title: Gdańsk

text: Gdańsk has a climate with both oceanic and continental influences. According to some categorizations, it has an oceanic climate (Cfb), while others classify it as belonging to the continental climate zone (Dfb). It actually depends on whether the mean reference temperature for the coldest winter month is set at or . Gdańsk's dry winters and the precipitation maximum in summer are indicators of continentality. However seasonal extremes are less pronounced than those in inland Poland.


title: Gdańsk

text: The city has moderately cold and cloudy winters with mean temperature in January and February near or below and mild summers with frequent showers and thunderstorms. Average temperatures range from and average monthly rainfall varies per month with a rather low annual total of . In general, it is damp, variable, and mild.


title: Gdańsk

text: The seasons are clearly differentiated. Spring starts in March and is initially cold and windy, later becoming pleasantly warm and often increasingly sunny. Summer, which begins in June, is predominantly warm but hot at times with temperature reaching as high as at least couple times a year with plenty of sunshine interspersed with heavy rain. Gdańsk averages 1,700 hours of sunshine per year. July and August are the warmest months. Autumn comes in September and is at first warm and usually sunny, turning cold, damp, and foggy in November. Winter lasts from December to March and includes periods of snow. January and February are the coldest months with the temperature sometimes dropping as low as .


title: Gdańsk

text: The industrial sections of the city are dominated by shipbuilding, petrochemical, and chemical industries, as well as food processing. The share of high-tech sectors such as electronics, telecommunications, IT engineering, cosmetics, and pharmaceuticals is on the rise. Amber processing is also an important part of the local economy, as the majority of the world's amber deposits lie along the Baltic coast. The Pomeranian Voivodeship, including Gdańsk, is also a major tourist destination in the summer, as millions of Poles and other European tourists flock to the beaches of the Baltic coastline.


title: Gdańsk

text: The city has some buildings surviving from the time of the Hanseatic League. Most tourist attractions are located along or near Ulica Długa ("Long Street") and Długi Targ ("Long Market"), a pedestrian thoroughfare surrounded by buildings reconstructed in historical (primarily during the 17th century) style and flanked at both ends by elaborate city gates. This part of the city is sometimes referred to as the Royal Route, since it was once the former path of processions for visiting Kings of Poland.


title: Gdańsk

text: Gdańsk has a number of historical churches, including St. Catherine's Church and St. Mary's Church ("Bazylika Mariacka"). This latter is a municipal church built during the 15th century, and is the largest brick church in the world.


title: Gdańsk

text: The city's 17th-century fortifications represent one of Poland's official national Historic Monuments ("Pomnik historii"), as designated on 16 September 1994 and tracked by the National Heritage Board of Poland.


title: Gdańsk

text: In 2011–2015 the Warsaw-Gdańsk-Gdynia railway route underwent a major upgrading costing $3 billion, partly funded by the European Investment Bank, including track replacement, realignment of curves and relocation of sections of track to allow speeds up to , modernization of stations, and installation of the most modern ETCS signalling system, which was completed in June 2015. In December 2014 new Alstom Pendolino high-speed trains were put into service between Gdańsk, Warsaw and Kraków reducing the rail travel time from Gdańsk to Warsaw to 2 hours 58 minutes, further reduced in December 2015 to 2 hours 39 minutes.


title: Gdańsk

text: Gdańsk is the starting point of the EuroVelo 9 cycling route which continues southward through Poland, then into the Czech Republic, Austria and Slovenia before ending at the Adriatic Sea in Pula, Croatia.


title: Gdańsk

text: Additionally, Gdańsk is part of the Rail-2-Sea project. This project's objective is to connect the city with the Romanian Black Sea port of Constanța with a long railway line passing through Poland, Slovakia, Hungary and Romania.


title: Gdańsk

text: There are many popular professional sports teams in the Gdańsk and Tricity area. Amateur sports are played by thousands of Gdańsk citizens and also in schools of all levels (elementary, secondary, university).


title: Gdańsk

text: The city's professional football club is Lechia Gdańsk. Founded in 1945, they play in the Ekstraklasa, Poland's top division. Their home stadium, Stadion Miejski, was one of the four Polish stadiums to host the UEFA Euro 2012 competition,as well as the host of the 2021 UEFA Europa League Final. Other notable football clubs are Gedania 1922 Gdańsk and SKS Stoczniowiec Gdańsk, which both played in the second tier in the past.


title: Gdańsk

text: The city's Hala Olivia was a venue for the official 2009 EuroBasket, and the Ergo Arena was one of the 2013 Men's European Volleyball Championship, 2014 FIVB Volleyball Men's World Championship and 2016 European Men's Handball Championship venues.


title: Gdańsk

text: Contemporary Gdańsk is one of the major centres of economic and administrative life in Poland. It has been the seat of a Polish central institution, the Polish Space Agency, several supra-regional branches of further central institutions such as the Energy Regulatory Office, the Office of Electronic Communications, the Civil Aviation Authority, the Office of Rail Transport and the Office of Competition and Consumer Protection, as well as the supra-regional (appellate-level) institutions of justice: the Court of Appeals, the Regional Public Prosecutor's Office, and the branch of the Institute of National Remembrance. As the capital of the Pomeranian Voivodeship it has been the seat of the Pomeranian Voivodeship Office, the Sejmik, and the Marshall's Office of the Pomeranian Voivodeship and other voivodeship-level institutions.


title: Gdańsk

text: Gdańsk Voivodeship was extended in 1999 to include most of former Słupsk Voivodeship, the western part of Elbląg Voivodeship and Chojnice County from Bydgoszcz Voivodeship to form the new Pomeranian Voivodeship.


title: Gdańsk

text: The area of the region was thus extended from and the population rose from 1,333,800 (1980) to 2,198,000 (2000). By 1998, Tricity constituted an absolute majority of the population; almost half of the inhabitants of the new region live in the centre.


title: Gdańsk

text: Legislative power in Gdańsk is vested in a unicameral Gdańsk City council (Rada Miasta), which comprises 34 members. Council members are elected directly every four years. Like most legislative bodies, the City Council divides itself into committees which have the oversight of various functions of the city government.


title: Gdańsk

text: Gdańsk is divided into 34 administrative divisions: 6 and 28 . Gdańsk include Chełm, Piecki-Migowo, Przymorze Wielkie, Śródmieście, Wrzeszcz Dolny, Wrzeszcz Górny.


title: Gdańsk

text: There are 15 higher schools including three universities. In 2001 there were 60,436 students, including 10,439 graduates.


title: Gdańsk

text: On 3 March 2022, Gdańsk City Council passed a unanimous resolution to terminate the cooperation with the Russian cities of Kaliningrad and Saint Petersburg as a response to the Russian invasion of Ukraine.


title: Gdańsk

text: The 1923 census conducted in the Free City of Danzig indicated that of all inhabitants, 95% were German, and 3% were Polish and Kashubian. The end of World War II is a significant break in continuity with regard to the inhabitants of Gdańsk.


title: Gdańsk

text: German citizens began to flee en masse as the Soviet Red Army advanced, composed of both spontaneous flights driven by rumors of Soviet atrocities, and organised evacuation starting in the summer of 1944 which continued into the spring of 1945. Approximately 1% (100,000) of the German civilian population residing east of the Oder–Neisse line perished in the fighting prior to the surrender in May 1945. German civilians were also sent as "reparations labour" to the Soviet Union.


title: Gdańsk

text: Poles from other parts of Poland replaced the former German-speaking population, with the first settlers arriving in March 1945. On 30 March 1945, the Gdańsk Voivodeship was established as the first administrative Polish unit in the Recovered Territories. As of 1 November 1945, around 93,029 Germans remained within the city limits. The locals of German descent who declared Polish nationality were permitted to remain, as of 1 January 1949 13,424 persons who had received Polish citizenship in a post-war "ethnic vetting" process lived in Gdańsk.


title: Air fryer

text: An air fryer is a small countertop convection oven designed to simulate deep frying without submerging the food in oil. A fan circulates hot air at high speed, producing a crisp layer via browning reactions such as the Maillard reaction. Some product reviewers find that regular convection ovens or convection toaster ovens produce better results, or say that air frying is essentially the same as convection baking.


title: Air fryer

text: Air fryers circulate hot air to cook food that would otherwise be submerged in oil. The air fryer's cooking chamber radiates heat from a heating element near the food, and a fan circulates hot air.


title: Air fryer

text: The original Philips Airfryer used radiant heat from a heating element just above the food and convection heat from a strong air stream flowing upwards through the open bottom of the food chamber, delivering heat from all sides, with a small volume of hot air forced to pass from the heater surface and over the food, with no idle air circulating as in a convection oven. A shaped guide directed the airflow over the bottom of the food. The technique was patented as "Rapid Air technology".


title: Air fryer

text: Traditional frying methods induce the Maillard reaction at temperatures of by completely submerging foods in hot oil, well above the boiling point of water. The air fryer works by coating the food in a thin layer of oil and circulating air at up to to apply sufficient heat to cause the reaction.


title: Air fryer

text: Most air fryers have temperature and timer adjustments that allow more precise cooking. Food is typically cooked in a basket that sits on a drip tray. The basket must be periodically agitated, either manually or by the fryer mechanism. Convection ovens and air fryers are similar in the way they cook food, but air fryers are generally smaller and give off less heat.


title: Air fryer

text: In 2010, Philips introduced the Airfryer brand of convection oven at a consumer electronics fair in Berlin. By 2018, the term "airfryer" was starting to be used generically.


title: Grenfell Tower fire

text: On 14 June 2017, a high-rise fire broke out in the 24-storey Grenfell Tower block of flats in North Kensington, West London, at 00:54 BST. 72 people died, including two who later died in hospital, with more than 70 others being injured and 223 people escaping. It was the deadliest structural fire in the United Kingdom since the 1988 "Piper Alpha" oil-platform disaster and the worst UK residential fire since World War II.


