lifelines.

Employees delivering work:

– Shall be provided with equipment appropriate to the type of work performed that protects against fall from a height, namely: a safety harness with a lanyard attached to the solid parts of the structure, the safety harness with a lap belt (for works delivered on poles, masts, etc.), safety helmets.

Legal basis:

The Regulation of the Labour and Social Policy Minister as of 26 September 1997 on general provisions for safety and hygiene at work. Consolidated text:  JoL from 2003. No. 169, item 1650 as amended.

Prepared by:

HSE Specialist

Tomasz Leliński

wpis 06

Training Regarding Racking Inspection

The previous newsletter covered the subject related to racking inspection and today we will focus on knowledge and skills required from warehouse personnel to conduct the inspection in proper manner. Again as a starting point for the discussion will be regulations, namely references to PN-EN 15635:2010 Standard which provides the following information:

8.1.3 Training

Operators shall undergo training regarding operation of storage systems and equipment (see B.3).

B.3 Training

Users of storage equipment shall consult product manufacturer to determine procedures for safe operation and provide training for the whole personnel responsible for operation.

The following provision of this standard relates to further training provided for operators:

D.2.2.2 Prevent risk of recurring defect

 

To eliminate risk of accidental damage causing poor strength of storage system, the key is to reduce or prevent any recurring defect or damage. For this purpose good practice is useful, including:

– Provision of trainings for fork lift truck operators * (* author’s addition);

Moreover  according to requirements the user shall designate a person responsible for safety of storage systems. Such person shall be instructed regarding identification of system supplier to contact him and provide training required to keep systems in good repair and ensure occupational safety.

Also the respective racking system operation manual includes similar information regarding further trainings for personnel responsible for safety.

At present any racking supplied to the customer is accompanied with manuals including inspection reports. These reports facilitate provision of regular inspections, however persons in charge often do not possesses broad knowledge in this regard. Inspections shall be performed on regular basis (according to specified interval) and shall include some checks according to the requirements laid down in applicable regulations. Also classification of deviations is very important, as well as taking proper steps  to protect the work area until repairs are provided.

As a control inspector performing professional inspections I am obliged to check, if inspections were performed and identified deviations and damages were recorded. From my own experience I can say that despite eagerness and honest attempts of persons responsible for inspections, these reports very often showed inaccuracies and evident misconduct. Let me quote some very common mistakes that may be avoided, thanks to specialist training and preparation of a person in charge.

 

Improper assessment regarding an identified damage e.g. racking frame upright relates to two issues. The first one relates to measurement indicating necessary replacement and consequently yellow code to be used (yellow, red code), instead of green code that would be wrong in this case. In consequence replacement of component is necessary. In this way some employees are unknowingly exposed to the hazard. The second case relates to contrary situation, where a defective part has been classified for replacement. This will result in additional costs to be incurred by the employer.

Other oversight relates to some aspects connected to pallet management. Note that warehouse staff is obliged to report to a person responsible for occupational safety any defects and unapproved pallets that shall be put out of operation immediately.

Finally we need to mention an absence of locking pins securing racking beams. Each time during inspection any missing pins shall be installed to ensure total safety  and prevent system malfunctions.

Considering the above cases and being aware of the need regarding enhancement of competences, as well as increasing the awareness of warehouse personnel ZMS offers comprehensive training regarding performance of racking system inspections. Due to specific nature of this issue, the training includes subjects and fields that will allow participants to perform the inspection on unaided basis (supervised by instructor). To find out more about the training please contact ZMS.

 

wpis 08

Warehouse Operation Management – Rules

Pursuant to the Regulation the Minister of Labour and Social Policy as of 26 September 1997  on general provisions of occupational safety and health as amended, the employer is responsible for occupational health and safety, in particular prevention of hazards related to provided work, work management, precautions, as well as provision of information and training for employees.

Designation of spaces and principles regarding storage of materials.

