text:
Interstitial cystitis

Interstitial cystitis (IC), a type of bladder pain syndrome (BPS), is chronic pain in the bladder and pelvic floor of unknown cause. It is the urologic chronic pelvic pain syndrome of women. Symptoms include feeling the need to urinate right away, needing to urinate often, and pain with sex. IC/BPS is associated with depression and lower quality of life. Many of those affected also have irritable bowel syndrome and fibromyalgia.

The cause of interstitial cystitis is unknown. While it can, it does not typically run in a family. The diagnosis is usually based on the symptoms after ruling out other conditions. Typically the urine culture is negative. Ulceration or inflammation may be seen on cystoscopy. Other conditions which can produce similar symptoms include overactive bladder, urinary tract infection (UTI), sexually transmitted infections, prostatitis, endometriosis in females, and bladder cancer.

There is no cure for interstitial cystitis and management of this condition can be challenging. Treatments that may improve symptoms include lifestyle changes, medications, or procedures. Lifestyle changes may include stopping smoking and reducing stress. Medications may include ibuprofen, pentosan polysulfate, or amitriptyline. Procedures may include bladder distention, nerve stimulation, or surgery. Kegel exercises and long term antibiotics are not recommended.

In the United States and Europe, it is estimated that around 0.5% of people are affected. Women are affected about five times as often as men. Onset is typically in middle age. The term "interstitial cystitis" first came into use in 1887.

Signs and symptoms
The most common symptoms of IC/BPS are suprapubic pain, urinary frequency, painful sexual intercourse, and waking up from sleep to urinate.

In general, symptoms may include painful urination described as a burning sensation in the urethra during urination, pelvic pain that is worsened with the consumption of certain foods or drinks, urinary urgency, and pressure in the bladder or pelvis. Other frequently described symptoms are urinary hesitancy (needing to wait for the urinary stream to begin, often caused by pelvic floor dysfunction and tension), and discomfort and difficulty driving, working, exercising, or traveling. Pelvic pain experienced by those with IC typically worsens with filling of the urinary bladder and may improve with urination.

During cystoscopy, 5–10% of people with IC are found to have Hunner's ulcers. A person with IC may have discomfort only in the urethra, while another might struggle with pain in the entire pelvis. Interstitial cystitis symptoms usually fall into one of two patterns: significant suprapubic pain with little frequency or a lesser amount of suprapubic pain but with increased urinary frequency.

Association with other conditions
Some people with IC/BPS have been diagnosed with other conditions such as irritable bowel syndrome (IBS), fibromyalgia, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), allergies, Sjögren syndrome, which raises the possibility that interstitial cystitis may be caused by mechanisms that cause these other conditions. There is also some evidence of an association between urologic pain syndromes, such as IC/BPS and CP/CPPS, with non-celiac gluten sensitivity in some people.

In addition, men with IC/PBS are frequently diagnosed as having chronic nonbacterial prostatitis, and there is an extensive overlap of symptoms and treatment between the two conditions, leading researchers to posit that the conditions may share the same cause and pathology.

Causes
The cause of IC/BPS is not known. However, several explanations have been proposed and include the following: autoimmune theory, nerve theory, mast cell theory, leaky lining theory, infection theory, and a theory of production of a toxic substance in the urine. Other suggested etiological causes are neurologic, allergic, genetic, and stress-psychological. In addition, recent research shows that those with IC may have a substance in the urine that inhibits the growth of cells in the bladder epithelium. An infection may then predispose those people to develop IC. Evidence from clinical and laboratory studies confirms that mast cells play a central role in IC/BPS possibly due to their ability to release histamine and cause pain, swelling, scarring, and interfere with healing. Research has shown a proliferation of nerve fibers is present in the bladders of people with IC which is absent in the bladders of people who have not been diagnosed with IC.

Regardless of the origin, most people with IC/BPS struggle with a damaged urothelium, or bladder lining. When the surface glycosaminoglycan (GAG) layer is damaged (via a urinary tract infection (UTI), traumatic injury, etc.), urinary chemicals can "leak" into surrounding tissues, causing pain, inflammation, and urinary symptoms. Oral medications like pentosan polysulfate and medications placed directly into the bladder via a catheter sometimes work to repair and rebuild this damaged/wounded lining, allowing for a reduction in symptoms. Most literature supports the belief that IC's symptoms are associated with a defect in the bladder epithelium lining, allowing irritating substances in the urine to penetrate into the bladder—a breakdown of the bladder lining (also known as the adherence theory). Deficiency in this glycosaminoglycan layer on the surface of the bladder results in increased permeability of the underlying submucosal tissues.

GP51 has been identified as a possible urinary biomarker for IC with significant variations in GP51 levels in those with IC when compared to individuals without interstitial cystitis.

Numerous studies have noted the link between IC, anxiety, stress, hyper-responsiveness, and panic. Another proposed mechanism for interstitial cystitis is the autoimmune mechanism. Biopsies on the bladder walls of people with IC may contain mast cells. Mast cells, which contain histamine granules, respond to allergic stimuli. In this theory, Mast cells are activated in response to antigen detection in the bladder wall. The activation of mast cells triggers the release of histamine, amongst other inflammatory mediators. Additionally, another proposed mechanism is increased activity of unspecified nerves in the bladder wall. An unknown toxin or stimuli may activate nerves within the bladder wall, causing the release of neuropeptides. These neuropeptides can induce a secondary cascade which stimulates pain in the bladder wall.

Genes
Some genetic subtypes, in some people, have been linked to the disorder.
 * An antiproliferative factor is secreted by the bladders of people with IC/BPS which inhibits bladder cell proliferation, thus possibly causing the missing bladder lining.
 * PAND, at gene map locus 13q22–q32, is associated with a constellation of disorders (a "pleiotropic syndrome") including IC/BPS and other bladder and kidney problems, thyroid diseases, serious headaches/migraines, panic disorder, and mitral valve prolapse.

Diagnosis
A diagnosis of IC/BPS is one of exclusion, as well as a review of clinical symptoms. The American Urological Association Guidelines recommend starting with a careful history of the person, physical examination and laboratory tests to assess and document symptoms of interstitial cytitis, as well as other potential disorders.