title: Grenfell Tower fire

text: The fire was started by an electrical fault in a refrigerator on the fourth floor. It spread rapidly up the building's exterior, bringing fire and smoke to all the residential floors. This was due to the building's new cladding and the external insulation, since the air gap between them enabled the stack effect. The fire burned for about 60 hours before finally being extinguished. More than 250 London Fire Brigade firefighters and 70 fire engines from stations across London were involved in efforts to control the fire and rescue residents. More than 100 London Ambulance Service crews on at least 20 ambulances attended the scene, joined by specialist paramedics from the Ambulance Service's Hazardous Area Response Team. The Metropolitan Police and London's Air Ambulance also assisted the rescue effort.


title: Grenfell Tower fire

text: The Grenfell Tower Inquiry began on 14 September 2017 to investigate the causes of the fire and other related issues. Findings from the first report of the inquiry were released in October 2019 and addressed the events of the night. It affirmed that the building's exterior did not comply with regulations and was the central reason why the fire spread, and that the fire service were too late in advising residents to evacuate. A second phase to investigate the broader causes began on the third anniversary in 2020.


title: Grenfell Tower fire

text: Grenfell Tower was part of the Lancaster West Estate, a council housing complex in North Kensington. The 24-storey tower block was designed in 1967 in the Brutalist style of the era by Clifford Wearden and Associates, and the Kensington and Chelsea London Borough Council approved its construction in 1970. The building was constructed by contractors A E Symes of Leyton from 1972 to 1974.


title: Grenfell Tower fire

text: The tall building contained 120 one-bedroom and two-bedroom flats. The upper 20 (of 24) storeys were residential floors, with each having a communal lobby and six dwellings, with ten bedrooms among them. The lower four storeys were originally used for non-residential purposes. Later, two lower floors were converted to residential use, bringing the total to 129 apartments, housing up to 600 people. The original lead architect for the building, Nigel Whitbread, said in 2016 that the tower had been designed with attention to strength following the 1968 Ronan Point disaster and "from what I can see could last another hundred years".


title: Grenfell Tower fire

text: Like many other tower blocks in the UK, Grenfell Tower was designed to be operated under a "stay put policy" in the event of fire. The idea was that if a fire broke out in one flat, thick walls and fire doors would contain the fire long enough for the fire service to bring it under control. Only those in the affected dwelling would be expected to evacuate. The building was designed under the assumption that a full evacuation would never be necessary. There was no centrally activated fire alarm and only a single central staircase. Unlike in many other countries, UK regulations do not require a second. In 2010, a fire broke out in a lobby and was quickly extinguished.


title: Grenfell Tower fire

text: Until 1996, Kensington and Chelsea London Borough Council managed its council housing directly. In 1996, the council created Kensington and Chelsea TMO (KCTMO), a tenant management organization which would manage its council housing stock. KCTMO had a board comprising eight residents (tenants or leaseholders), four council-appointed members and three independent members. The tower was built as council housing, but fourteen of the flats had been bought under the Right to Buy policy. These were occupied by leaseholders, or were privately rented out by them on the open market.


title: Grenfell Tower fire

text: Grenfell Tower underwent a major renovation, announced in 2012 and conducted over 2015–2016. The tower received new windows, a water-based heating system for individual flats and new aluminium composite rain screen cladding. According to the application, the purpose of the cladding was to improve heating and energy efficiency, and external appearance. Mark Harris, of Harley Facades, said, "from a selfish point of view", his company's preference was to use (cheaper) aluminium composite material.


title: Grenfell Tower fire

text: Two types of cladding were used: Arconic's Reynobond PE, which consists of two -coated aluminium sheets that are fusion bonded to both sides of a polyethylene core; and Reynolux aluminium sheets. Beneath these, and fixed to the outside of the walls of the flats, was Celotex RS5000 PIR thermal insulation. An alternative cladding with better fire resistance was refused due to cost.


title: Grenfell Tower fire

text: The original contractor, Leadbitter, had been dropped by KCTMO because their price of £11.278 million was £1.6 million higher than the proposed budget. The contract was put out to competitive tender and won by Rydon, whose bid was £2.5 million less than Leadbitter's. Rydon carried out the refurbishment for £8.7 million, with Artelia on contract administration and Max Fordham as specialist mechanical and electrical consultants. The cladding was fitted by Harley Facades of Crowborough, East Sussex, at a cost of £2.6 million.


title: Grenfell Tower fire

text: Residents had expressed significant safety concerns before the fire. Twelve years earlier, a report had criticised the tower's emergency lighting. The Grenfell Action Group (GAG) ran a blog in which it highlighted major safety problems, criticizing the council and KCTMO for neglecting fire safety and building maintenance.


title: Grenfell Tower fire

text: In 2013, the group published a 2012 fire risk assessment by a KCTMO Health and Safety Officer which recorded safety concerns. Firefighting equipment at the tower had not been checked for up to four years; on-site fire extinguishers had expired, and some had the word "condemned" written on them because they were so old. GAG documented its attempts to contact KCTMO management; they also alerted the council's cabinet member for Housing and Property but said they never received a reply. In 2013 the council threatened one of the bloggers with legal action, saying that their posts amounted to "defamation and harassment". Two women living in Grenfell Tower, Mariem Elgwahry and Nadia Choucair, were threatened with legal action by KCTMO after they campaigned for improved fire safety. They later died in the fire, at the age of 27 and 33.


title: Grenfell Tower fire

text: In January 2016, GAG warned that people might be trapped in the building if a fire broke out, pointing out that the building had only one entrance and exit, and corridors that had been allowed to fill with rubbish, such as old mattresses. GAG frequently cited other fires in tower blocks when it warned of the hazards at Grenfell. In November 2016, GAG characterized KCTMO as an "evil, unprincipled, mini-mafia" and accused the council of ignoring health and safety laws. GAG suggested that "only a catastrophic event will expose the ineptitude and incompetence of [KCTMO]", adding, "[We] predict that it won't be long before the words of this blog come back to haunt the KCTMO management and we will do everything in our power to ensure that those in authority know how long and how appallingly our landlord has ignored their responsibility to ensure the heath [sic] and safety of their tenants and leaseholders. They can't say that they haven't been warned!" The Grenfell Tower Leaseholders' Association had also raised concerns about exposed gas pipes in the months before the fire. As with the majority of tower blocks in the UK, Grenfell Tower did not have fire sprinklers.


title: Grenfell Tower fire

text: Meanwhile, in June 2016, an independent assessor had highlighted 40 serious issues with fire safety at Grenfell Tower and recommended action to be taken within weeks. In October, the assessor asked the KCTMO why there had been no action taken for more than 20 issues in the June report. In November 2016, the London Fire and Emergency Planning Authority served a fire deficiency notice, listing many fire safety issues at Grenfell Tower that required action from KCTMO by May 2017. Areas of concern identified included fire doors, the smoke venting system and the firefighters' lift controls.


title: Grenfell Tower fire

text: One of the earliest fires that involved cladding materials was the 1973 Summerland disaster on the Isle of Man, which caused 50 deaths. Part of the reason why the fire spread rapidly through the leisure centre was the acrylic sheeting on the exterior of the building. In the 1991 Knowsley Heights fire, fire spread up the entire height of an 11-storey building due to its exterior cladding, though it did not enter the interior and nobody was injured. In 2009, external composite panels also played a role in the spread of the Lakanal House fire in Southwark. An article in "The Guardian" three days after the Grenfell Tower fire described it as a "tragedy foretold", highlighting that there had been previous cladding fires such as the 2015 fire at The Marina Torch in Dubai, United Arab Emirates.


title: Grenfell Tower fire

text: In 2016, a non-fatal fire at a Shepherd's Bush tower block spread to six floors via flammable external cladding. In May 2017, the London Fire Brigade (LFB) warned all 33 London councils to review the use of panels and "take appropriate action to mitigate the fire risk".


title: Grenfell Tower fire

text: The fire started in the early hours of Wednesday 14 June 2017 at around 00:50 BST (UTC+1), when a fridge-freezer caught fire in Flat 16, on the fourth floor. The flat's resident, Behailu Kebede, was woken by a smoke alarm. He alerted his lodgers and neighbours after entering the kitchen and discovering the fridge freezer smoking, and then called the LFB at 00:54. The first two fire engines ("pumps") arrived six minutes later. The initial incident commander said that the fire was visible at this point as a "glow" in the window. A further two pumps were also dispatched. Any residents of the tower who called the fire service were told to remain in their flat unless it was affected, which is the standard policy for high-rise fires, as each flat should be fireproofed from its neighbours. Also due to this policy, the building had no central fire alarm.


title: Grenfell Tower fire

text: After most of the firefighters entered the building, a bridgehead (internal base of operations) was set up on the second floor, connecting hoses to the dry riser. They first entered Flat 16 at 01:07. It was a further seven minutes before they began tackling the kitchen blaze. At approximately 01:08, the fire began to penetrate the window frame. Within a few minutes, it was setting the surrounding cladding panels on fire. Observing this, the incident commander requested another two pumps and an aerial appliance at 01:13, which also triggered the dispatch of more senior officers, a fire investigation unit and two command vehicles. Another firefighter was asked to try to prevent it spreading with a water jet, though this jet could not reach higher than the fourth floor, and due to fears of causing a dangerous build-up of steam on the inside, it was not aimed directly at the window.


title: Grenfell Tower fire

text: By the time the firefighters began extinguishing the kitchen fire, a column of flames was quickly advancing up the side of the building. At 01:15, a firefighter discovered smoke in Flat 26 (directly above Flat 16), another discovered residents who had fled smoke on the fifth and sixth floors, and outside large quantities of debris began falling from the burning façade. The flames spread up the side at a "terrifying rate". Attempts to fight the fire with an external jet were unsuccessful, as it was mostly burning behind the waterproof rainscreen. By 01:30, a rising column of flames had reached the roof and the fire grew out of control. The fire on the eastern exterior spread sideways and brought smoke and flames into multiple flats.