  1. For any material or good purposed for storage it is required to:
  1. a) specify storage spaces as well as manner and allowed storage height for any type of goods;
  2. b) ensure that mass of stored goods was within load range permitted for storage system or equipment (racking, platforms etc..);
  3. c) ensure that mass of stored goods, including mass of storage system and devices, including handling and transport systems, was within load range permitted for floor topping and structural floors where storage follows;
  1. a) Racking shall offer robust and stable construction and be provided with protection against collapse.
  1. b) Aisles width shall be appropriate to used equipment and shall enable safety during equipment maneuvering and operation.
  1. a) Stacking of goods on racking and handling thereof shall not result in hazard for employees.
  1. b) Any fragile goods, substances and preparations classified hazardous, as well as materials of higher mass shall be stored on the lowest shelving.
  1. a) Objects whose size, shape and mass require individual manner for storage, shall be stacked in manner ensuring stability, considering their centre of gravity, to prevent tipping over or fall.

 

  1.  a) In case of piled materials storage it is required to ensure:

– stability of piles by storage up to height limit appropriate for type of materials (size, mass, shape) and packaging durability;

–  stack by interlocking layers to keep them secure;

–   that centre of gravity of stored piled goods was within the pile;

–  a distance between piles that enables safety during handling of materials.

  1. b) During removing any goods from the stack, start from the top row first. Never remove any goods placed in the middle of pile.


6.1 In case bulk materials storage, ensure:

– Storage spaces that will enable free access and aisles around a pile in case of bulk materials disposing at natural angle;

– Sufficient strength of barriers appropriate to force generated by stored bulky goods;

– Appropriate fencing off, if required to protect adjacent spaces, workplaces according to technical possibilities– for areas where handling follows and handling equipment, with provided connection to extraction systems, if dusting follows;

– Work procedures ensuring safety, in particular in case of manually handled and carried materials.

2. Climbing bulky materials heaps may follow only, if necessary, provided that an appropriate platform or other protecting equipment was provided, as long as an assistance of second employee and supervision is provided.
During storage of bulky materials that cause risk of dusting, tight fencing off is required min. 0.5m high over the stored goods.

  1. 2. Transport of goods referred to in clause 1, may be provided with special transport means or in closed containers.
  2. During storage of goods that pose risk of self-ignition, always appropriate means of protection shall be provided, in particular with reference to storage height, provision of ventilation and shifting heaps or piles on regular basis.
  3. Storage is not allowed directly under overhead power lines or at the distance (counting from the location of end cables) smaller than:

1) 2m – away from low voltage line;

2) 5m – away from high voltage line up to 15kV;

3) 10m – away from high voltage line up to 30kV;

4) 15m –away from high voltage line over 30kV.

Circulating spaces for manual or mechanical moving of materials.

Pursuant to § 4 section 2 of the above Regulation on general provisions of occupational safety and health, of the following wording: transition should have dimensions appropriate to the number of potential users and the type and size of used equipment and moving cargo. The minimum dimensions are laid down in the Polish Standards.
Transition between machines and other devices or walls intended only to support these devices should have a width of at least 0.75 m. If the crossing is done bi-directional traffic, their width should be at least 1m.

PN-M-78010:1968 Standard on intra-factory transportation – Roads and door openings – Guidelines regarding design laid down the guidelines regarding warehouse building circulating areas designing. For motorized vehicles in one-direction traffic (without pedestrian traffic and other vehicles) minimum width of road at straight section shall be

B = a + 60cm
Where: a means width of transport mean, alternately width of load, if load width is over the truck.
Road width B shall not be below 120cm.
If pedestrian traffic is possible at the same time, B width shall be at least:
B = a + 100cm
In case of warehouse with bi-directional traffic, road width for fork lift truck shall be minimum (excluding pedestrian traffic):
B = 2a + 90cm
and in case of pedestrian traffic and other vehicles road width shall be:
B = 2a + 200cm
Pursuant to PN-EN 349+A1:2012 Standard on Safety of machinery-  Minimum gaps to avoid crushing of parts of the human body a safety gap between the truck and racking shall be minimum 50cm. It is a gap that ensures safety for humans (in case of any human staying within aisles).