The KCl test, also known as the potassium sensitivity test, is no longer recommended. The test uses a mild potassium solution to evaluate the integrity of the bladder wall. Though the latter is not specific for IC/BPS, it has been determined to be helpful in predicting the use of compounds, such as pentosan polysulphate, which are designed to help repair the GAG layer.

For complicated cases, the use of hydrodistention with cystoscopy may be helpful. Researchers, however, determined that this visual examination of the bladder wall after stretching the bladder was not specific for IC/BPS and that the test, itself, can contribute to the development of small glomerulations (petechial hemorrhages) often found in IC/BPS. Thus, a diagnosis of IC/BPS is one of exclusion, as well as a review of clinical symptoms.

In 2006, the ESSIC society proposed more rigorous and demanding diagnostic methods with specific classification criteria so that it cannot be confused with other, similar conditions. Specifically, they require that a person must have pain associated with the bladder, accompanied by one other urinary symptom. Thus, a person with just frequency or urgency would be excluded from a diagnosis. Secondly, they strongly encourage the exclusion of confusable diseases through an extensive and expensive series of tests including (A) a medical history and physical exam, (B) a dipstick urinalysis, various urine cultures, and a serum PSA in men over 40, (C) flowmetry and post-void residual urine volume by ultrasound scanning and (D) cystoscopy. A diagnosis of IC/BPS would be confirmed with a hydrodistention during cystoscopy with biopsy.

They also propose a ranking system based upon the physical findings in the bladder. People would receive a numeric and letter based score based upon the severity of their disease as found during the hydrodistention. A score of 1–3 would relate to the severity of the disease and a rating of A–C represents biopsy findings. Thus, a person with 1A would have very mild symptoms and disease while a person with 3C would have the worst possible symptoms. Widely recognized scoring systems such as the O'Leary Sant symptom and problem score have emerged to evaluate the severity of IC symptoms such as pain and urinary symptoms.

Differential diagnosis
The symptoms of IC/BPS are often misdiagnosed as a urinary tract infection. However, IC/BPS has not been shown to be caused by a bacterial infection and antibiotics are an ineffective treatment. IC/BPS is commonly misdiagnosed as chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) in men, and endometriosis and uterine fibroids (in women).

Treatment
In 2011, the American Urological Association released consensus-based guideline for the diagnosis and treatment of interstitial cystitis.

They include treatments ranging from conservative to more invasive:
 * 1) First-line treatments – education, self care (diet modification), stress management
 * 2) Second-line treatments – physical therapy, oral medications (amitriptyline, cimetidine or hydroxyzine, pentosan polysulfate), bladder instillations (DMSO, heparin, or lidocaine)
 * 3) Third-line treatments – treatment of Hunner's lesions (laser, fulguration or triamcinolone injection), hydrodistention (low pressure, short duration)
 * 4) Fourth-line treatments – neuromodulation (sacral or pudendal nerve)
 * 5) Fifth-line treatments – cyclosporine A, botulinum toxin (BTX-A)
 * 6) Sixth-line treatments – surgical intervention (urinary diversion, augmentation, cystectomy)

The American Urological Association guidelines also listed several discontinued treatments, including long-term oral antibiotics, intravesical bacillus Calmette Guerin, intravesical resiniferatoxin), high-pressure and long-duration hydrodistention, and systemic glucocorticoids.

Bladder distension
Bladder distension while under general anesthesia, also known as hydrodistention (a procedure which stretches the bladder capacity), has shown some success in reducing urinary frequency and giving short-term pain relief to those with IC. However, it is unknown exactly how this procedure causes pain relief. Recent studies show pressure on pelvic trigger points can relieve symptoms. The relief achieved by bladder distensions is only temporary (weeks or months), so is not viable as a long-term treatment for IC/BPS. The proportion of people with IC/BPS who experience relief from hydrodistention is currently unknown and evidence for this modality is limited by a lack of properly controlled studies. Bladder rupture and sepsis may be associated with prolonged, high-pressure hydrodistention.

Bladder instillations
Bladder instillation of medication is one of the main forms of treatment of interstitial cystitis, but evidence for its effectiveness is currently limited. Advantages of this treatment approach include direct contact of the medication with the bladder and low systemic side effects due to poor absorption of the medication. Single medications or a mixture of medications are commonly used in bladder instillation preparations. Dimethyl sulfoxide (DMSO) is the only approved bladder instillation for IC/BPS yet it is much less frequently used in urology clinics.

A 50% solution of DMSO had the potential to create irreversible muscle contraction. However, a lesser solution of 25% was found to be reversible. Long-term use of DMSO is questionable, as its mechanism of action is not fully understood though DMSO is thought to inhibit mast cells and may have anti-inflammatory, muscle-relaxing, and analgesic effects. Other agents used for bladder instillations to treat interstitial cystitis include: heparin, lidocaine, chondroitin sulfate, hyaluronic acid, pentosan polysulfate, oxybutynin, and botulinum toxin A. Preliminary evidence suggests these agents are efficacious in reducing symptoms of interstitial cystitis, but further study with larger, randomized, controlled clinical trials is needed.

Diet
Diet modification is often recommended as a first-line method of self-treatment for interstitial cystitis, though rigorous controlled studies examining the impact diet has on interstitial cystitis signs and symptoms are currently lacking. An increase in fiber intake may alleviate symptoms. Individuals with interstitial cystitis often experience an increase in symptoms when they consume certain foods and beverages. Avoidance of these potential trigger foods and beverages such as caffeine-containing beverages including coffee, tea, and soda, alcoholic beverages, chocolate, citrus fruits, hot peppers, and artificial sweeteners may be helpful in alleviating symptoms. Diet triggers vary between individuals with IC; the best way for a person to discover his or her own triggers is to use an elimination diet. Sensitivity to trigger foods may be reduced if calcium glycerophosphate and/or sodium bicarbonate is consumed. The foundation of therapy is a modification of diet to help people avoid those foods which can further irritate the damaged bladder wall.

The mechanism by which dietary modification benefits people with IC is unclear. Integration of neural signals from pelvic organs may mediate the effects of diet on symptoms of IC.

