Climatic conditions occurring during a group accident at NIWKA-MODRZEJÓW hard coal mines in Sosnowiec on 24 February 1998 , together with realisation of recommendation after the occurrence in order to improve the safety standards.

On 24.02.1998 between 1³⁰ a.m and 22²² hours at NIWKA-MODRZEJÓW hard coal mines an accident took place in the ventilation dip road in seam 418 at the level of 600m.

The accident took place while:

• a blind roadway working was being explored
• assistance was being rendered to those affected
• running of emergency rescue works.

In the result of that event 10 rescuers were affected, out of whom:

• 6 lost their lives
• 1 suffered from serious injuries
• 3 suffered from light injuries.

Penetration and the course of rescue work in dip ventilation road in seam 418 (figure No 1)

Dip ventilation road of the length of 740 m and inclination of 13^o was executed in 1990.
It was to constitute, in some sense, a ventilation-transportation road for designed longwalls in seam 418. Because of tectonic disturbances occurring there and therefore shortening of the longwalls advance in seam 418 the dip became redundant. The ventilation dip ( fig 1) had connection with water drainage -transportation dip road and after partial flooding of water drainage-transportation dip, it became a blind working. Because of that air-duct ventilation was executed in the ventilation dip road. It was needed for ventilating of the working since at the crossing of dips pumps were installed for dewatering of the region. This pumping station was active from October 1994. Then the pumping station was liquidated together with the pipeline and the air-duct in the ventilation dip road. Then the dip was sealed off by construction of a brick stooping (TI-33) on the intake to stone dip road 2 from the eastern crosscut I.

Figure 1. - Fragment of the workings’ plan

In November 1997 drilling of a stone dip to seam 510 in the floor of seam 418 was started, The dip at its advance was to cut through the isolated ventilation dip road. The exploratory borehole (protection hole) executed from the front of the face of the stone dip road to ventilation dip showed there was water in the sealed off working. Because of filling up of exploration borehole it was not possible to determine what hazard can the water create in case it will get an entrance via a working being derive.

On 23 February on the third shift at 21 ⁰⁰ hrs, during allocation of work tasks, the ventilation overman gave a disposition to a rescue team on stand by to take additionally three pieces of AU-9L oxygen self rescuers and then gave a disposition to the team to go to the zone of TI-33 isolation stopping. The team’s task was to make a hole in the stopping and penetrate the ventilation dip road.

On 24.02.1998 at about 1⁰⁰ o’clock a.m. three rescuemen and the foreman of the dust fighting division got through the hole in TI-33 stopping to ventilation dip road, being equipped with oxygen self rescuers AU-9L. During exploration, when they were about 465 m from the stopping there rescuemen fainted and the foreman, as the only person. managed to withdraw to a fresh air current. He informed about the incidence the ventilation overman of the division who, about 1.³⁰ a.m. together with two remaining rescuers being in the zone of the stopping and equipped with W-70 working oxygen breathing apparatus, went into the working reaching the three fainted rescuers. At that site the ventilation overman got fainted and the two rescuers, after trying to take him away withdrew to call for assistance, calling the second rescue team being on stand-by at this mines. About 2³⁰ a.m. the team, equipped with W-70 oxygen working breathing apparatus and two AU - E oxygen self rescuers and instruments for monitoring of mine air composition , entered the working. One of the rescuers stated that the ventilation overman did not show any sign of life. Going farther down the working the team encounters sequentially the three rescuemen lying on the floor. Because the rescue team members lost their strength the rescuers withdrew to the hole in the stopping. At 3¹⁸ the mine’s dispatcher was informed about the accident. The dispatcher informs the managerial personnel of the mines responsible for mining operations and then the mine’s rescue station, Regional Rescue Stations in Sosnowiec and in Jaworzno, and other persons following the rescue scheme of notification. The arriving rescue teams, by disposition of the man in charge of rescue works, entered the ventilation dip road. Because of very difficult climatic conditions (temperature from 26 to 31,5⁰C and humidity from 95 to 98%) and because of death one of the rescuers the man-in-charge of rescue works takes a decision to install a separate ventilation. The further works consisted in connecting of sequent sections of air duct to operating fan and winding off of the chromatographic line for sampling the air. After reaching the affected rescuers the rescue teams took them away to the fresh air base. In total 60 rescuers attended the rescue works. The works were terminated on 25 February 1998 at 0³⁰ a.m.