title: Grenfell Tower fire

text: By 01:18, 34 of 293 residents had escaped. The busiest phase of evacuations was between 01:18 and 01:38, when 110 escaped, with many being woken up by their smoke alarms when smoke entered their flat. Due to Ramadan, many observing Muslim residents were awake for the pre-dawn meal of "suhur", which enabled them to alert neighbours.


title: Grenfell Tower fire

text: LFB rapidly escalated its response during this time period. The number of pumps in attendance was raised from six to eight at 01:19, with a specialist fire-rescue unit, bulk breathing apparatus carrier and damage control unit being sent too. Pumps were made up to 10 at 01:24, then to 15 at 01:27 along with a second aerial platform. Two minutes later, pumps were made 20 and two more fire-rescue units were mobilized, and pumps were made up to 25 at 01:35, also triggering the dispatch of an Assistant Commissioner. Dany Cotton, the Commissioner of the London Fire Brigade, was also called out and began driving to the scene from her home in Kent. The Metropolitan Police Service (MPS) were called at 01:24 to manage the gathering crowd outside. Five minutes later, the London Ambulance Service were also called.


title: Grenfell Tower fire

text: Due to fire doors not closing and sealing properly, smoke began to spread from affected flats into the lobbies. By 01:33, LFB were receiving calls from residents who reported being trapped in their flats. At some point between 01:30 and 01:40, smoke began to enter the stairwell. The Inquiry later estimated that despite this, the stairs were still passable for over half an hour. Evacuation rates slowed, with 20 escaping between 01:38 and 01:58. More than half of those still trapped at 01:58 were killed, while 48 were rescued between 01:58 and 03:58. The fire continued to spread sideways on the exterior, and by 01:42 had reached the north side.


title: Grenfell Tower fire

text: LFB call handlers collected information from trapped residents and this was relayed to the LFB's command unit that was parked outside. Communicating through radio proved difficult, due to noise, the sheer volume of talk and possibly the concrete building structure. Instead, details of trapped residents were written on slips of paper and ferried by runners from the command unit to the bridgehead on the second floor. At the bridgehead, incoming firefighters were assigned flats to go to and briefed on whom they would need to rescue. They donned breathing apparatus and headed to the flat to search for its residents.


title: Grenfell Tower fire

text: The firefighters encountered thick smoke, zero visibility and extreme heat when they climbed above the fourth floor. Furthermore, some residents had moved location to escape the smoke. Three firefighters who went to rescue a 12-year-old girl on the 20th floor were unable to find her. Unknown to them, she had moved up to a flat on the 23rd floor, was on the phone to a control operator who had no means of knowing what the firefighters were doing, and later died in this location. Another two firefighters were sent to a flat on the 14th floor with a single resident, only to find 8 people (four of them eventually escaped).


title: Grenfell Tower fire

text: As the fire rapidly spread around the building, witnesses on the ground reported seeing trapped residents switching the lights in their flats on and off or waving from windows to attract help, some holding children. Eyewitnesses reported seeing some people jumping to their deaths, and four victims were later found to have died from "injuries consistent with falling from a height". These deaths were classed as 'suicides', despite being a direct consequence of the fire. At least one person used knotted blankets to make a rope and escape from the burning building. Frequent explosions that were reported to be from gas lines in the building were heard.


title: Grenfell Tower fire

text: Outside operations were hindered by falling debris, including burning pieces of cladding. Due to this danger, the police moved crowds away from the building as a safety precaution. The MPS Territorial Support Group was present; besides being a specialist unit for public order policing, they provided riot shields to protect firefighters from falling debris.


title: Grenfell Tower fire

text: Shortly after 02:00, a major incident was declared and the number of fire engines was raised from 25 to 40, the number of fire-rescue units increased to 10, command vehicles to six, aerial platforms to four, and operational support units to two. Over the course of the operation, 250 firefighters attempted to control the blaze, with more than 100 firefighters inside the building at a given time. Assistant Commissioner Andrew Roe assumed direct command of firefighting operations for the next 11 hours. Rather than command the operations directly, Commissioner Cotton served as a Monitoring Officer, overseeing Roe and providing moral support to firefighters. She admitted that LFB had broken their own safety protocols by entering a large building without knowing whether it was in danger of structural collapse. It was not until the following afternoon that structural engineers were able to assess the structure and determine that it was not in danger of collapse.


title: Grenfell Tower fire

text: By 02:20, the level of smoke in the stairwell constituted a threat to life, although some survivors did escape beyond then. At 02:47 the "stay put" policy, advising those residents in areas unaffected by the blaze to remain there, was abandoned in favour of general evacuation. After this point only 36 further residents were able to escape. Experts on the subsequent inquiry into the disaster later said that the "stay put" policy should have been discarded an hour and twenty minutes before it eventually was.


title: Grenfell Tower fire

text: By sunrise, firefighters were still busy fighting the fire and attempting rescues on the inside. At 04:14, police addressed the large crowd of onlookers and urgently instructed them to contact anyone they knew who was trapped in the building—if they were able to reach them via phone or Twitter—to tell them they must try to self-evacuate and not wait for the fire brigade. By 04:44, all sides of the building had been affected.


title: Grenfell Tower fire

text: Only two further rescues took place, with one resident being rescued at 06:05 and the last being rescued at 08:07. Firefighters rescued all remaining residents up to the 10th floor and all but two up to the 12th floor, but none got higher than the 20th floor during this time; only two people escaped from the highest two floors.


title: Grenfell Tower fire

text: At a news conference in the afternoon of 14 June, LFB reported firefighters had rescued 65 people from the building and reached all 24 floors. Seventy-four people were confirmed by the NHS to be in six hospitals across London with 20 of them in critical care.


title: Grenfell Tower fire

text: The fire continued to burn on the tower's upper floors. It was not brought under control until 01:14 on 15 June and firefighters were still damping down pockets of fire when the Brigade issued an update on 16 June. The fire brigade also used a drone to inspect the building and search for casualties. The fire was declared extinguished on the evening of 16 June.


title: Grenfell Tower fire

text: In the immediate aftermath of the fire, a number of unsubstantiated reports about casualties circulated online, which were to later be debunked, including that the government had covered up details of the fire and babies' miraculous survival stories. A later investigation by the BBC's "Newsnight" programme found no evidence that these survival accounts were credible: neither the Metropolitan Police, London Ambulance Service nor any A&E departments were able to find any record of this happening.


title: Grenfell Tower fire

text: The fire caused 72 deaths, including one who died in the hospital a day later and another who died in January 2018. The latter occurred after an official death toll was announced by police in November 2017. The incident ranks as the deadliest structural fire in the United Kingdom since the 1988 Piper Alpha disaster and the worst UK residential fire since the Second World War.


title: Grenfell Tower fire

text: The dead included many children, five of whom were students at the nearby Kensington Aldridge Academy. The youngest of those known killed, Leena Belkadi, was 6 months old. One victim died in hospital on 15 June 2017 due to inhalation of fire fumes. Additionally, one then-pregnant survivor lost her baby through stillbirth as a result of the fire.


title: Grenfell Tower fire

text: Survivors came from 106 of the tower's 129 flats; eighteen people among the occupants of these flats were reported as dead or missing presumed dead, whereas most of those killed were said to have been in the remaining 23 flats between the 11th and 23rd floors. Some people from lower floors may have tried to move up the building, and it is thought a number of people may have ended up in one flat.


title: Grenfell Tower fire

text: Police examined the remains of Grenfell Tower and used "every imaginable source" of information "from government agencies to fast food companies" to identify casualties. Their analysis of CCTV evidence concluded that 223 people (of 293 present) had escaped. This investigation took five months, with only 12 fatalities being identified on the actual day of the fire. By the following week, police had estimated that 80 people had died. This was the most widely quoted estimate in the media for several months. Some victims were identified from 26 calls to 999 made from inside the 23 flats.


title: Grenfell Tower fire

text: On 19 September 2017, Metropolitan Police Commander Stuart Cundy suggested that the number of dead could be lower than 80 because eight people were being investigated for making fraudulent financial claims for non-existent victims. By 1 June 2018, this had led to five people being convicted of fraud.


title: Grenfell Tower fire

text: Obstacles to identifying fatalities included the fact there was no formal register of who was in the building, and the number of undocumented subtenants, migrants and asylum seekers who were believed to have been living there. Mayor Sadiq Khan called for an amnesty to ensure that people with pertinent information could come forward.


title: Grenfell Tower fire

text: The first Coroner's Inquests opened on 23 August 2017 and all other inquests were opened by 23 November 2017.


title: Grenfell Tower fire

text: In the aftermath of the fire, members of the local community, including a residents' group called Grenfell United, stated that the official figures were far short of existing estimates, with some believing that the death toll was "in hundreds". Ten days after the fire, only 18 deaths had yet been officially recorded, compared to the estimate of 80 and the eventual figure of 72. Rumours that the toll was higher than official figures persisted after the official figures were confirmed.


title: Grenfell Tower fire

text: Beyond physical injury, the fire was a traumatic event which had a psychological impact on residents, emergency service workers and the public at large.


title: Grenfell Tower fire

text: On 26 July 2017, at the fourth public meeting of the Grenfell Response Team, a local volunteer reported that there had been at least 20 suicide attempts in north Kensington since the fire, one of which had been completed. The mental health of many survivors was damaged.


title: Grenfell Tower fire

text: LFB Commissioner Dany Cotton defended the heroism of emergency service workers who themselves were affected by trauma. An on-call counsellor was made available. Around 80 firefighters and Met Police officers were reported to be suffering from their experiences. Cotton told LBC Radio that she too was undergoing counselling.