Medications
The antihistamine hydroxyzine failed to demonstrate superiority over placebo in treatment of people with IC in a randomized, controlled, clinical trial. Amitriptyline has been shown to be effective in reducing symptoms such as chronic pelvic pain and nocturia in many people with IC/BPS with a median dose of 75 mg daily. In one study, the antidepressant duloxetine was found to be ineffective as a treatment, although a patent exists for use of duloxetine in the context of IC, and is known to relieve neuropathic pain. The calcineurin inhibitor cyclosporine A has been studied as a treatment for interstitial cystitis due to its immunosuppressive properties. A prospective randomized study found cyclosporine A to be more effective at treating IC symptoms than pentosan polysulfate, but also had more adverse effects.

Oral pentosan polysulfate is believed to repair the protective glycosaminoglycan coating of the bladder, but studies have encountered mixed results when attempting to determine if the effect is statistically significant compared to placebo.

Pelvic floor treatments
Urologic pelvic pain syndromes, such as IC/BPS and CP/CPPS, are characterized by pelvic muscle tenderness, and symptoms may be reduced with pelvic myofascial physical therapy.

This may leave the pelvic area in a sensitized condition, resulting in a loop of muscle tension and heightened neurological feedback (neural wind-up), a form of myofascial pain syndrome. Current protocols, such as the Wise–Anderson Protocol, largely focus on stretches to release overtensed muscles in the pelvic or anal area (commonly referred to as trigger points), physical therapy to the area, and progressive relaxation therapy to reduce causative stress.

Pelvic floor dysfunction is a fairly new area of specialty for physical therapists worldwide. The goal of therapy is to relax and lengthen the pelvic floor muscles, rather than to tighten and/or strengthen them as is the goal of therapy for people with urinary incontinence. Thus, traditional exercises such as Kegel exercises, which are used to strengthen pelvic muscles, can provoke pain and additional muscle tension. A specially trained physical therapist can provide direct, hands on evaluation of the muscles, both externally and internally.

A therapeutic wand can also be used to perform pelvic floor muscle myofascial release to provide relief.

Surgery
Surgery is rarely used for IC/BPS. Surgical intervention is very unpredictable, and is considered a treatment of last resort for severe refractory cases of interstitial cystitis. Some people who opt for surgical intervention continue to experience pain after surgery. Typical surgical interventions for refractory cases of IC/BPS include: bladder augmentation, urinary diversion, transurethral fulguration and resection of ulcers, and bladder removal (cystectomy).

Neuromodulation can be successful in treating IC/BPS symptoms, including pain. One electronic pain-killing option is TENS. Percutaneous tibial nerve stimulation stimulators have also been used, with varying degrees of success. Percutaneous sacral nerve root stimulation was able to produce statistically significant improvements in several parameters, including pain.

Alternative medicine
There is little evidence looking at the effects of alternative medicine though their use is common. There is tentative evidence that acupuncture may help pain associated with IC/BPS as part of other treatments. Despite a scarcity of controlled studies on alternative medicine and IC/BPS, "rather good results have been obtained" when acupuncture is combined with other treatments.

Biofeedback, a relaxation technique aimed at helping people control functions of the autonomic nervous system, has shown some benefit in controlling pain associated with IC/BPS as part of a multimodal approach that may also include medication or hydrodistention of the bladder.

Prognosis
IC/BPS has a profound impact on quality of life. A 2007 Finnish epidemiologic study showed that two-thirds of women at moderate to high risk of having interstitial cystitis reported impairment in their quality of life and 35% of people with IC reported an impact on their sexual life. A 2012 survey showed that among a group of adult women with symptoms of interstitial cystitis, 11% reported suicidal thoughts in the past two weeks. Other research has shown that the impact of IC/BPS on quality of life is severe and may be comparable to the quality of life experienced in end-stage kidney disease or rheumatoid arthritis.

International recognition of interstitial cystitis has grown and international urology conferences to address the heterogeneity in diagnostic criteria have recently been held. IC/PBS is now recognized with an official disability code in the United States of America.

Epidemiology
IC/BPS affects men and women of all cultures, socioeconomic backgrounds, and ages. Although the disease was previously believed to be a condition of menopausal women, growing numbers of men and women are being diagnosed in their twenties and younger. IC/BPS is not a rare condition. Early research suggested that the number of IC/BPS cases ranged from 1 in 100,000 to 5.1 in 1,000 of the general population. In recent years, the scientific community has achieved a much deeper understanding of the epidemiology of interstitial cystitis. Recent studies have revealed that between 2.7 and 6.53 million women in the USA have symptoms of IC and up to 12% of women may have early symptoms of IC/BPS. Further study has estimated that the condition is far more prevalent in men than previously thought ranging from 1.8 to 4.2 million men having symptoms of interstitial cystitis.

The condition is officially recognized as a disability in the United States.

History
Philadelphia surgeon Joseph Parrish published the earliest record of interstitial cystitis in 1836 describing three cases of severe lower urinary tract symptoms without the presence of a bladder stone. The term "interstitial cystitis" was coined by Dr. Alexander Skene in 1887 to describe the disease. In 2002, the United States amended the Social Security Act to include interstitial cystitis as a disability. The first guideline for diagnosis and treatment of interstitial cystitis is released by a Japanese research team in 2009. The American Urological Association released the first American clinical practice guideline for diagnosing and treating IC/BPS in 2011 and has since (in 2014 and 2022) updated the guideline to maintain standard of care as knowledge of IC/BPS evolves.

Names
Originally called interstitial cystitis, this disorder was renamed to interstitial cystitis/bladder pain syndrome (IC/BPS) in the 2002–2010 timeframe. In 2007, the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) began using the umbrella term urologic chronic pelvic pain syndrome (UCPPS) to refer to pelvic pain syndromes associated with the bladder (e.g., interstitial cystitis/bladder pain syndrome) and with the prostate gland or pelvis (e.g., chronic prostatitis/chronic pelvic pain syndrome).