After 11 days at a hospital one of the affected rescuers died.

Establishing of a Committee.

In association with the group accident at NIWKA-MODRZEJÓW hard coal mines in Sosnowiec on 2402.1998 the Chairman of the Mine Authority established a Committee with the aim to investigate the causes and circumstances of the occurrence. As the result of the Committee’s work the causes of the accident and the recommendations have been, among others, determined.

Causes of the group accident

The causes of the group accident occurring during penetration and rescue works connected with rendering of the assistance to those affected were as follows:

1. Admission to penetration of the working without earlier exploration and analysis of ventilation-climatic conditions.

2. Carrying out of penetration of the working in the way infringing the elementary principles of work organisation of rescue teams in atmosphere not fit for, that consisted in:
   • not equipping the rescue team with indication tubes for detection of O₂, H₂S, NO₂, H₂ and rescue phone,
   • execution of a hole in the isolation stopping without earlier exploration of air composition behind it,
   • separation of rescue team members,
   • lack of standby team on site,
   • allowing for penetration of the working by rescuers equipped with AU-9L oxygen self rescuers instead of W-70 oxygen breathing apparatus without phone communication and respective measuring instruments such as: indicating tubes for detection of O₂, H₂S, NO₂, H₂ and a thermometer.

3. Not withdrawing the three rescuers from the ventilation dip road by the foreman of the dust fighting division and allowing for further penetration of the working with the use of oxygen self rescuers AU-9L irrespective that mine air composition indicated to a possibility of occurrence of atmosphere not fit for breathing in a farther part of the working.

4. Opening of the working closed by isolation stopping and carrying out of penetration not in conformity with the rules of rescue works was the cause that:

   • the man-in-charge of rescue works was not appointed,
   • the hazardous zone was not determined, the observation points were not secures and the fresh air base was not founded,
   • only one rescue team was sent for penetration without equipment in necessary controlling-monitoring instruments and phone communication equipment and without the required second team on standby to render assistance.

The cause of the accidents occurring during emergency rescue works consisted in:

1. Difficult ventilation-climatic conditions and mining-technical ones such as:

   • air standstill,
   • increased temperature from 26⁰C to 31,5⁰C at its final section
   • high humidity of air from 95% to 98%,
   • distance from the accident site to fresh air current amounting to about 450 m, considerable lowering of the level of the working, at some places to 1,1 m, and the ambient temperature.

2. Particularly difficult work conditions in rescue apparatus with very limited possibility of heat withdrawing because of high humidity and temperature of the surroundings.
3. Psychophysical features of some of the rescuers or their little experience at work with W-70 apparatus.

4. Limitation of the possibility to render assistance to fainted rescuers while wearing W-70 apparatus because of extended time of their transportation to fresh air current.

5. Undertaking of a justified risk by the necessity to safe people.

Realisation of recommendations after the group accident at "NIWKA-MODRZEJÓW" hard coal mine.

Conclusions of the Committee have been formulated with regard to:

• NIWKA-MODRZEJÓW mine
• underground mines
• mines rescue service
• scientific-research back-up services
• manufacturers of rescue equipment
• institutions responsible for implementation of mining regulations.

Conclusions and the status of their realisation:

With regard to NIWKA-MODRZEJÓW hard coal mine:

1. Take organisation-technical actions to secure of a right manning of ventilation and mien’s dispatching services after checking up of their qualifications - The recommendation has been implemented.

2. Carry out training for managerial personnel and supervisory staff, and in particular dispatching personnel with regard to a correct running of rescue works - The recommendation has been implemented,

 

With regard to underground mines.

1. Supplement the equipment of ventilation and rescue personnel of the mines in individual instruments for measurement of ventilation-climatic parameters, including:

   • oxygen meters for continuous measurement and signalling of the threshold value of oxygen concentration,
   • instruments for continuos measurement of gases concentration, especially CO, CO₂, CH_4,
   • Hygrometers,
   • psychometers,
   • thermometers in numbers indispensable for carrying out of mining operations and rescue works. The numbers will be determined by the mine’s manager in agreement with relevant mines rescue unit.