Warehouse signage including information, warning signs and regarding applicable procedures.

Pursuant to § 66 of the Regulation the Minister of Labour and Social Policy as of 26 September 1997  on general provisions of occupational safety and health as amended, the employer is obliged to:

  1. Establish the rules regarding traffic code applicable for intra-company circulation, consistent with the provisions of traffic code.
  2. The rules of traffic code referred to in 1 clause, maximum speed limit shall be established for transport means, intra-company circulation and company spaces, appropriate to road width, traffic, visibility etc..
  3. Roads shall be provided with road signs consisted with the applicable traffic code.
  4. Pursuant to the Regulation of the Minister of Economy on occupational safety during motor-driven trucks operation, the employer is obliged to specify speed limit for truck operation at particular road sections, taking into account traffic, nature of cargo, road width and condition, as well as visibility.
  5. When driving the road purposed for truck and provided with barriers separating from pedestrian walkway, the speed limit is 12 km/h, if distance is maintained from the nearest truck corresponding to ca. four times of truck length.
  6. Jeśli jest to droga oddzielona od drogi dla pieszych za pomocą linii na powierzchni drogi, to dopuszczalna prędkość maksymalna wynosi 5 km/h. 5 km/h jest normalną prędkością z jaką porusza się osoba piesza. Jeśli na drogę wtargnie pieszy, to niezależnie od odległości od wózka miejsca wtargnięcia, kierowca powinien wózek zatrzymać do czasu opuszczenia drogi przez pieszego.

The above guidelines applicable in many American states are based on guidelines from ASSE (The American Society of Safety Engineers).

Prepared by:

Tomasz Leliński

HSE Chief Specialist

wpis 05

How to Perform Racking Inspection?

In 2018 ten years passed since introduction of PN-EN 15635 Standard on application and maintenance of storage equipment. This paper related to some significant issues crucial for safety during racking system operation from the perspective of inspector responsible for racking inspections.

Today you do not have to remind employers or responsible services about the importance of regular racking inspections. Note that there are three basic types of inspections, namely:

  • An immediate reporting
  • A visual inspection
  • An expert inspection

Starting from the beginning: it is a personnel responsible for occupational safety in the given Company that is responsible for familiarizing a newly engaged fork lift truck operator with procedures that minimize risk of hazard for rack system and its environment where he will be performing his work every day. During such training the operator shall be familiarized with procedures regarding reporting any hazardous incidents or possible risks. Good practice includes training for newly engaged employees in the field of racking operation based on operation manual delivered by system manufacturer. This practice also prevents hazards and risks generated by an employee. Any reporting shall be recorded and attached to racking documentation.

Other type of supervision relates to a visual inspection that shall be performed by a person responsible for monitoring of rack system safety. In practice such inspection is conducted most often by warehouse head. Similarly to the immediate reporting, the visual inspection shall be performed in official manner also.

Moreover such inspection shall be performed in regular interval, as specified on basis of risk assessment analysis.

The routine inspections performed most often by the user are complemented by the expert inspection provided usually by an independent company. The independent service reduces risk of omission or overlooking any issues crucial for safety during racking operation. The performed properly inspection assumes a hierarchy-based approach to the aspects related to controlling. In practice it means that the inspection will be performed at a few levels, where identification and classification of damages results in recording thereof in relevant records, or at least it shall be provided in this manner.

The below issues relate to situations that shall be checked in terms of expert inspection. In case of any identified irregularity or malfunction, it shall be recorded in the racking inspection report.

Very important are the aspects related to assembly and installation of racking e.g. modifications of racking configuration. During the inspection, owner’s records regarding racking shall be checked precisely. Such records shall specify e.g. racking layout along with storage levels and permitted structure loading capacity.