In 2008, terms currently in use in addition to IC/BPS include painful bladder syndrome, bladder pain syndrome and hypersensitive bladder syndrome, alone and in a variety of combinations. These different terms are being used in different parts of the world. The term "interstitial cystitis" is the primary term used in ICD-10 and MeSH. Grover et al. said, "The International Continence Society named the disease interstitial cystitis/painful bladder syndrome (IC/PBS) in 2002 [Abrams et al. 2002], while the Multinational Interstitial Cystitis Association have labeled it as painful bladder syndrome/interstitial cystitis (PBS/IC) [Hanno et al. 2005]. Recently, the European Society for the study of Interstitial Cystitis (ESSIC) proposed the moniker, 'bladder pain syndrome' (BPS) [van de Merwe et al. 2008]."

title: Interstitial cystitis


text:
ICI

ICI or Ici may refer to:

Companies and organisations

 * ICI Homes, builder, Florida. US
 * Former UK Imperial Chemical Industries
 * ICI Australia, later Orica
 * Independent Curators International, New York City, US
 * Indian Concrete Institute
 * Indian Citation Index
 * Institut des cultures d'Islam, Goutte d'Or district, Paris, France
 * Institute of Chemistry of Ireland, Irish Chemical Society
 * Institute of Cultural Inquiry, US art sponsor
 * International Colonial Institute, Brussels, Belgium
 * International Compact with Iraq, 2007 Iraq-UN
 * Investment Company Institute, US
 * Islamic Center of Irving, a mosque and Islamic community Center in Irving, Texas, US
 * A Woman's Place (bookstore), or Information Center Incorporate

Media

 * Ici (magazine) (in French), Montreal, Canada
 * Ici Radio-Canada, Canadian Broadcasting Corporation service from 2013
 * ICI (TV channel) (International Channel/Canal International), Montreal, Canada

Science and technology

 * Interactive Compilation Interface
 * Intracervical insemination

Other uses

 * NATO Istanbul Cooperation Initiative
 * Intercultural intelligence, the capability to function effectively in culturally diverse settings

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: ICI


text:
Imperial Chemical Industries

Imperial Chemical Industries (ICI) was a British chemical company. It was, for much of its history, the largest manufacturer in Britain. It was formed by the merger of four leading British chemical companies in 1926. Its headquarters were at Millbank in London. ICI was a constituent of the FT 30 and later the FTSE 100 indices.

ICI made general chemicals, plastics, paints, pharmaceuticals and speciality products, including food ingredients, speciality polymers, electronic materials, fragrances and flavourings. In 1991, ICI sold the agricultural and merchandising operations of BritAg and Scottish Agricultural Industries to Norsk Hydro. It de-merged its pharmaceutical bio-science businesses as Zeneca in 1993. In 2008, ICI was acquired by AkzoNobel, which immediately sold parts of ICI to Henkel and integrated ICI's remaining operations within its existing organisation.

Development of the business (1926–1944)

The company was founded in December 1926 from the merger of four companies: Brunner Mond, Nobel Explosives, the United Alkali Company, and British Dyestuffs Corporation. It established its head office at Millbank in London in 1928. Competing with DuPont and IG Farben, the new company produced chemicals, explosives, fertilisers, insecticides, dyestuffs, non-ferrous metals, and paints. In its first year turnover was £27 million.

In the 1920s and 1930s, the company played a key role in the development of new chemical products, including the dyestuff phthalocyanine (1929), the acrylic plastic Perspex (1932), Dulux paints (1932, co-developed with DuPont), polyethylene (1937), and polyethylene terephthalate fibre known as Terylene (1941). In 1940, ICI started British Nylon Spinners as a joint venture with Courtaulds.

ICI also owned the Sunbeam motorcycle business, which had come with Nobel Industries, and continued to build motorcycles until 1937.

During the Second World War, ICI was involved with the United Kingdom's nuclear weapons programme codenamed Tube Alloys.

Postwar innovation (1945–1990)
In the 1940s and 1950s, the company established its pharmaceutical business and developed a number of key products, including Paludrine (1940s, an anti-malarial drug), halothane (1951, an inhalational anaesthetic agent), propofol (1977, an intravenous anaesthetic agent), Inderal (1965, a beta-blocker), tamoxifen (1978, a frequently used drug for breast cancer), and PEEK (1979, a high performance thermoplastic). ICI formed ICI Pharmaceuticals in 1957.

ICI developed a fabric in the 1950s known as Crimplene, a thick polyester yarn used to make a fabric of the same name. The resulting cloth is heavy and wrinkle-resistant, and retains its shape well. The California-based fashion designer Edith Flagg was the first to import this fabric from Britain to the United States. During the first two years, ICI gave Flagg a large advertising budget to popularise the fabric across America.

In 1960, Paul Chambers became the first chairman appointed from outside the company. Chambers employed the consultancy firm McKinsey to help with reorganising the company. His eight-year tenure saw export sales double, but his reputation was severely damaged by a failed takeover bid for Courtaulds in 1961–62.

ICI was confronted with the nationalisation of its operations in Burma on 1 August 1962 as a consequence of the military coup.

In 1964, ICI acquired British Nylon Spinners (BNS), the company it had jointly set up in 1940 with Courtaulds. ICI surrendered its 37.5 per cent holding in Courtaulds and paid Courtaulds £2 million a year for five years, "to take account of the future development expenditure of Courtaulds in the nylon field." In return, Courtaulds transferred to ICI their 50 per cent holding in BNS. BNS was absorbed into ICI's existing polyester operation, ICI Fibres. The acquisition included BNS production plants in Pontypool, Gloucester and Doncaster, together with research and development in Pontypool.

Early pesticide development under ICI Plant Protection Division, with its plant at Yalding, Kent, research station at Jealott's Hill and HQ at Fernhurst Research Station included paraquat (1962, a herbicide), the insecticides pirimiphos-methyl in 1967 and pirimicarb in 1970, brodifacoum (a rodenticide) was developed in 1974; in the late 1970s, ICI was involved in the early development of synthetic pyrethroid insecticides such as lambda-cyhalothrin.

Peter Allen was appointed chairman between 1968 and 1971. He presided over the purchase of Viyella. Profits shrank under his tenure. During his tenure, ICI created the wholly owned subsidiary Cleveland Potash Ltd, for the construction of Boulby Mine in Redcar and Cleveland, North Yorkshire. The first shaft was dug in 1968, with full production from 1976. ICI jointly owned the mine with Anglo American, and then with De Beers, before complete ownership was transferred to Israel Chemicals Ltd in 2002.

Jack Callard was appointed chairman from 1971 to 1975. He almost doubled company profits between 1972 and 1974, and made ICI Britain's largest exporter. In 1971, the company acquired Atlas Chemical Industries Inc., a major American competitor.

In 1977, Imperial Metal Industries was divested as an independent quoted company. From 1982 to 1987, the company was led by the charismatic John Harvey-Jones. Under his leadership, the company acquired the Beatrice Chemical Division in 1985 and Glidden Coatings & Resins, a leading paints business, in 1986.