title: Grenfell Tower fire

text: An extra four full-time counsellors were employed (reversing previous staff reductions) and 60 volunteer counsellors were brought in. All firefighters who attended Grenfell were given a psychological health check. The BBC reported that LFB used its reserve budget to bring counselling staff back to 2008 levels.


title: Grenfell Tower fire

text: In July 2017, NHS England issued an open letter to GPs giving advice on symptoms for mental health conditions such as post-traumatic stress disorder (PTSD) that those affected by this fire (or recent terrorism) may be experiencing. It is estimated that 67% of people caught up in the fire, lost relatives, or were rescued or evacuated from the tower, need treatment for PTSD. Further, between 26% and 48% of people living nearby who were not evacuated but witnessed the fire have PTSD. It is unclear how far this indicated reaction to the fire and how far previously existing psychiatric conditions were being uncovered.


title: Grenfell Tower fire

text: The Metropolitan Police Service assigned 250 detectives to the fire, placing additional workload and personal stress on a force that was also investigating recent terrorist incidents, including the London Bridge and Finsbury Park attacks.


title: Grenfell Tower fire

text: Psychologists worked at Kensington Aldridge Academy to support students returning to the original site. Measures have been taken to protect student welfare, such as shielding classroom windows overlooking the tower.


title: Grenfell Tower fire

text: On 21 September 2018, the coroner, Fiona Wilcox, expressed concern for the long-term physical health of victims and emergency service workers exposed to smoke and dust inhaled during the fire and subsequent cleanup. Those affected could be at increased risk of conditions such as cancer, asbestosis, COPD and asthma. The tower is known to have contained asbestos and other toxins. In her letter to NHS chief executive Simon Stevens, Wilcox notes that firefighters involved in the September 11 attacks suffered significant health problems from smoke inhalation. She asked for a physical health screening programme to be established to help prevent future deaths.


title: Grenfell Tower fire

text: Public Health England have been monitoring the quality of the air around the derelict tower. In a March 2019 report, they stated that "the risk to public health from air pollution remains low." While the fire itself released many toxic chemicals, they were quickly dispersed in the wind. There has not been a full assessment of the risk posed by soil contamination. Also in March 2019, an independent study led by Professor Anna Stec reported in the journal Chemosphere that research had uncovered "significant environmental contamination" in the soil and buildings around the local area, including significant concentrations of benzene, benzo(a)pyrene, phosphorus and polycyclic aromatic hydrocarbons. Chemicals in the soil are unlikely to seep into the air, but could be uncovered if the soil is disturbed. Stec said her findings showed "the need for further in-depth, independent analysis to quantify any risks to residents".


title: Grenfell Tower fire

text: Grenfell Tower was insured by Protector Forsikring ASA for £20 million, but the direct costs of the fire are likely to be substantially higher. According to "The Times", the financial impact of the fire could reach as high as £1 billion due to a combination of litigation, compensation for deaths and injuries, rehousing and rehabilitation, the cost of demolition and rebuilding and the possibility that other tower blocks may have to be improved or evacuated.


title: Grenfell Tower fire

text: Councils said the government is not releasing funds to increase fire safety in many other tower blocks after the Grenfell fire, although they promised lack of finance would not prevent essential work. The government is not paying to put sprinklers into older tall buildings though sprinklers are required in new buildings over 30 metres tall.


title: Grenfell Tower fire

text: In the 22 November 2017 Budget, Chancellor Philip Hammond announced that an extra £28 million was being provided to help victims. He asked that local authorities without the means to make buildings safe should contact central government. Of the fire he said, "This tragedy should never have happened, and we must ensure that nothing like it ever happens again."


title: Grenfell Tower fire

text: On 4 January 2018, BBC News reported the Met Police were asking the Home Office to pay for the investigation, which was one of the largest, most complex and most expensive in its history. A figure of £38 million was quoted.


title: Grenfell Tower fire

text: On 9 May 2019, Housing Secretary James Brokenshire announced the £200m cost of replacing cladding on private tower blocks would be paid for by the Government, reversing the position of leaving costs to owners.


title: Grenfell Tower fire

text: A total of 151 homes were destroyed in the tower and surrounding area. People from surrounding buildings were evacuated due to concerns that the tower might collapse.


title: Grenfell Tower fire

text: The fire also severely affected three low-rise "finger blocks" adjoining Grenfell Tower. Their residents were evacuated due to the fire. The blocks, Barandon Walk, Testerton Walk and Hurstway Walk, also lost access to hot water as they shared a boiler beneath Grenfell Tower that was destroyed in the fire.


title: Grenfell Tower fire

text: It was initially reported that the fire had been started by a faulty refrigerator. Police confirmed on 23 June that a faulty fridge-freezer had initially started the fire and named the model as a FF175BP fridge-freezer produced under the Hotpoint brand by Indesit. Owners of the types FF175BP and FF175BG were urged to register their appliance with the manufacturer to receive any updates. Sixty-four thousand of these models were made between March 2006 and July 2009, after which the model was discontinued. It is unknown how many are still in use.


title: Grenfell Tower fire

text: The Department for Business, Energy and Industrial Strategy (BEIS) commissioned a product safety investigation into the Hotpoint FF175B fridge-freezer. Independent experts examined the remains of the appliance recovered from Grenfell and exemplar models of the same type. They concluded that the design met all legal safety requirements, and there was no need to issue a recall of the model. Consumer group Consumers' Association complained that the legal requirements were inadequate.


title: Grenfell Tower fire

text: Tenants had repeatedly complained about electrical power surges causing appliances to smoke and such a surge may have set the fridge-freezer on fire. The local authority knew about complaints and had paid tenants compensation for damaged appliances. Nonetheless, the surges continued. Judith Blakeman, a local Labour councillor, said the surges affected many appliances including fridges. Blakeman maintains that the cause of the surges was never solved.


title: Grenfell Tower fire

text: On 27 November 2018, evidence given to the Grenfell Tower inquiry by electrical investigating engineer J. Duncan Glover suggested that in Flat 16 the fridge-freezer compressor relay wiring was not tightly fitted. In his view, this probably created additional electrical resistance leading to overheating and igniting the outer plastic insulation of the wire at 90 °C (200 °F). Glover described the state of the fusebox following a short circuit to the compressor. During questioning, he compared US and UK safety standards, noting that US regulations require a steel back to the fridge to help contain a fire, whereas UK fridges were allowed to have only a plastic backing.


title: Grenfell Tower fire

text: Both the aluminium-polyethylene cladding and the PIR insulation plates failed fire safety tests conducted after the fire, according to the police.


title: Grenfell Tower fire

text: Earlier in 2014, safety experts had cautioned that the planned insulation was only suitable for use with non-combustible cladding. "The Guardian" saw a certificate from the building inspectors' organisation, Local Authority Building Control (LABC), which stated that the chosen insulation for the refit should only be used on tall buildings with fibre cement panels, which do not burn. Combustible panels with polyethylene were put up on top of insulation known as Celotex RS5000, made from polyisocyanurate, which burns when heated, giving off toxic cyanide fumes.


title: Grenfell Tower fire

text: Despite the above, the Royal Borough of Kensington and Chelsea certified the Grenfell tower building work as allegedly conforming to "the relevant provisions". Council building inspectors visited the site 16 times from August 2014 to July 2016. Kooltherm, a phenolic insulation, was also used on Grenfell. Kooltherm was never tested with polyethylene core aluminium panels according to the manufacturer. The manufacturer, Kingspan, "would be very surprised if such a system ... would ever pass the appropriate British Standard 8414 large-scale test". Kooltherm's LABC certificate states phenolic products, "do not meet the limited combustibility requirements" of building regulations.<ref name="Guardian13/7/2017"></ref>


title: Grenfell Tower fire

text: The combustible materials used on Grenfell Tower were considerably cheaper than non-combustible alternatives would have been. There appear to have been intense cost pressures over the Grenfell refurbishment. In June 2017, it was stated the project team chose cheaper cladding that saved £293,368, after the Kensington and Chelsea Tenant Management Organisation mentioned in an email the need for "good costs for Cllr Feilding-Mellen [the council's former deputy leader]".


title: Grenfell Tower fire

text: A building control officer from the Royal Borough of Kensington and Chelsea reportedly passed the cladding on Grenfell Tower on 15 May 2015, though there was a nationwide warning that the combustible insulation used should only be used with cladding that does not burn.


title: Grenfell Tower fire

text: Fire safety experts have said that the building's new external cladding was a possible cause of the rapid spread of the fire. Experts said the gap between the cladding and the insulation worked like a chimney to spread the fire. The cladding could be seen burning and melting, causing additional speculation that it was not made of fire-resistant material. One resident said: "The whole one side of the building was on fire. The cladding went up like a matchstick."


title: Grenfell Tower fire

text: Concerns about the dangers of external cladding were raised years before, following a fire in 1991 at flats in Knowsley Heights, Merseyside. Recent major high-rise fires that have involved flammable cladding are listed below.


title: Grenfell Tower fire

text: Records show that a contractor had been paid £2.6 million to install an "ACM rainscreen over-clad" during the recent refurbishment at Grenfell Tower. ACM stands for "aluminium composite material", also known as a sandwich panel, the combustibility of which depends on the choice of insulation core material.


title: Grenfell Tower fire

text: One of the products used was Arconic's Reynobond, which is available with different types of core material—polyethylene, as reportedly used in Grenfell Tower (Reynobond PE), or a more fire-resistant material (Reynobond FR). The Reynobond cladding reportedly cost £24 per square metre (£20 per sq. yd.) for the fire-retardant version, and £22 (£18) for the combustible version.


title: Grenfell Tower fire

text: According to Arconic's website and brochure for the mainland European market at the time of the fire, the Reynobond PE cladding used was suitable only for buildings 10 metres (30') or less tall; the fire-retardant Reynobond FR was suitable for buildings up to 30 metres (100') tall; and above the latter height, such as the upper parts of Grenfell Tower, the non-combustible A2 version was supposed to be used ("As soon as the building is higher than the firefighters' ladders, it has to be conceived with an incombustible material"). After the fire, Arconic stopped sales of Reynobond PE worldwide for tower blocks.