Other check relates to condition of pallets and other devices used for storage of goods. Although it is very important, still very often it is overlooked. The first criterion that shall be taken into account with regard to pallet management relates to degree of wear and identified damages. The quoted standard (C Annex) specified some damages and defects whose presence requires to put the pallet out of use. And it is the user who is responsible for regular and detailed checks of pallets. Note also that use of pallets other than specified by system designer is equivalent to racking operation contrary to its intended purpose and may result in serious consequences.

The subject of next verification relates to supplier’s liability. Actually absence of report regarding acceptance of racking or its improper form is deemed negligence.

Finally verification is carried out regarding user’s liability. During expert inspection, an inspector is obliged to check, if a person responsible for safety conducted regular inspections of racking, and consequently notifications also.

The above issues specify the scope of expert inspection and draw user’s attention to the form and contents of reports produced by a Company engaged to perform the inspection.

Although since 1 January 2003 standards are not applicable any more, still the first pages of this standard specified the guidelines along with PN-EN 15512, EN 15620 and EN 15629 Standard to ensure that the entity establishing the specification, the user and designer were aware of limitations in respective disciplines, to ensure safety of prepared design.

Our Company offers wide range of services related to inspection of racking and we also provide trainings in the field of racking inspections. We are looking forward to provide you with further information.

Prepared by ZMS Systemy Magazynowe

wpis 04

Warehouse Mezzanine Erection– HSE Requirements

Mezzanine is a best solution to expand storage spaces.

Mezzanine provides an additional structural floor that may be installed inside high warehouses to expand significantly storage spaces. This way you can also separate administration spaces from the production floor.

What are the key features of mezzanine structure

To answer this question we need to quote the definition of mezzanine.

Pursuant to § 3 clause 19 of the Regulation of the Minister of Infrastructure as of 12 April 2002 on technical conditions, which should correspond to the buildings and their location (JoL 2015.1422 as of 2015.09.18), a mezzanine relates to the upper storeys or rooms above an intermediate floor less from the surface of the floor or room, an unclosed construction divisions from insides, from which it is separated. According to this definition, Any additional spaces shall be deemed the mezzanine, if area thereof is less than area of the warehouse. Consequently this relates to warehouse area where mezzanine is to erected.

Preparation is crucial.

Mezzanine erection may result in change of building performance or technical parameters. In this case erection may cause alteration of existing structure (warehouse).

Pursuant to Art. 28 § 1 of building law, the building permit is required in this case. Mezzanine has not been listed in Art. 29 of building law, which indicated objects and civil works which do not require a planning decision. Neither notification referred to in Art. 30 of the above act applies in case of mezzanine erection.

When useful floor space is below 1000m2, and it is impossible to meet some requirements specified in § 2 of the Regulation on technical conditions, which should correspond to the buildings and their location, as well as those included in Art. 5 and 6 of building law, the Investor shall comply with § 2 clause 2 of the above Regulation which allows other solutions to be employed upon approval of competent authorities, e.g. Fire Service.

However before commencement of works follow in terms of mezzanine erection, firstly the design documentation shall be produced and location of mezzanine shall be specified.

Mezzanine erection results in many changes of warehouse management.

Actually before erection of mezzanine the following shall be considered:

  • Ground bearing capacity
  • Quantity of emergency exits
  • Quantity of fire equipment (in particular fire extinguishers, fire hydrants)
  • Fire escape routes
  • Access to emergency exits (exit access)

Mezzanine location may result in more people employed in warehouse and consequently quantity of escape routes and emergency exits required, as well as the erection of mezzanine itself (stair width, landing width etc..).

Pursuant to § 236 section 1 of the Regulation on technical conditions, which should correspond to the buildings and their location, spaces occupied by people shall ensure escape outside the building or to adjacent fire zone, directly or using circulation spaces hereinafter referred to as ”escape routes”.

  • 236 section 6 of the above regulation provides that the required width and quantity of accesses, exits and emergency routes provided in the building, whose intended purpose and development did not indicate clearly the maximum number of occupiers, shall be specified with reference to the area, namely:

Warehouses– 30 m2/person.