   The realisation of the above recommendations was carried out as follows:

   • Directors of the Regional Mines Inspectorates , on the basis of art.75 item 2 of the geological and mining law, ordered the mining companies to supplement the equipment of ventilation and rescue services with modern individual measurement instruments for taking measurements of air composition of the microclimate, mines placed the orders for purchase of measurement instruments for the above mentioned measurement in numbers agreed upon with respective regional mines rescue stations,
   • the instruments were supplemented at the mines in the period between 3rd quarter if 1998 and the 1st quarter of 1999.

   During a controlling inspection carried out in 199, regarding among others the status of equipment at the mines’ rescue stations, no incorrectness has been determined.

2. Accept the principle, that:

   • opening up of isolated workings,
   • penetration of abandoned workings,

   will be carried out in conformity with rules and procedures of rescue works, whereas executions of holes leading into the abandoned workings according to determinations done by the mine’s manager.

   Realisation of this recommendation is being accomplished on current basis in conformity with determinations done by directors of regional mines Inspectorates on the basis of the letter of the Chairman Mine Authoritty

3. Get acquainted the interested parsons employed at mines about the causes and circumstances of the group accident that had taken place. - The recommendations has been realised.

4. Introduced a uniform medical documentation for the rescuers that should include all data about his health, including medical investigations results from mines rescue stations, health centres at the mines, registrations of sicknesses, received treatments and sickness leaves.

   The Central Mines Rescue Station in Bytom prepared the pattern of an uniform documentation that has been implemented.

5. Records should be placed in the evidence chart of rescuers from which the number of worked hours in rescue works with the use of breathing apparatus would be univocally evident.

The records are currently done in the evidence books of rescuers.

With regard to the Central Mines Rescue Station in Bytom:

1. Mines rescue units in equipment enabling to improve climatic conditions of rescuers work during carrying out of rescue works in difficult heat conditions, such as:

   • equipment for cooling of air inhaled in oxygen working apparatus,
   • cooling vests,
   • cooling equipment ( coolers), immediate access cooling means.

   Realising this conclusions the standard of equipment for individual Regional Mines Rescue Station has been determined:

   • SAT-2M type equipment for inhaled air cooling in W-7O breathing apparatus manufactured by Factory of Rescue Equipment and Mining Lamps FASER S.A. at Tarnowskie Góry - 15 pieces,

   

   Photo No 2 - SAT 2M - equipment for cooling of air in Polish W-7O breathing apparatus

   • cooling vests manufactured by AMKUS company - 15 pieces

   

   Photo 3 - cooling vest

   After elaboration of technical assumptions, finding of a manufacturer carrying out of test operations and purchase of respective equipment for cooling the site where the rescuers are engaged it is envisaged to provide the following equipment for the Regional Mines Rescue Stations:

   • immediate access cooling means (ventilation partitions, isolations partitions, water vapours),
   • chambers ( tents) supplied with compressed air.

2. Complete the works to implement wireless rescue communications system.

   Within the target oriented project being realised upon the order of the Committee of Scientific Research in Warsaw Technical University and AKSEL Company in Rybnik (manufacturer). The system under consideration was approved for use in underground mines by the Chief Inspectorate of Mines. 10 sets of GABI communication system are at the equipment of the CMRS in Bytom.

   

   Photo 4. Polish radio, rescue communication system GABI

    

3. Terminate works and implement into rescue practice the equipment for rapid installation of separate ventilation.

   The CMRS in Bytom purchased from KLIMAWENT company two portable fans of the WPW-3/500/Ex/3000/G type with flexible air ducts with the length of 110 m. Besides the CMRS, together with KOMAG company from Gliwice, terminated activities targeted at elaboration and manufacture of a light weight, modular air-duct fan fulfilling the requirements of an easy transportation and assembly and possibility of application in workings of small dimensions. With the help of a modular rescue ventilation there is a possibility to form sets to increase capacity and build-up of the equipment allows for reaching of relevant parameters of ventilation adjusted to conditions occurring during rescue works.

   The fan was approved by the Chairman of the Chief Inspectorate of Mines - decision GEM/4716/0021/98/10282/PK/KM from 10.09.1998.

4. Determine the criteria of rescuemen selection with the view of their predisposition to work in difficult heat conditions, and especially tests enabling to determine resistance degree of rescuers to those conditions.