title: Grenfell Tower fire

text: Similar cladding containing highly flammable insulation material is believed to have been installed on thousands of other high-rise buildings in countries including Britain, France, the UAE and Australia. Advice published by the Centre for Window and Cladding Technology is that where such materials are used in buildings over 18m, the fire performance of the cladding system as a whole must be proven by testing.


title: Grenfell Tower fire

text: In September 2014, a building regulations notice for the re-cladding work was submitted to the authority and marked with a status of "Completed—not approved". The use of a "Building Notice" building control application is used to remove the need to submit detailed plans and proposals to a building control inspector in advance, where the works performed will be approved by the inspector during the course of their construction. Building inspector Geoff Wilkinson remarked that this type of application is "wholly inappropriate for large complex buildings and should only be used on small, simple domestic buildings".


title: Grenfell Tower fire

text: On 18 June, Chancellor of the Exchequer Philip Hammond stated that the cladding used on Grenfell Tower was banned in the United Kingdom. Grenfell Tower was inspected 16 times while the cladding was being put on but none of these inspections noticed that materials effectively banned in tall buildings were being used. Judith Blakeman, local Labour councillor questioned the competence of the inspectors. Blakeman, representing the Grenfell residents, said, "This raises the question of whether the building regulations officers were sufficiently competent and did they know what they were looking at. It also begs a question about what they were actually shown. Was anything concealed from them?"


title: Grenfell Tower fire

text: The Department for Communities and Local Government stated that cladding with a polyethylene core "would be non-compliant with current Building Regulations guidance. This material should not be used as cladding on buildings over in height." On 31 July 2017, the Department released results of fire safety testing on the cladding panels used at Grenfell Tower, which were carried out by the Building Research Establishment and assigned the polyethylene filling a category three rating, designating a total lack of flame retardant properties.


title: Grenfell Tower fire

text: Fire safety experts said the tests the government is doing on cladding only are insufficient, as the whole unit of cladding and insulation should be tested including fire stops. Fire safety experts maintain further that the testing lacks transparency, as the government has not described what tests are being carried out.


title: Grenfell Tower fire

text: According to US-based Arconic, the polyethylene version of the material is banned in the United States for use in buildings exceeding in height, because of the risk of spreading fire and smoke. NPR subsequently stated that nearly all jurisdictions in the US (except three states and the District of Columbia) have enacted the International Building Code (IBC) requirement that external wall assemblies (cladding, insulation, and wall) on high-rise buildings with combustible components must pass a rigorous real-world simulation test promulgated by the National Fire Protection Association under the name NFPA 285.


title: Grenfell Tower fire

text: To perform the test, the entire planned assembly is constructed on a standardised test rig two storeys tall, with a window opening in the middle, and is continuously ignited with gas burners from two different angles for 30 minutes. The assembly must satisfy numerous performance criteria to pass, including a requirement that flames cannot spread more than vertically from the top of the window opening or horizontally.


title: Grenfell Tower fire

text: A single NFPA 285 test can cost over US$30,000, and it certifies only a particular assembly (i.e., a particular combination of parts from specific manufacturers as they are currently fabricated), meaning that any change to any part used for any reason requires a new test. As of mid-2017 ACM cladding with a polyethylene core had not been able to pass the NFPA 285 test, and thus had been effectively banned on US high-rise buildings for decades. The UK does not mandate the use of such realistic simulations and allows its own similar full-scale tests to be bypassed as long as "the wall assembly components, when tested individually, pass small-scale combustibility tests."


title: Grenfell Tower fire

text: The refurbishment also used an insulation foam product named Celotex RS5000, installed behind the cladding. Police said this insulation proved "more flammable than the cladding".


title: Grenfell Tower fire

text: According to its datasheet, the polyisocyanurate (PIR) product—charred pieces of which littered the area around Grenfell Tower after the fire—"will burn if exposed to a fire of sufficient heat and intensity". PIR insulation foams "will, when ignited, burn rapidly and produce intense heat, dense smoke and gases which are irritating, flammable and/or toxic", among them carbon monoxide and hydrogen cyanide. The fire toxicity of polyisocyanurate foams has been well understood for some time.


title: Grenfell Tower fire

text: At least three survivors were treated for cyanide poisoning. Simultaneous exposure to carbon monoxide and hydrogen cyanide is more lethal than exposure to the gases separately.


title: Grenfell Tower fire

text: Celotex's Rainscreen Compliance Guide, when specifying Celotex RS5000 in buildings above , sets out the conditions under which the product was tested and for which it has been certified as meeting the required fire safety standards. These include the use of (non-combustible) fibre cement rainscreen panels, ventilated horizontal fire breaks at each floor slab edge and vertical non-ventilated fire breaks. It states that any changes from the tested configuration "will need to be considered by the building designer".


title: Grenfell Tower fire

text: It has been asserted that cavity barriers intended to prevent the spread of fire in the gap between the facade and the building (the chimney effect) were of insufficient size and, in some cases, incorrectly installed, facilitating the spread of fire.


title: Grenfell Tower fire

text: It has been asserted that windows and their surrounds installed as part of the refurbishment were less fire resistant than those they replaced due to the materials used and that the windows were of insufficient size necessitating larger surrounds. This would facilitate the spread of fire between the interior and exterior of the building.


title: Grenfell Tower fire

text: Criticism of the response to the fire primarily consisted of condemnation of issues with the emergency response and fire safety regulation practices in the UK at the time. Broader political criticism was also directed at British society, including condemnation of the response by governmental bodies and UK politicians, social divisions, deregulation issues, and poor transparency overall.


title: Grenfell Tower fire

text: In the days after the fire, UK local authorities undertook reviews of fire safety in their residential tower blocks. Building regulations also came under review in the light of the fire due to concerns with the rules and their enforcement.


title: Grenfell Tower fire

text: On 30 August 2017, the Department for Communities and Local Government published the terms of reference for the Independent Review of Building Regulations and Fire Safety. This independent review was led by Dame Judith Hackitt, who is a senior engineer and civil servant with experience as the Chair of the Health and Safety Executive. The review reported to both DCLG head, James Brokenshire (Sajid Javid at the time the report was commissioned) and Home Secretary, Sajid Javid (Amber Rudd at the time the report was commissioned). The two main aims of the review are firstly to develop improved building regulations for the future, with a focus on residential high-rise blocks, and secondly to provide reassurance to residents that their homes are safe.


title: Grenfell Tower fire

text: The Department for Communities and Local Government (DCLG) commissioned tests on how various cladding systems fared in a fire. Seven combinations were tested, and six deemed dangerous. It reported in August 2017 that there were 228 buildings in the United Kingdom cladded using these methods. There are no existing buildings in the UK using the one combination deemed safe, but it could be used to reclad all the buildings that are currently using the other combinations. These findings will be used to help revise the Building Regulations.


title: Grenfell Tower fire

text: On 18 December 2017, Hackitt published her initial report. She described the entire building regulatory system as "not fit for purpose" and made interim recommendations for significant change. The final report was published on 17 May 2018, outlining a number of key failings and recommendations. The report did not recommend a ban on the use of combustible cladding on high rise buildings and Hackitt did say that she would support the government if it was to attempt to legislate a ban. Recommendations will be reconsidered after the conclusion of the public inquiry. The government is consulting on a possible ban on combustible materials. It is unclear if this applies only to cladding or to insulation as well.


title: Grenfell Tower fire

text: In October 2018, the government announced plans to ban flammable cladding on newly built buildings that were over the height, as well as for those of certain types such as schools, care homes and student housing. The Fire Brigades Union have argued that it should be entirely banned, and that a ban should also apply to existing buildings.


title: Grenfell Tower fire

text: By November 2019, the Government had identified 446 residential and publicly owned buildings in England over 18 metres in height with ACM cladding of the kind used on Grenfell Tower that were unlikely to meet Building Regulations and had pledged £600m towards paying for remediation. However, as investigations arising from the Grenfell disaster proceeded, along with the Barking Riverside fire in June 2019 and the Bolton Cube fire in November 2019, it became clear that far more buildings in the UK either used materials that did not meet safety standards or were otherwise not constructed in accordance with building regulations. By June 2020, around 2,000 high-risk buildings had been identified over 18m tall in England alone; a further 9,600 high-rise buildings thought to have combustible cladding; and 100,000 between 11 and 18 metres whose status was as yet unknown. 2019 saw a collapse in confidence in the safety of blocks of flats among mortgage lenders and insurers, leading to the freezing of a substantial section of the UK housing market. By February 2021, the government had pledged somewhat over £5bn towards the remediation of fire safety problems—a figure that still fell far short of the costs involved, many of which were being borne by owners of flats who had bought them in the belief that they had been built legally.


title: Grenfell Tower fire

text: On 22 June 2020, another London tower block, "Ferrier Point" in Canning Town, Newham was evacuated after a flat fire that occurred on the fourth floor of the tower at around 18:20. Around 60 firefighters attended to take down the fire, of which it was under control by 20:15. The tower block contained the exact same aluminium composite cladding as the one at Grenfell, which was removed just a year before the fire occurred. Residents were noted as saying that the just-in-time removal of the cladding prevented another tragedy on the scale of Grenfell.


title: Grenfell Tower fire

text: In Australia, authorities decided to remove similar cladding from all its tower blocks. It was stated that every tower block built in Melbourne in the previous 20 years had the cladding. In Malta, the Chamber of Engineers and the Chamber of Architects urged the Maltese Government to update the building regulations with regards to fire safety. On 27 June 2017, an 11-storey tower block in Wuppertal, North Rhine-Westphalia, Germany was evacuated after it was found that the cladding was similar to that installed on Grenfell Tower.