Reorganisation of the business (1991–2007)
By the early 1990s, plans were carried out to demerge the company, as a result of increasing competition and internal complexity that caused heavy retrenchment and slowing innovation. In 1991, ICI sold the agricultural and merchandising operations of BritAg and Scottish Agricultural Industries to Norsk Hydro, and fought off a hostile takeover bid from Hanson, who had acquired 2.8 per cent of the company. It also divested its soda ash products arm to Brunner Mond, ending an association with the trade that had existed since the company's inception, one that had been inherited from the original Brunner, Mond & Co. Ltd.

In 1992, the company sold its nylon business to DuPont. In 1993, the company de-merged its pharmaceutical bio-science businesses: pharmaceuticals, agrochemicals, specialities, seeds and biological products were all transferred into a new and independent company called Zeneca. Zeneca subsequently merged with Astra AB to form AstraZeneca.

Charles Miller Smith was appointed CEO in 1994, one of the few times that someone from outside ICI had been appointed to lead the company, Smith having previously been a director at Unilever. Shortly afterwards, the company acquired a number of former Unilever businesses in an attempt to move away from its historical reliance on commodity chemicals. In 1995, ICI acquired the American paint companies Devoe Paints, Fuller-O'Brien Paints and Grow Group. In 1997, ICI acquired National Starch & Chemical, Quest International, Unichema, and Crosfield, the speciality chemicals businesses of Unilever for $8 billion. This step was part of a strategy to move away from cyclical bulk chemicals and to progress up the value chain to become a higher growth, higher margin business. Later that year it went on to buy Rutz & Huber, a Swiss paints business.

Having taken on some £4 billion of debt to finance these acquisitions, the company had to sell off its commodity chemicals businesses:
 * Disposals of bulk chemicals businesses at that time included the sale of its Australian subsidiary, ICI Australia, for £1 billion in 1997, and of its polyester chemicals business to DuPont for $3 billion also in 1997.
 * In 1998, it bought Acheson Industries Inc., an electronic chemicals business.
 * In 2000, ICI sold its diisocyanate, advanced materials, and speciality chemicals businesses on Teesside and worldwide (including plants at Rozenburg in the Netherlands, and South Africa, Malaysia and Taiwan), and Tioxide, its titanium dioxide subsidiary, to Huntsman Corporation for £1.7 billion. It also sold the last of its industrial chemicals businesses to Ineos for £325 million.
 * In 2002, the ICI wholly transferred ownership of Boulby Mine to Israel Chemicals Ltd.
 * In 2006, the Company sold Quest International, its flavours and fragrances business, to Givaudan, for £1.2 billion and Uniqema, its oleochemical business, to Croda International, for £410 million.

Having sold much of its historically profitable commodities businesses, and many of the new speciality businesses which it had failed to integrate, the company consisted mainly of the Dulux paints business, which quickly found itself the subject of a takeover by AkzoNobel.

Takeover by AkzoNobel

Dutch firm AkzoNobel (owner of Crown Berger paints) bid £7.2 billion (€10.66 billion or $14.5 billion) for ICI in June 2007. An area of concern about a potential deal was ICI's British pension fund, which had a deficit of almost £700 million and future liabilities of more than £9 billion at the time. Regulatory issues in the UK and other markets where Dulux and Crown Paints brands each have significant market share were also a cause for concern for the boards of ICI and AkzoNobel. In the UK, any combined operation without divestments would have seen AkzoNobel have a 54 per cent market share in the paint market. The initial bid was rejected by the ICI board and the majority of shareholders. However, a subsequent bid for £8 billion (€11.82 billion) was accepted by ICI in August 2007, pending approval by regulators.

On 2 January 2008, completion of the takeover of ICI plc by AkzoNobel was announced. Shareholders of ICI received either £6.70 in cash or AkzoNobel loan notes to the value of £6.70 per one nominal ICI share. The adhesives business of ICI was transferred to Henkel as a result of the deal, while AkzoNobel agreed to sell its Crown Paints subsidiary to satisfy the concerns of the European Commissioner for Competition. The areas of concern regarding the ICI UK pension scheme were addressed by ICI and AkzoNobel.