Pursuant to § 237 the spaces the be provided with access hereinafter referred to as “exit access” from the furthermost place, where human may stay, to the emergency exit leading to emergency route or other fire zone or outside the building, of length below:

  1. 75m within fire zones PM of fire load over 500 MJ/m2, in case of building with more than one storey above ground;
  2. 100m within fire zones PM, of fire load below 500 MJ/m2, in case of building with more than one storey above ground and fire zones PM of building with one storey above ground regardless fire load.

The construction of mezzanine shall take into account a quantity and type of goods purposed for storage.  The mezzanine shall be anchored properly to the ground.

Each storey shall be provided with label clearly stating load bearing capacity per m2.

Employees shall always adhere to the specified load bearing capacity when handling stored goods.

Mezzanine may also provide two or three additional storeys inside the production building with circulation provided with stairs or an elevator. Circulation between mezzanines at the same level is possible thanks to special platforms. Mezzanines, stairs, platforms shall be protected with barriers.

Width of mezzanine stairs providing emergency exit shall be calculated proportionally to number of people staying on the storey at the same time, where more people is allowed, and shall be minimum:

  1. A) 1.2 – Stair flight width

1.5 – standing width

0.175 – step height – for warehouse with more than 10 people employed.

  1. B) 0.9 – Stair flight width

0.9 – standing width

0.19 – step height– for warehouse where more than 10 people is present.

Mezzanine shall be fitted with stair balustrade. Pursuant to § 105 of the Regulation of the Labour and Social Policy Minister as of 26 September 1997 on general provisions for safety and hygiene at work, (JoL 2003.169.1650 dated 2003.09.29) work at a height within the meaning of regulation is the work done on the surface at the height of at least 1.0 m above the floor or ground, excluding the wall of height from mezzanine floor up to the ceiling.

The mezzanine shall be provided with barriers preventing fall installed from each side. Barrier shall be 1.1m high and shall be provided with toeboard– 0.15m wide and rail 0.55m high.

Each storey of mezzanine installed within warehouse shall be at least 2.2m high.

Pursuant to § 20 of the Regulation of the Labour and Social Policy Minister as of 26 September 1997 on general provisions for safety and hygiene at work (JoL 2003.169.1650 dated 2003.09.29), spaces related to: personnel room, guard room or exchange office in the warehouse, and located at the goods storage level or the mezzanine open towards warehouse, shall have minimum height of 2.2m in the light

The mezzanine may be used to deliver administration and office works, at location where employees will not be exposed to noise inside the production building. Office located at the same level where storage operations are carried out prevent and contributes to dialogue with employees. Consequently efficiency of building management is enhanced.

Note also barriers protecting office wall against impacts by e.g.: manually operated pellet truck or battery truck.

Fire-fighting equipment provided on mezzanine.

Pursuant to the Regulation of the Minister of Internal Affairs and Administration as of 7 June 2010 concerning the fire protection of buildings and of other construction objects or premises (JoL No. 109, item 719), the mezzanine shall be fitted with extinguishers. Pursuant to § 32 section 3 of above quoted regulation, extinguishing medium of 2kg (or 3dm3) mass contained in extinguisher shall be provided, except of special cases as specified in further regulations, for each:

  1. 100 m2 area of building fire zone, when without automatic suppression system:
    a) classified to ZL I, ZL II, ZL III or ZL V human hazard class;
    b) production and storage spaces with fire load over 500 MJ/m2
    c) areas including spaces where explosion hazard is possible

A distance between extinguishers shall not be over 30m.

Designation of location for mezzanine is not easy matter and requires some expertise.  Before commencement of works related to mezzanine erection in warehouse, you need to prepare well.

Actually the best practice is to consult specialists possessing expertise and experience in the field of mezzanine erection.

Prepared by:

Tomasz Leliński

HSE  Chief Specialist

wpis 01

Storage Equipment Collapse– Do’s and Don’ts?

Storage systems have been designed for use in warehouses. However to ensure long service life as well as total safety for users there are some limits to this performance. So what is recommended?