title: Grenfell Tower fire

text: A month after the fire at Grenfell Tower the external cladding of the newly built 433-room Hilton Hotel at Schiphol airport in The Netherlands was partly removed, over concerns of fire safety. Allegedly due to financial problems at the supplier, the material used did not meet the approved standards. Additional to the replacement, an external video system was installed specifically to detect fires.


title: Grenfell Tower fire

text: Also a university building in Rotterdam was found to have the same cladding and was subsequently closed and refurbished. 'Dozens' of other buildings in The Netherlands allegedly suffer the same defects.


title: Grenfell Tower fire

text: In response to Grenfell Tower and similar high-rise fires in the Middle East involving exterior cladding, the United Arab Emirates updated its Fire and Life Safety Code in 2018 to mandate the use of the NFPA 285 fire safety test.


title: Grenfell Tower fire

text: The local borough pledged to carry out a full investigation into the fire. Prime Minister Theresa May ordered a full public inquiry, saying that people "deserve answers" to why the fire was able to spread as quickly as it did.


title: Grenfell Tower fire

text: In July 2017, the government offered an amnesty to those who had been illegally sub-letting and a one-year immigration amnesty to those who came forward with information, though did not offer a full guarantee against deportation. On 31 August 2017 Immigration Minister Brandon Lewis announced that the deadline to register for the one-year immigration amnesty for displaced undocumented residents of Grenfell Tower was to be extended by three months to 30 November 2017. Sir Martin Moore-Bick (who leads the public inquiry) wrote to the Prime Minister asking her to consider the long term future for these residents beyond their value as witnesses for the inquiry. These views were echoed by campaign groups BMELawyers4Grenfell and Justice4Grenfell.


title: Grenfell Tower fire

text: On 16 September 2019 it was reported that London Fire Brigade as a body have been interviewed by Metropolitan Police under caution in respect of the Health and Safety at Work etc. Act 1974. In a press statement, LFB Commissioner Dany Cotton said the Brigade had been subject to police investigation from just after the fire; hundreds of officers had given voluntary police interviews; and LFB would continue to assist investigators.


title: Grenfell Tower fire

text: Leilani Farha argued that the failings of Grenfell Tower were a breach of residents' human rights, because they were not sufficiently involved in the way the building was developed, notably safety issues, before the fire and are not sufficiently involved in the investigations after the fire.


title: Grenfell Tower fire

text: On 15 June 2017, Metropolitan Police Commander Stuart Cundy announced that a criminal investigation had been opened to establish if there was any case for charges to be brought. On 27 July 2017 Police issued a public notice to residents saying that they had "reasonable grounds" to suspect that both the Royal Borough of Kensington and Chelsea and the Kensington and Chelsea Tenant Management Organisation "may have committed" corporate manslaughter. Senior representatives of both organisations are likely to face police interviews under caution. More than sixty companies and organisations are associated with Grenfell Tower, and as of July 2017, police were keeping open all options for a range of possible charges. These include manslaughter, corporate manslaughter, misconduct in public office and fire safety offences.


title: Grenfell Tower fire

text: In an interview with the London Evening Standard on 7 August 2017, the Director of Public Prosecutions, Alison Saunders, said investigations are at an early stage and nothing is ruled out. Mrs Saunders said it was more important to build strong cases than to rush to court, and that the DPP had yet to see the evidence. Health and safety legislation and other criminal laws will be considered. If proven, the offence of Gross Negligence Manslaughter carries a maximum life sentence, with a guideline minimum of twelve years. For such a charge the prosecution must show sufficient evidence to pass a four stage "Adomako Test" proving a reprehensible breach of duty of care which caused or contributed to the victims' death.


title: Grenfell Tower fire

text: On 7 June 2018, BBC News reported that the Met Police are investigating the London Fire Brigade for using the "Stay Put" policy. Possible criminal offences under the Health and Safety at Work Act are under consideration.


title: Grenfell Tower fire

text: , thirteen interviews had been held under caution with more expected, and 7,100 statements had been taken from witnesses, family members, emergency service personnel and others. In March 2019, it was revealed that no criminal charges are due to be brought before late 2021. The Metropolitan Police explained that all evidence had to be considered before a case could be put before the Crown Prosecution Service. Phase 2 of the public enquiry is unlikely to start before 2020, and no case can be brought until after the report has been published.


title: Grenfell Tower fire

text: On 19 September 2017, Commander Stuart Cundy briefed that eight people were being investigated for allegedly making false claims to financial support in the name of fictitious victims. By 1 June 2018, five people had been convicted for fraud offences after stating they were victims of the fire to claim financial support.


title: Grenfell Tower fire

text: New arrests were made in London on 7 June 2018 of a further nine people suspected of fraud. Four were charged a day later. Three people were charged with fraud while one additional suspect was initially charged with drug and theft offences but was eventually charged with fraud on 19 July. The other five were released under investigation.


title: Grenfell Tower fire

text: By March 2020, twenty one people had been charged with fraud offences relating to the fire, with all of them being found guilty after twenty investigations by the Metropolitan Police and one investigation by the City of London Police Insurance Fraud Enforcement Department. They were given prison sentences totaling almost 90 years in total after fraudulently claiming around £1 million in pre-paid credit cards, hotel accommodation costs and other funds intended for the victims of the fire.


title: Grenfell Tower fire

text: All of those convicted of fraud stated that they lived in the tower block and that their homes had been destroyed, and many said that members of their family had been killed. They spent their money on lavish holidays, expensive cars and gambling, and some even asked for more money after complaining about the food and WiFi in the hotels they were being housed in. Three of those convicted were also found to have been illegal immigrants living in the UK, and one man was caught with quantities of illegal drugs in his hotel room. Another man was also found to have committed a burglary. A woman who pretended to be a Grenfell victim was found to have made more than fifty false claims to insurers and to have also said she was present at the Manchester Arena bombing and the London Bridge attack just weeks earlier.


title: Grenfell Tower fire

text: Detailed investigations into the causes and possible criminal charges of manslaughter or breach of regulations are in progress. Search dogs, fingertip searches, DNA matching, fingerprinting, forensic dentistry and forensic anthropologists have been used. An external lift was fitted to the building to improve access.


title: Grenfell Tower fire

text: The scale of the search and recovery operation was challenging. Human remains were mixed within an estimated of debris on every floor. Time and care was taken to maintain a judicial standard and avoid mistaken identity, which could have caused further distress to surviving relatives. Disaster Victim Identification was expected by police to continue to 2018.


title: Grenfell Tower fire

text: Following the "Newsnight" report of 7 July 2017, the LFB said issues encountered in its response to the fire would also form part of the police investigation. LFB Commissioner Dany Cotton said in a "Channel 4 News" interview on 11 July 2017 that she expected reasonable criticism of the LFB response in the investigation and public inquiry. Following criticism by survivors and victims families, Cotton retired early at the end of December 2019. Her replacement from 1 January 2020 is Deputy Commissioner Andrew Roe.


title: Grenfell Tower fire

text: BBC Radio 4 reported on 16 August 2017 that the Fire Brigade was advised by KCTMO during the refurbishment and fire officers had been shown "fire safety features". Council opposition leader Robert Atkinson, structural engineer Paul Follows and building inspector Geoff Wilkinson all expressed shock that the fire had happened given prior consultation with LFB.


title: Grenfell Tower fire

text: London Fire Brigade said it had not given approval for the work, saying its legal powers are limited. It said firefighters regularly visit buildings to gain familiarity with the layout and equipment, but that this was not the same as a detailed inspection.


title: Grenfell Tower fire

text: One day after the fire broke out, Prime Minister Theresa May announced a public inquiry into the causes of the fire. Two weeks later, Sir Martin Moore-Bick was appointed to lead it. He pledged that the inquiry would be "open, transparent and fair". The inquiry will run alongside the criminal investigations.


title: Grenfell Tower fire

text: On 15 August 2017, Theresa May announced the terms of reference, accepting in full Moore-Bick's proposals. The inquiry plans to examine the cause and spread of the fire, the adequacy and enforcement of building regulations and fire protection measures, the actions of the council and KCTMO prior to the fire, and the responses of the London Fire Brigade, council and national government. Labour Party politicians and some survivors called for the inquiry to include a broader examination of national social housing policy, which was not included in the terms of reference. The inquiry's public hearings started on 14 September 2017.


title: Grenfell Tower fire

text: The first report (Phase 1) from the inquiry was officially published on 30 October 2019, but had been leaked and publicised during the press embargo. Originally due in spring 2019, the date was pushed back to October. Moore-Bick told survivors the timing disappointed him.


title: Grenfell Tower fire

text: Moore-Bick's report affirmed the exterior cladding was the primary reason the fire spread out of control, and that it did not comply with the building regulations. He praised the "courage and devotion to duty" of the firefighters but argued LFB suffered from "significant systemic failings" and that incident commanders were not trained to deal with a failure of compartmentalisation of this scale. The report was welcomed by survivors. On 6 December, Dany Cotton announced she would retire earlier than planned.


title: Grenfell Tower fire

text: The "Following Grenfell" report (March 2019) observes that children who witnessed the fire, or who have lost a friend or part of their family, don't know where or how to access help because the services are not available.


title: Grenfell Tower fire

text: The EHRC report expressed particular concern around the placing of disabled people, including wheelchair users, on upper storeys of tower blocks without any consideration about how they could escape in a fire or other emergency. The report considered disabled people had faced discriminatory treatment amounting to breaches of the right to life, the right to safe, adequate housing; and the right to freedom from cruel, inhuman and degrading treatment, further noting that degrading treatment continued after the fire with disabled people being housed in inaccessible premises.