   A team was appointed to realise the recommendation at the CMRS in Bytom that dealt with the problem of modification of the existing "Methodology of medical examinations and criteria of assessment of fitness for work in mines rescue services". Within the task the regulations determining allowable time was verified of reassures work during rescue operations carried out in difficult microclimatic conditions.

   The time of work of rescuers was determined for various cases as:

   • work conditions without extra means improving the climatic comfort,
   • in conditions of SAT-2M equipment usage for W-70 apparatus causing reduction of inhaled air temperature,
   • in conditions of cooling vests application,
   • application of both the means improving conditions of climatic comfort, external and internal within the human organisms.

   The scope and methodology and methodology of investigations were done at the CMRS and then the examinations are carried out by the Specialist Medical Examination and Advice Centre operating at the CMRS in Bytom.

   Besides the work was undertaken on " The influence of microclimatic upon the safety of mines rescuers during rescue operations carried out in difficult microclimatic conditions in underground mines". It was undertaken within the targeted proposal realised upon the assignment of the Committee for Scientific Research in Warsaw and being commonly prepared with the Central Institute of Labour Protection in Warsaw.

   The work will, among others, determine:

   • criteria of the assessment of organism’s predisposition of the candidate for mines rescuer in difficult microclimatic conditions he may encounter during rescue operations,
   • scope of investigations that must cover periodically rescuers ( tests enabling to determine resistance of rescuers to difficult microclimatic conditions),
   • indices determining tolerance of difficult microclimatic conditions by a rescuer and maximum time of work of rescuers under such conditions.

   During the Conference’s debates it is foreseen to acquaint the attendees with the course of the investigations carried out within the framework of this work in heat and humid chamber of the Central Mines Rescue Station.

    

   

   Photo No 5 - tests in heat and humid chamber at the CMRS.

5. Verify the scope of indispensable medical examinations directly before entrance of reassures to rescue works with inclusion of their bodies temperature measurements.

   In order to realise this recommendation the CMRS in Bytom determined an increased scope of medical examinations done by a doctor at the fresh air base directly before the leave the base towards a hazardous zone and suggested improvement of the "Methodology of medical examinations and criteria of fitness for work in mines rescue service..." consisting in introduction of the obligation of carrying out of medical examination of rescuers on surface (for instance, at the mine’s rescue station) directly before they go to underground workings. It is to eliminate a rescue team that is not fully fit to undertake rescue works before the team arrives at the fresh air base and, eventually, mobilising of another rescue team, quarantining a proper conductance of rescue works.

   Additionally the CMRS in Bytom purchased instruments for blood pressure, heart rate and body temperature measurements to provide a possibility for a fast measurement of these parameters of the rescuer’s organism before entering the hazardous zone, in the zone and after coming back from that zone. Also the fitness examinations and criteria of fitness determination for rescuers have been introduced within the framework of rescuers training.

6. The problems from the field of psychology of the rescuers behaviour and that of the personnel managing the rescue operations should be introduced into the training courses programme.

   As early as in May of 1998 the courses programmes for manager of underground

   rescue works and man-in-charge of fresh air bases were supplemented by training in the field of psychology of behaviour during running of rescue works, The following step will consist in introduction of this topic to the remaining training courses carried out at the CMRS in Bytom regarding managing the rescue operations. Therefore it was necessary to employ professionally prepared lectures to run such training.

7. The record will be made in the chart of the rescuers record to be univocally aware of the number of works worked with the breathing apparatus during rescue station" and in the book" Record of the members of the rescue brigade" the discipline was enforced to enter respective records.

8. Undertake works on determination of standard parameters obliging during check up investigation of breathing apparatus in various conditions and prepare a project and implement the apparatus indispensable for introduction of the procedure.

   Within the framework of this recommendation it is foreseen to carry out investigations on determination of standard parameters for check-up testing of the breathing apparatus in various climatic conditions. Such investigations will be carried out in various ranges of temperature and humidity; therefore a climatic chamber has been purchased for, among others, realisation of this recommendation.

With regard to scientific-research centres

1. On the basis of the investigations carried out verify criteria and principals of rescuers engagement in difficult heat conditions.