Operations
ICI operated a number of chemical sites around the world. In the UK, the main plants were as follows:
 * Billingham Manufacturing Plant (in Stockton-on-Tees) and Wilton (in present-day Redcar and Cleveland): ICI used the Billingham site to manufacture fertilisers in the 1920s and went on to produce plastics at Billingham in 1934. During World War II it manufactured Synthonia, a synthetic ammonia for explosives. The Wilton R&D site was built to support the plastics division with R&D and chemical engineering facilities. The ICI Billingham Division was split into the ICI Heavy Organic Chemicals Division and ICI Agricultural Division in the 1960s. From 1971 to 1988 ICI Physics and Radioisotopes Section (later known as Tracerco) operated a small General Atomics TRIGA Mark I nuclear reactor at its Billingham factory for the production of radioisotopes used in the manufacture of flow and level instruments, among other products. The Agricultural Division was noted for the development of the world's largest bioreactor at the time – the 1.5 million litre Pruteen Reactor, used for the cultivation of animal feed. Engineering models of components and the builder's model of the complete plant are now in the collection of the Science Museum London . Pruteen had limited economic success but was followed by the much more successful development of Quorn.
 * Blackley (in Manchester) and Huddersfield: ICI used the sites to manufacture dyestuffs. The dye business, known as the ICI Dyestuffs Division in the 1960s, went through several reorganisations. Huddersfield was tied in with Wilton with the production of nitrobenzene and nitrotoluene. Huddersfield also produced insecticides. (Syngenta still manufacture insecticides at Huddersfield). Proxel Biocide was made at Huddersfield from the 80s onwards. Additives also made at Huddersield. Huddersfield became Zeneca then AstraZeneca, in 2004 Huddersfield was Syngenta, Avecia, Arch and Lubrizol running what were all ICI plants at one time.    Through the years it was combined with other speciality chemicals businesses and became Organics Division. Then became ICI Colours and Fine Chemicals and then ICI Specialties.
 * Runcorn (in Cheshire): ICI operated a number of separate sites within the Runcorn area, including the Castner-Kellner site, where ICI manufactured chlorine and sodium hydroxide (caustic soda). Adjacent to the Castner-Kellner site was Rocksavage works, where a variety of chemicals based on chlorine products were manufactured, including Chloromethanes, Arklone dry cleaning fluid, Trichloethylene degreasing fluid and the Arcton range of CFCs. Also on that site were PVC manufacture and HF (Hydrogen fluoride) manufacture. At Runcorn Heath Research Laboratories, technical support, research and development for Mond Division products was carried out, and the support sections included chemical plan design and engineering sections. Just to the north of Runcorn, on an island between the Manchester Ship Canal and the River Mersey could be found the Wigg Works, which had been erected originally for producing poison gas in wartime. In Widnes could also be found several factories producing weedkillers and other products. For many years it was known as ICI Mond Division but later became part of the ICI Chemicals and Polymers Division. The Runcorn site was also responsible for the development of the HiGEE and Spinning Disc Reactor concepts. These were originated by Professor Colin Ramshaw and led to the concept of Process Intensification; research into these novel technologies is now being pursued by the Process Intensification Group at Newcastle University.
 * Winnington and Wallerscote (in Northwich, Cheshire): It was here that ICI manufactured sodium carbonate (soda ash) and its various by-products such as sodium bicarbonate (bicarbonate of soda), and sodium sesquicarbonate. The Winnington site, built in 1873 by the entrepreneurs John Tomlinson Brunner and Ludwig Mond, was also the base for the former company Brunner, Mond & Co. Ltd. and, after the merger which created ICI, the powerful and influential Alkali Division. It was at the laboratories on this site that polythene was discovered by accident in 1933 during experiments into high pressure reactions. Wallerscote was built in 1926, its construction delayed by the First World War, and became one of the largest factories devoted to a single product (soda ash) in the world. However, the decreasing importance of the soda ash trade to ICI in favour of newer products such as paints and plastics, meant that in 1984 the Wallerscote site was closed, and thereafter mostly demolished. The laboratory where polythene was discovered was sold off and the building became home to a variety of businesses including a go-kart track and paintballing, and the Winnington Works were divested to the newly formed company, Brunner Mond, in 1991. It was again sold in 2006, to Tata (an Indian-based company) and in 2011 was re branded as Tata Chemicals Europe. The Winnington plant closed in February 2014, with the last shift on 2 February bringing to a close 140 years of soda ash production in this Northwich site.
 * Ardeer (in Stevenston, Ayrshire): ICI Nobel used the site to manufacture dynamite and other explosives and nitrocellulose-based products. For a time, the site also produced nylon and nitric acid. Nobel Enterprises was sold in 2002 to Inabata.
 * Penrhyndeudraeth (Gwynedd, North Wales): Cooke’s Works, part of ICI’s Nobel’s Explosives Company division produced nitroglycerine-based explosives up until the site’s closure in 1995.
 * Slough (in Berkshire): Headquarters of ICI Paints Division.
 * Stowmarket : Plant Manufacturing White, and off white Paints
 * Prudhoe - Plant Manufacturing Hammerite Paints
 * Birmingham: Plant Manufacturing Packaging Coatings for food and beverage cans
 * Welwyn Garden City (in Hertfordshire): Headquarters of ICI Plastics Division until the early 1990s.

Argentina
An ICI subsidiary called Duperial operated in Argentine from 1928 to 1995, when it was renamed ICI.

Established in the city of San Lorenzo, Santa Fe, it operates an integrated production site with commercial offices in Buenos Aires. Since 2009 it has made sulphuric acid with ISO certification under the company name Akzo Nobel Functional Chemicals S.A.

It also had an operation at Palmira, Mendoza, for its Wine Chemicals Division, that manufactured tartaric acid, wine alcohol and grapeseed oil from natural raw material coming from the wine industry in the provinces of Mendoza and San Juan. This operation held 10% world market share for tartaric acid. It was sold in 2008 and currently operates as Derivados Vínicos S.A. (DERVINSA).

Australia
The subsidiary ICI Australia Ltd established the Dry Creek Saltfields at Dry Creek north of Adelaide, South Australia, in 1940, with an associated soda ash plant at nearby Osborne. In 1989, these operations were sold to Penrice Soda Products. An ICI plant was built at Botany Bay in New South Wales in the 1940s and was part of the Orica demerger in 1997.

The plant once manufactured paints, plastics and industrial chemicals such as solvents. It was responsible for the Botany Bay Groundwater Plume contamination of a local aquifer.

Bangladesh
In 1968 a subsidiary of Imperial Chemical Industries (ICI) was established in then-East Pakistan. After Bangladesh gained independence in 1971, the company was incorporated on 24 January 1973 as ICI Bangladesh Manufacturers Limited and also as Public Limited Company. The company divested its investment in Bangladesh and was renamed as Advanced Chemical Industries Limited (ACI Limited) on 5 May 1992. The company sold its insect control, air care and toilet care brands to SC Johnson & Son in 2015. Currently Advanced Chemical Industries (ACI) Limited is one of the largest conglomerates in Bangladesh with a multinational heritage operating across the country. The company operates through three reporting divisions: Pharmaceuticals, Consumer Brands and Agribusiness.

Sri Lanka
ICI maintained offices in Colombo importing and supplying chemicals for manufacturers in Ceylon. In 1964, following import restrictions that allowed only locally owned subsidiaries of multinational companies to gain import licenses, Chemical Industries (Colombo) Limited was formed as an ICI subsidiary with 49% ICI ownership and remaining held public.

New Zealand
The subsidiary ICI New Zealand provided substantial quantities of chemical products – including swimming pool chemicals, commercial healthcare products, herbicides and pesticides for use within New Zealand and the neighbouring Pacific Islands.

A fire at the ICI New Zealand store in Mount Wellington, Auckland, on 21 December 1984, killed an ICI employee and caused major health concerns. Over 200 firefighters were exposed to toxic smoke and effluents during the firefighting efforts. Six firefighters retired for medical reasons as a result of the fire. This incident was a major event in the history of the New Zealand Fire Service and subject to a formal investigation, led by future Chief Justice Sian Elias. The fire was a trigger for major reforms of the service; direct consequences included improved protective clothing for firefighters, a standard safety protocol for major incidents, the introduction of dedicated fireground safety officers, and changes to occupational health regulations.

title: Imperial Chemical Industries


text:
Imperial Airways

Imperial Airways was an early British commercial long-range airline, operating from 1924 to 1939 and principally serving the British Empire routes to South Africa, India, Australia and the Far East, including Malaya and Hong Kong. Passengers were typically businessmen or colonial administrators, and most flights carried about 20 passengers or fewer. Accidents were frequent: in the first six years, 32 people died in seven incidents. Imperial Airways never achieved the levels of technological innovation of its competitors and was merged into the British Overseas Airways Corporation (BOAC) in 1939. BOAC in turn merged with the British European Airways (BEA) in 1974 to form British Airways.