title: Grenfell Tower fire

text: On 11 June 2019, survivors and families of the victims of the fire filed a civil action complaint in the Court of Common Pleas of the First Judicial District of Pennsylvania in Philadelphia against Arconic and Celotex (both of which are headquartered in Pennsylvania), seeking an unspecified amount of money damages for various product liability claims. The 420-page complaint alleges that the cladding and insulation were defective because they lacked fire retardant and were therefore combustible. Whirlpool, the Michigan-based manufacturer of the Hotpoint refrigerator believed to have caused the fire, was also named as a defendant in the suit on the grounds that the refrigerator contained materials liable to catch fire. Litigation is expected to take at least two and a half years due to the long process of discovery.


title: Grenfell Tower fire

text: By August, the defendants had exercised their right to remove the case to the appropriate federal court: the United States District Court for the Eastern District of Pennsylvania. In November 2019, Arconic resisted production of documents (which were already in the possession of its American lawyers at DLA Piper) on the basis that the cladding at issue had been manufactured by a French subsidiary, Arconic Architectural Products SAS, and that French law prohibits the production of commercial information in foreign legal proceedings without authorization by a French court. According to its US corporate filings, as of November 2019, Arconic had already spent approximately £30 million on lawyers and advisers to respond to all the criminal and civil investigations, inquiries, and litigation arising out of the fire.


title: Grenfell Tower fire

text: Grenfell Tower site manager Michael Lockwood told a public meeting on 26 July 2017 that the building would be covered in a protective wrap supported by scaffolding. This is to protect forensic evidence but would later allow the building to be taken down. The community will be consulted on how the space should be used after demolition.


title: Grenfell Tower fire

text: , deconstruction has still not started, more than five years later. Structural engineers have advised that the tower poses a risk. The government has said the tower should be "carefully taken down". Plans for the site are expected to be published by the Grenfell Tower Memorial Commission, established in 2018. Lockwood and Thelma Stober were elected as co-chairs in 2020.


title: Grenfell Tower fire

text: The following are similar fires that spread through exterior wall assemblies (cladding, insulation, wall) containing combustible components. Most of them involved high-rise buildings.


title: First law of thermodynamics

text: The first law of thermodynamics is a formulation of the law of conservation of energy, adapted for thermodynamic processes. It distinguishes in principle two forms of energy transfer, heat and thermodynamic work for a system of a constant amount of matter. The law also defines the internal energy of a system, an extensive property for taking account of the balance of energies in the system.


title: First law of thermodynamics

text: The law of conservation of energy states that the total energy of any isolated system, which cannot exchange energy or matter, is constant. Energy can be transformed from one form to another, but can be neither created nor destroyed.


title: First law of thermodynamics

text: where formula_2 denotes the change in the internal energy of a closed system (for which heat or work through the system boundary are possible, but matter transfer is not possible), formula_3 denotes the quantity of energy supplied "to" the system as heat, and formula_4 denotes the amount of thermodynamic work done "by" the system "on" its surroundings.


title: First law of thermodynamics

text: An equivalent statement is that perpetual motion machines of the first kind are impossible; work formula_4 done by a system on its surroundings requires that the system's internal energy formula_6 decrease or be consumed, so that the amount of internal energy lost by that work must be resupplied as heat formula_3 by an external energy source or as work by an external machine acting on the system (so that formula_6 is recovered) to make the system work continuously.


title: First law of thermodynamics

text: The ideal isolated system, of which the entire universe is an example, is often only used as a model. Many systems in practical applications require the consideration of internal chemical or nuclear reactions, as well as transfers of matter into or out of the system. For such considerations, thermodynamics also defines the concept of open systems, closed systems, and other types.


title: First law of thermodynamics

text: In the first half of the eighteenth century, French philosopher and mathematician Émilie du Châtelet made notable contributions to the emerging theoretical framework of energy by proposing a form of the law of conservation of energy that recognized the inclusion of kinetic energy. Empirical developments of the early ideas, in the century following, wrestled with contravening concepts such as the caloric theory of heat.


title: First law of thermodynamics

text: In 1840, Germain Hess stated a conservation law ("Hess's Law") for the "heat of reaction" during chemical transformations. This law was later recognized as a consequence of the first law of thermodynamics, but Hess's statement was not explicitly concerned with the relation between energy exchanges by heat and work.


title: First law of thermodynamics

text: In 1842, Julius Robert von Mayer made a statement that was expressed by Clifford Truesdell (1980) in the rendition "in a process at constant pressure, the heat used to produce expansion is universally interconvertible with work", but this is not a general statement of the first law.


title: First law of thermodynamics

text: The first full statements of the law came in 1850 from Rudolf Clausius, and from William Rankine. Some scholars consider Rankine's statement less distinct than that of Clausius.


title: First law of thermodynamics

text: The original 19th-century statements of the first law of thermodynamics appeared in a conceptual framework in which transfer of energy as heat was taken as a primitive notion, not defined or constructed by the theoretical development of the framework, but rather presupposed as prior to it and already accepted. The primitive notion of heat was taken as empirically established, especially through calorimetry regarded as a subject in its own right, prior to thermodynamics. Jointly primitive with this notion of heat were the notions of empirical temperature and thermal equilibrium. This framework also took as primitive the notion of transfer of energy as work. This framework did not presume a concept of energy in general, but regarded it as derived or synthesized from the prior notions of heat and work. By one author, this framework has been called the "thermodynamic" approach.


title: First law of thermodynamics

text: The first explicit statement of the first law of thermodynamics, by Rudolf Clausius in 1850, referred to cyclic thermodynamic processes.


title: First law of thermodynamics

text: Clausius also stated the law in another form, referring to the existence of a function of state of the system, the internal energy, and expressed it in terms of a differential equation for the increments of a thermodynamic process. This equation may be described as follows:


title: First law of thermodynamics

text: Because of its definition in terms of increments, the value of the internal energy of a system is not uniquely defined. It is defined only up to an arbitrary additive constant of integration, which can be adjusted to give arbitrary reference zero levels. This non-uniqueness is in keeping with the abstract mathematical nature of the internal energy. The internal energy is customarily stated relative to a conventionally chosen standard reference state of the system.


title: First law of thermodynamics

text: The concept of internal energy is considered by Bailyn to be of "enormous interest". Its quantity cannot be immediately measured, but can only be inferred, by differencing actual immediate measurements. Bailyn likens it to the energy states of an atom, that were revealed by Bohr's energy relation "hν" = "E" − "E". In each case, an unmeasurable quantity (the internal energy, the atomic energy level) is revealed by considering the difference of measured quantities (increments of internal energy, quantities of emitted or absorbed radiative energy).


title: First law of thermodynamics

text: In 1907, George H. Bryan wrote about systems between which there is no transfer of matter (closed systems): "Definition. When energy flows from one system or part of a system to another otherwise than by the performance of mechanical work, the energy so transferred is called "heat"." This definition may be regarded as expressing a conceptual revision, as follows. This was systematically expounded in 1909 by Constantin Carathéodory, whose attention had been drawn to it by Max Born. Largely through Born's influence, this revised conceptual approach to the definition of heat came to be preferred by many twentieth-century writers. It might be called the "mechanical approach".


title: First law of thermodynamics

text: Energy can also be transferred from one thermodynamic system to another in association with transfer of matter. Born points out that in general such energy transfer is not resolvable uniquely into work and heat moieties. In general, when there is transfer of energy associated with matter transfer, work and heat transfers can be distinguished only when they pass through walls physically separate from those for matter transfer.


title: First law of thermodynamics

text: The "mechanical" approach postulates the law of conservation of energy. It also postulates that energy can be transferred from one thermodynamic system to another adiabatically as work, and that energy can be held as the internal energy of a thermodynamic system. It also postulates that energy can be transferred from one thermodynamic system to another by a path that is non-adiabatic, and is unaccompanied by matter transfer. Initially, it "cleverly" (according to Bailyn) refrains from labelling as 'heat' such non-adiabatic, unaccompanied transfer of energy. It rests on the primitive notion of "walls", especially adiabatic walls and non-adiabatic walls, defined as follows. Temporarily, only for purpose of this definition, one can prohibit transfer of energy as work across a wall of interest. Then walls of interest fall into two classes, (a) those such that arbitrary systems separated by them remain independently in their own previously established respective states of internal thermodynamic equilibrium; they are defined as adiabatic; and (b) those without such independence; they are defined as non-adiabatic.


title: First law of thermodynamics

text: This approach derives the notions of transfer of energy as heat, and of temperature, as theoretical developments, not taking them as primitives. It regards calorimetry as a derived theory. It has an early origin in the nineteenth century, for example in the work of Helmholtz, but also in the work of many others.


title: First law of thermodynamics

text: The revised statement of the first law postulates that a change in the internal energy of a system due to any arbitrary process, that takes the system from a given initial thermodynamic state to a given final equilibrium thermodynamic state, can be determined through the physical existence, for those given states, of a reference process that occurs purely through stages of adiabatic work.


title: First law of thermodynamics

text: This statement is much less close to the empirical basis than are the original statements, but is often regarded as conceptually parsimonious in that it rests only on the concepts of adiabatic work and of non-adiabatic processes, not on the concepts of transfer of energy as heat and of empirical temperature that are presupposed by the original statements. Largely through the influence of Max Born, it is often regarded as theoretically preferable because of this conceptual parsimony. Born particularly observes that the revised approach avoids thinking in terms of what he calls the "imported engineering" concept of heat engines.


title: First law of thermodynamics

text: Basing his thinking on the mechanical approach, Born in 1921, and again in 1949, proposed to revise the definition of heat. In particular, he referred to the work of Constantin Carathéodory, who had in 1909 stated the first law without defining quantity of heat. Born's definition was specifically for transfers of energy without transfer of matter, and it has been widely followed in textbooks (examples:). Born observes that a transfer of matter between two systems is accompanied by a transfer of internal energy that cannot be resolved into heat and work components. There can be pathways to other systems, spatially separate from that of the matter transfer, that allow heat and work transfer independent of and simultaneous with the matter transfer. Energy is conserved in such transfers.