Load capacity limits

Unfortunately racking in many warehouses is exposed to load exceeding its loading capacity due to quantity of stored products and goods. It may be caused by the following reasons:

  • Absence of plates providing information regarding maximum permitted load. Actually it is the employer who in charge of such signage provided in visible manner.
  • Absence of spaces. In warehouses where spaces are limited and many products are on stock employees must be very creative to keep on with all operations. Therefore they place products one on other what results in racking excessive loading and other consequences for users.

How to avoid collisions

Accidental impacts generated by fork lift trucks may cause serious damages to the racking. At first sight such collisions seems not to be risky at all, as each racking features with robust structure. However impacts that follow every day (what is very common in warehouses), result in serious damages of structural components of racking. Very often narrow instead of operators aisles that make maneuvering very difficult may be blamed for this collisions. Therefore such issues shall be taken into account at design phase.

The key for each user is to consult professionals who possess experience and expertise is n this regard. Avoid building independence. Always engage reliable and proven professionals! Note that any modification of racking configuration may result in serious losses. Our highly qualified team of experts is looking forward to provide professional services.

Inspections

With regard to professional services note that also inspection of racking shall be performed on regular basis and in professional manner by highly qualified and trained personnel. Regular inspections prevent situations that pose hazard for human life and health. Moreover such inspections prevent costly repairs and downtime what increases efficiency of equipment and insures Company smooth operation.

How about sharing your opinion and experience regarding proven methods that ensure safety during racking operation?

wpis 03

Office Racking– What to Choose?

When speaking about racking (that is quite often in fact), we most often mean the system dedicated for warehouse purposes. And there is nothing strange about it? Actually it is this place where we work or where our equipment is stored. But? How about other spaces where racking system may provide space-saving storage?

How about office spaces?

For many of us thinking about office spaces brings to mind small spaces fitted with a desk and chairs only. What about big office spaces, accounting companies where an every shelf counts? Actually binders are stored there under shelves packed with many books that make it impossible to find anything. Have you ever experience that? We did too. Therefore we offer a proven solution.

Is any solution available?

It may seem that office spaces are fitted mostly with standard racking packed with books and clattered with multitude of documents and other objects. You can’t be further from the truth. The owner of every business is focused mainly on durability, efficiency and usefulness. An our racking system offers all of them. The shelving system meet any document storage needs: offer strength and load capacity. Thanks to this biggest advantage this system is perfect for any office spaces. Additionally specially designed drawers, spacers or separations will be useful to store documents in order. Does this sound reasonable to you?

Questions?

We are aware that every industry and discipline is unique, therefore please contact us to find out more about solutions tailored to individual needs? Our specialist will be happy to provide consulting services, further information and answer any question. We look forward to provide you with details!

wpis 02

Professional Warehouse

The warehouse is crucial for business activity in many Companies. Warehouse smooth operation depends on its employees, installed equipment, as well as maintained records. So what is behind the professional warehouse?

Top quality equipment

Our focus is top quality. The equipment should ensure reliable operation for many years therefore cheap solutions will not bring desired effects. Each warehouse shall offer functionalities that may be provided only thanks to racking that increase storage spaces and offer load capacity appropriate to stored goods. When you begin to stock goods in warehouse precise calculation regarding shelf maximum load shall be performed. Note also that proper signage is also important and contributes to employee efficient work.

IT system selection

In our days it is impossible to do without computers? Warehouses are computerized also. Therefore the professional warehouse shall be fitted with IT system that will control all operations: including records of stock, receipt and release of goods or regular  stocktaking. Such IT system facilitates greatly works in terms of warehouse management.

Employees make for the heart of warehouse

It is very true that it is employees who build Company strength and its image, and every owner should heed these words. A qualified personnel is very precious in our days. The professional warehouse is operated by qualified and trained personnel and offers total safety for any type of performed works. Therefore uncompromised occupational safety shall be the priority both for managers and company owners.

How about sharing your view regarding the professional warehouse?