Background
The establishment of Imperial Airways occurred in the context of facilitating British colonialism by making travel to and from the colonies quicker than travel by ship. Air travel would speed up both colonial government and trade. The launch of the airline followed a burst of air route surveying in the British Empire after the First World War, and after some experimental (and often dangerous) long-distance flying to the margins of Empire.

Formation
Imperial Airways was created against a background of stiff competition from French and German airlines that enjoyed heavy government subsidies and following the advice of the government's Hambling Committee (formally known as the C.A.T Subsidies Committee) under Sir Herbert Hambling. The committee, set up on 2 January 1923, produced a report on 15 February 1923 recommending that four of the largest existing airlines, the Instone Air Line Company, owned by shipping magnate Samuel Instone, Noel Pemberton Billing's British Marine Air Navigation (part of the Supermarine flying-boat company), the Daimler Airway, under the management of George Edward Woods, and Handley Page Transport Co Ltd., should be merged. It was hoped that this would create a company which could compete against French and German competition and would be strong enough to develop Britain's external air services while minimizing government subsidies for duplicated services. With this in view, a £1m subsidy over ten years was offered to encourage the merger. Agreement was made between the President of the Air Council and the British, Foreign and Colonial Corporation on 3 December 1923 for the company, under the title of the 'Imperial Air Transport Company' to acquire existing air transport services in the UK. The agreement set out the government subsidies for the new company: £137,000 in the first year diminishing to £32,000 in the tenth year as well as minimum mileages to be achieved and penalties if these weren't met.

Imperial Airways Limited was formed on 31 March 1924 with equipment from each contributing concern: British Marine Air Navigation Company Ltd, the Daimler Airway, Handley Page Transport Ltd and the Instone Air Line Ltd. Sir Eric Geddes was appointed the chairman of the board with one director from each of the merged companies. The government had appointed two directors, Hambling (who was also President of the Institute of Bankers) and Major John Hills, a former Treasury Financial Secretary.

The land operations were based at Croydon Airport to the south of London. IAL immediately discontinued its predecessors' service to points north of London, the airline being focused on international and imperial service rather than domestic. Thereafter the only IAL aircraft operating 'North of Watford' were charter flights.

Industrial troubles with the pilots delayed the start of services until 26 April 1924, when a daily London–Paris route was opened with a de Havilland DH.34. Thereafter the task of expanding the routes between England and the Continent began, with Southampton–Guernsey on 1 May 1924, London-Brussels–Cologne on 3 May, London–Amsterdam on 2 June 1924, and a summer service from London–Paris–Basel–Zürich on 17 June 1924. The first new airliner ordered by Imperial Airways, was the Handley Page W8f City of Washington, delivered on 3 November 1924. In the first year of operation the company carried 11,395 passengers and 212,380 letters. In April 1925, the film The Lost World became the first film to be screened for passengers on a scheduled airliner flight when it was shown on the London-Paris route.

Route proving
Between 16 November 1925 and 13 March 1926, Alan Cobham made an Imperial Airways' route survey flight from the UK to Cape Town and back in the Armstrong Siddeley Jaguar–powered de Havilland DH.50J floatplane G-EBFO. The outward route was London–Paris–Marseille–Pisa–Taranto–Athens–Sollum–Cairo–Luxor–Aswan–Wadi Halfa–Atbara–Khartoum–Malakal–Mongalla–Jinja–Kisumu–Tabora–Abercorn–Ndola–Broken Hill–Livingstone–Bulawayo–Pretoria–Johannesburg–Kimberley–Bloemfontein–Cape Town. On his return Cobham was awarded the Air Force Cross for his services to aviation.

On 30 June 1926, Cobham took off from the River Medway at Rochester in G-EBFO to make an Imperial Airways route survey for a service to Melbourne, arriving on 15 August 1926. He left Melbourne on 29 August 1926, and, after completing 28000 nmi in 320 hours flying time over 78 days, he alighted on the Thames at Westminster on 1 October 1926. Cobham was met by the Secretary of State for Air, Sir Samuel Hoare, and was subsequently knighted by HM King George V.

On 27 December 1926, Imperial Airways de Havilland DH.66 Hercules G-EBMX City of Delhi left Croydon for a survey flight to India. The flight reached Karachi on 6 January 1927 and Delhi on 8 January 1927. The aircraft was named by Lady Irwin, wife of the Viceroy, on 10 January 1927. The return flight left on 1 February 1927 and arrived at Heliopolis, Cairo on 7 February 1927. The flying time from Croydon to Delhi was 62 hours 27 minutes and Delhi to Heliopolis 32 hours 50 minutes.

The Eastern Route

Regular services on the Cairo to Basra route began on 12 January 1927 using DH.66 aircraft, replacing the previous RAF mail flight. Following two years of negotiations with the Persian authorities regarding overflight rights, a London to Karachi service started on 30 March 1929, taking seven days and consisting of a flight from London to Basel, a train to Genoa and a Short S.8 Calcutta flying boats to Alexandria, a train to Cairo and finally a DH.66 flight to Karachi. The route was extended as far as Delhi on 29 December 1929. The route across Europe and the Mediterranean changed many times over the next few years but almost always involved a rail journey.

In April 1931 an experimental London-Australia air mail flight took place; the mail was transferred at the Dutch East Indies, after the DH66 City of Cairo crashed landed in Timor, on the 19th April, having run out of fuel, and took 26 days in total to reach Sydney. For the passenger flight leaving London on 1 October 1932, the Eastern route was switched from the Persian to the Arabian side of the Persian Gulf, and Handley Page HP 42 airliners were introduced on the Cairo to Karachi sector. The move saw the establishment of an airport and rest house, Mahatta Fort, in the Trucial State of Sharjah now part of the United Arab Emirates.