2. Elaborate procedures of safety management system for carrying out of rescue works in conditions of natural hazards occurring in the mines

3. Prepare technical-functional requirements for portable apparatus for complex measurements of mine air parameters, Within the framework of realisation of item 1 above application has been sent for extra-financing within the central project to the Committee of Scientific Research in Warsaw. The item No 2 is in the course of realisation by the Central Mining Institute in Katowice together with the Central Mines Rescue Station in Bytom. Because of difficult financial situation of research centres the execution of item 3 was undertaken only recently by the Central Mining Institute. Nevertheless provision of ventilation services of mines and mines rescue services with modern monitoring-measurement apparatus for mine air composition secures in a safe and satisfactory manner the ventilation measurement capability in this respect.

With regard to mines rescue equipment manufacturers.

1. Introduce construction changes to breathing apparatus to improve work comfort of the rescuers.

   The above mentioned recommendation is being realised in two stages. The first stage (executed) regards the constructions changes in isolation , working, breathing g apparatus W-70 consisting in a possibility to apply equipment for air cooling called SAT-2M in respiratory circuit.

   The second stage regards elaboration of a new breathing apparatus fulfilling the European standards being realised within the target oriented project called "Regeneration apparatus with compressed oxygen for rescue application". The subject is being realised as the target oriented project upon the assignment of the Committee of Scientific Research in Warsaw. FASER S.A. company in Tarnowskie Góry is the executor of the project and the Central Mining Institute in Katowice is realising research-development works.

2. Elaborate technology of absorption mass production and procedure if quality control to improve parameters of operation of CO₂ absorbers in oxygen breathing apparatus.

   FASER S.A. company in Tarnowskie Góry and SULFOCHEM Ltd Co.in Lubom, producer of ALKASORB, agreed upon new conditions of absorption mass acceptance. The mass constitutes the filling of CO₂ absorbers in oxygen breathing apparatus W-70.

3. Design air, working, isolation apparatus with duration of minimum two hours for underground mining.

   The CMRS in Bytom determined assumptions for the air apparatus referred to as APS/3 in conformity with the requirements of the standard PN-EN 137. After agreement with the construction department of the producer, i.e. FASER S.A. company in Tarnowskie Góry the prototype of the apparatus was made.

   The apparatus was tested in under- and over-pressure system. It is provided with 2 composite cylinders with capacity of 6,8 dm³ each and working pressure of 30 MPa and its total mass, with filled cylinders, is 20,5 kg. The apparatus underwent laboratory tests and practical ones. It did not secure 2 hours of protecting action to wearers, its mass is higher than allowable by 2,5 kg, In its over-pressure version of did not maintain under mask the required over-pressure while investigating the resistance of exhaling. The users stated that while breathing in the apparatus a fast regeneration of breathing takes place after an effort and did not bring forward complaints as to the inhaled air temperature and possessively assessed the way of mounting and adherence of the apparatus to the body.

   • Thus designed and manufactured APS/3 apparatus is at the stage of:
   • agreements at the Central Institute of Labour Protection in Warsaw to obtain the certificate with limitations,
   • approval tests at the CMRS in Bytom and Experimental Mine "Barbara".

    

   With regard to mining regulations.

   It is necessary to establish a team for assessment and up-dating of regulations of the disposition of the Ministry of Industry and Trade from 08.02.1995 on organisation, tasks and equipment of mines rescue ..., with the view to prepare a project of changes in the above mentioned disposition.

   As the fulfilment of the recommendation the Chairman of the Chief Inspectorate of Mines in Katowice established a team for assessment and up-dating of the above mentioned disposition. The team terminated its works in September 1998 suggesting about 70 changes in the text of the disposition. The Protocol of changes was submitted to the team for analysis of application in practice of provisions of geological and mining law that accepted the changes project under consideration. With the letter from 29 December 1998 , sign : PR-022a/161/98-PG the project was submitted to the Minister of Economy for further legislative works.

   On 30 November 1999 Minister of Economy signed the dispositions up-dating the current regulations with regard to mines rescue service, announced in OJ from 2000 No 2, item 24.

   Summary.

   1. Polish mining law regulates in a proper manner the matter of work of employees in conditions of a climatic hazard and work of mines rescuers in difficult microclimatic conditions during eventually conducted rescue works.

   2. The conclusions and recommendations realised and implemented into practice after the occurrence in "NIWKA-MODRZEJÓW" mine in Sosnowiec improve, to a large degree the status of work safety and hygiene in underground mining.