title: First law of thermodynamics

text: The first law of thermodynamics for a closed system was expressed in two ways by Clausius. One way referred to cyclic processes and the inputs and outputs of the system, but did not refer to increments in the internal state of the system. The other way referred to an incremental change in the internal state of the system, and did not expect the process to be cyclic.


title: First law of thermodynamics

text: A cyclic process is one that can be repeated indefinitely often, returning the system to its initial state. Of particular interest for single cycle of a cyclic process are the net work done, and the net heat taken in (or 'consumed', in Clausius' statement), by the system.


title: First law of thermodynamics

text: In a cyclic process in which the system does net work on its surroundings, it is observed to be physically necessary not only that heat be taken into the system, but also, importantly, that some heat leave the system. The difference is the heat converted by the cycle into work. In each repetition of a cyclic process, the net work done by the system, measured in mechanical units, is proportional to the heat consumed, measured in calorimetric units.


title: First law of thermodynamics

text: The constant of proportionality is universal and independent of the system and in 1845 and 1847 was measured by James Joule, who described it as the "mechanical equivalent of heat".


title: First law of thermodynamics

text: In a general process, the change in the internal energy of a closed system is equal to net energy added as heat to the system minus the thermodynamic work done by the system, both being measured in mechanical units. Taking formula_2 as a change in internal energy, one writes


title: First law of thermodynamics

text: where formula_3 denotes the net quantity of heat supplied to the system by its surroundings and formula_4 denotes the net work done by the system. This sign convention is implicit in Clausius' statement of the law given above. It originated with the study of heat engines that produce useful work by consumption of heat; the key performance indicator of any heat engine is its thermal efficiency, which is the quotient of the net work done and the heat supplied to the system (disregarding waste heat given off). Thermal efficiency must be positive, which is the case if net work done and heat supplied are both of the same sign; by convention both are given the positive sign.


title: First law of thermodynamics

text: Nowadays, however, writers often use the IUPAC convention by which the first law is formulated with thermodynamic work done on the system by its surroundings having a positive sign. With this now often used sign convention for work, the first law for a closed system may be written:


title: First law of thermodynamics

text: Continuing in the Clausius sign convention for work, when a system expands in a quasistatic process, the thermodynamic work done by the system on the surroundings is the product, formula_14, of pressure, formula_15, and volume change, formula_16, whereas the thermodynamic work done "on" the system by the surroundings is formula_17. Using either sign convention for work, the change in internal energy of the system is:


title: First law of thermodynamics

text: where formula_19 denotes the infinitesimal amount of heat supplied to the system from its surroundings and formula_20 denotes an inexact differential.


title: First law of thermodynamics

text: Work and heat are expressions of actual physical processes of supply or removal of energy, while the internal energy formula_6 is a mathematical abstraction that keeps account of the exchanges of energy that befall the system. Thus the term 'heat' for formula_3 means "that amount of energy added or removed as heat in the thermodynamic sense", rather than referring to a form of energy within the system. Likewise, the term 'work energy' for formula_4 means "that amount of energy gained or lost through thermodynamic work". Internal energy is a property of the system whereas work done and heat supplied are not. A significant result of this distinction is that a given internal energy change formula_2 can be achieved by different combinations of heat and work. (This may be signaled by saying that heat and work are path dependent, while change in internal energy depends only on the initial and final states of the process. It is necessary to bear in mind that thermodynamic work is measured by change in the system, not necessarily the same as work measured by forces and distances in the surroundings; this distinction is noted in the term 'isochoric work' (at constant volume).)


title: First law of thermodynamics

text: The law is of great importance and generality and is consequently thought of from several points of view. Most careful textbook statements of the law express it for closed systems. It is stated in several ways, sometimes even by the same author.


title: First law of thermodynamics

text: For the thermodynamics of closed systems, the distinction between transfers of energy as work and as heat is central and is within the scope of the present article. For the thermodynamics of open systems, such a distinction is beyond the scope of the present article, but some limited comments are made on it in the section below headed 'First law of thermodynamics for open systems'.


title: First law of thermodynamics

text: There are two main ways of stating a law of thermodynamics, physically or mathematically. They should be logically coherent and consistent with one another.


title: First law of thermodynamics

text: This physical statement is restricted neither to closed systems nor to systems with states that are strictly defined only for thermodynamic equilibrium; it has meaning also for open systems and for systems with states that are not in thermodynamic equilibrium.


title: First law of thermodynamics

text: This statement by Crawford, for , uses the sign convention of IUPAC, not that of Clausius. Though it does not explicitly say so, this statement refers to closed systems. Usually, internal energy is evaluated for bodies in states of thermodynamic equilibrium, which possess well-defined temperatures, but in principle, it is more generally the sum of the kinetic and potential energies of all particles in the system, usually relative to a reference state.


title: First law of thermodynamics

text: The history of statements of the law for closed systems has two main periods, before and after the work of Bryan (1907), of Carathéodory (1909), and the approval of Carathéodory's work given by Born (1921). The earlier traditional versions of the law for closed systems are nowadays often considered to be out of date.


title: First law of thermodynamics

text: Carathéodory's celebrated presentation of equilibrium thermodynamics refers to closed systems, which are allowed to contain several phases connected by internal walls of various kinds of impermeability and permeability (explicitly including walls that are permeable only to heat). Carathéodory's 1909 version of the first law of thermodynamics was stated in an axiom which refrained from defining or mentioning temperature or quantity of heat transferred. That axiom stated that the internal energy of a phase in equilibrium is a function of state, that the sum of the internal energies of the phases is the total internal energy of the system, and that the value of the total internal energy of the system is changed by the amount of work done adiabatically on it, considering work as a form of energy. That article considered this statement to be an expression of the law of conservation of energy for such systems. This version is nowadays widely accepted as authoritative, but is stated in slightly varied ways by different authors.


title: First law of thermodynamics

text: Such statements of the first law for closed systems assert the existence of internal energy as a function of state defined in terms of adiabatic work. Thus heat is not defined calorimetrically or as due to temperature difference. It is defined as a residual difference between change of internal energy and work done on the system, when that work does not account for the whole of the change of internal energy and the system is not adiabatically isolated.


title: First law of thermodynamics

text: The 1909 Carathéodory statement of the law in axiomatic form does not mention heat or temperature, but the equilibrium states to which it refers are explicitly defined by variable sets that necessarily include "non-deformation variables", such as pressures, which, within reasonable restrictions, can be rightly interpreted as empirical temperatures, and the walls connecting the phases of the system are explicitly defined as possibly impermeable to heat or permeable only to heat.


title: First law of thermodynamics

text: According to Münster (1970), "A somewhat unsatisfactory aspect of Carathéodory's theory is that a consequence of the Second Law must be considered at this point [in the statement of the first law], i.e. that it is not always possible to reach any state 2 from any other state 1 by means of an adiabatic process." Münster instances that no adiabatic process can reduce the internal energy of a system at constant volume. Carathéodory's paper asserts that its statement of the first law corresponds exactly to Joule's experimental arrangement, regarded as an instance of adiabatic work. It does not point out that Joule's experimental arrangement performed essentially irreversible work, through friction of paddles in a liquid, or passage of electric current through a resistance inside the system, driven by motion of a coil and inductive heating, or by an external current source, which can access the system only by the passage of electrons, and so is not strictly adiabatic, because electrons are a form of matter, which cannot penetrate adiabatic walls. The paper goes on to base its main argument on the possibility of quasi-static adiabatic work, which is essentially reversible. The paper asserts that it will avoid reference to Carnot cycles, and then proceeds to base its argument on cycles of forward and backward quasi-static adiabatic stages, with isothermal stages of zero magnitude.


title: First law of thermodynamics

text: Sometimes the existence of the internal energy is made explicit but work is not explicitly mentioned in the statement of the first postulate of thermodynamics. Heat supplied is then defined as the residual change in internal energy after work has been taken into account, in a non-adiabatic process.


title: First law of thermodynamics

text: A respected modern author states the first law of thermodynamics as "Heat is a form of energy", which explicitly mentions neither internal energy nor adiabatic work. Heat is defined as energy transferred by thermal contact with a reservoir, which has a temperature, and is generally so large that addition and removal of heat do not alter its temperature. A current student text on chemistry defines heat thus: ""heat" is the exchange of thermal energy between a system and its surroundings caused by a temperature difference." The author then explains how heat is defined or measured by calorimetry, in terms of heat capacity, specific heat capacity, molar heat capacity, and temperature.


title: First law of thermodynamics

text: A respected text disregards the Carathéodory's exclusion of mention of heat from the statement of the first law for closed systems, and admits heat calorimetrically defined along with work and internal energy. Another respected text defines heat exchange as determined by temperature difference, but also mentions that the Born (1921) version is "completely rigorous". These versions follow the traditional approach that is now considered out of date, exemplified by that of Planck (1897/1903).


title: First law of thermodynamics

text: The first law of thermodynamics for closed systems was originally induced from empirically observed evidence, including calorimetric evidence. It is nowadays, however, taken to provide the definition of heat via the law of conservation of energy and the definition of work in terms of changes in the external parameters of a system. The original discovery of the law was gradual over a period of perhaps half a century or more, and some early studies were in terms of cyclic processes.


title: First law of thermodynamics

text: The following is an account in terms of changes of state of a closed system through compound processes that are not necessarily cyclic. This account first considers processes for which the first law is easily verified because of their simplicity, namely adiabatic processes (in which there is no transfer as heat) and adynamic processes (in which there is no transfer as work).


title: First law of thermodynamics

text: In an adiabatic process, there is transfer of energy as work but not as heat. For all adiabatic process that takes a system from a given initial state to a given final state, irrespective of how the work is done, the respective eventual total quantities of energy transferred as work are one and the same, determined just by the given initial and final states. The work done on the system is defined and measured by changes in mechanical or quasi-mechanical variables external to the system. Physically, adiabatic transfer of energy as work requires the existence of adiabatic enclosures.