On 29 May 1933 an England to Australia survey flight took off, operated by Imperial Airways Armstrong Whitworth Atalanta G-ABTL Astraea. Major H. G. Brackley, Imperial Airways' Air Superintendent, was in charge of the flight. Astraea flew Croydon-Paris-Lyon-Rome-Brindisi-Athens-Alexandria-Cairo where it followed the normal route to Karachi then onwards to Jodhpur-Delhi-Calcutta-Akyab-Rangoon-Bangkok-Prachuab-Alor Setar-Singapore-Palembang-Batavia-Sourabaya-Bima-Koepang-Bathurst Island-Darwin-Newcastle Waters-Camooweal-Cloncurry-Longreach-Roma-Toowoomba reaching Eagle Farm, Brisbane on 23 June. Sydney was visited on 26 June, Canberra on 28 June and Melbourne on 29 June.

There followed a rapid eastern extension. The first London to Calcutta service departed on 1 July 1933, the first London to Rangoon service on 23 September 1933, the first London to Singapore service on 9 December 1933, and the first London to Brisbane service on 8 December 1934, with Qantas responsible for the Singapore to Brisbane sector. (The 1934 start was for mail; passenger flights to Brisbane began the following April.) The first London to Hong Kong passengers departed London on 14 March 1936 following the establishment of a branch from Penang to Hong Kong.

The Africa Route

On 28 February 1931 a weekly service began between London and Mwanza on Lake Victoria in Tanganyika as part of the proposed route to Cape Town. On 9 December 1931 the Imperial Airways' service for Central Africa was extended experimentally to Cape Town for the carriage of Christmas mail. The aircraft used on the last sector, DH66 G-AARY City of Karachi arrived in Cape Town on 21 December 1931. On 20 January 1932 a mail-only route to London to Cape Town was opened. On 27 April this route was opened to passengers and took 10 days. In early 1933 Atalantas replaced the DH.66s on the Kisumu to Cape Town sector of the London to Cape Town route. On 9 February 1936 the trans-Africa route was opened by Imperial Airways between Khartoum and Kano in Nigeria. This route was extended to Lagos on 15 October 1936.

Short Empire flying boats

In 1937 with the introduction of Short Empire flying boats built at Short Brothers, Imperial Airways could offer a through-service from Southampton to the Empire. The journey to the Cape was via Marseille, Rome, Brindisi, Athens, Alexandria, Khartoum, Port Bell, Kisumu and onwards by land-based craft to Nairobi, Mbeya and eventually Cape Town. Survey flights were also made across the Atlantic and to New Zealand. By mid-1937 Imperial had completed its thousandth service to the Empire. Starting in 1938 Empire flying boats also flew between Britain and Australia via India and the Middle East.

In March 1939 three Shorts a week left Southampton for Australia, reaching Sydney after ten days of flying and nine overnight stops. Three more left for South Africa, taking six flying days to Durban.

Passengers
Imperial's aircraft were small, most seating fewer than twenty passengers; about 50,000 passengers used Imperial Airways in the 1930s. Most passengers on intercontinental routes or on services within and between British colonies were men in colonial administration, business or research. To begin with only the wealthy could afford to fly, but passenger lists gradually diversified. Travel experiences related to flying low and slow, and were reported enthusiastically in newspapers, magazines and books. There was opportunity for sightseeing from the air and at stops.

Crews
Imperial Airways stationed its all-male flight deck crew, cabin crew and ground crew along the length of its routes. Specialist engineers and inspectors – and ground crew on rotation or leave – travelled on the airline without generating any seat revenue. Several air crew lost their lives in accidents. At the end of the 1930s crew numbers approximated 3,000. All crew were expected to be ambassadors for Britain and the British Empire.

Air Mail

In 1934 the government began negotiations with Imperial Airways to establish a service (Empire Air Mail Scheme) to carry mail by air on routes served by the airline. Indirectly these negotiations led to the dismissal in 1936 of Sir Christopher Bullock, the Permanent Under-Secretary at the Air Ministry, who was found by a Board of Inquiry to have abused his position in seeking a position on the board of the company while these negotiations were in train. The government, including the Prime Minister, regretted the decision to dismiss him, later finding that, in fact, no corruption was alleged and sought Bullock's reinstatement which he declined.

The Empire Air Mail Programme started in July 1937, delivering anywhere for 1$1⁄2$ d./oz. By mid-1938 a hundred tons of mail had been delivered to India and a similar amount to Africa. In the same year, construction was started on the Empire Terminal in Victoria, London, designed by A. Lakeman and with a statue by Eric Broadbent, Speed Wings Over the World gracing the portal above the main entrance. From the terminal there were train connections to Imperial's flying boats at Southampton and coaches to its landplane base at Croydon Airport. The terminal operated as recently as 1980.

To help promote use of the Air Mail service, in June and July 1939, Imperial Airways participated with Pan American Airways in providing a special "around the world" service; Imperial carried the souvenir mail from Foynes, Ireland, to Hong Kong, out of the eastbound New York to New York route. Pan American provided service from New York to Foynes (departing 24 June, via the first flight of Northern FAM 18) and Hong Kong to San Francisco (via FAM 14), and United Airlines carried it on the final leg from San Francisco to New York, arriving on 28 July.

Captain H. W. C. Alger was the pilot for the inaugural air mail flight carrying mail from England to Australia for the first time on the Short Empire flyingboat Castor for Imperial Airways' Empires Air Routes, in 1937.

In November 2016, 80 years later, the Crete2Cape Vintage Air Rally flew this old route with fifteen vintage aeroplanes – a celebration of the skill and determination of these early aviators.

Second World War
Before the outbreak of war on 1 September 1939, the British government had already implemented the Air Navigation (Restriction in Time of War) Order 1939. That ordered military takeover of most civilian airfields in the UK, cessation of all private flying without individual flight permits, and other emergency measures. It was administered by a statutory department of the Air Ministry titled National Air Communications (NAC). By 1 September 1939, the aircraft and administrations of Imperial Airways and British Airways Ltd were physically transferred to Bristol (Whitchurch) Airport, to be operated jointly by NAC. On 1 April 1940, Imperial Airways Ltd and British Airways Ltd were officially combined into a new company, British Overseas Airways Corporation (BOAC), that had already been formed on 24 November 1939 with retrospective financial arrangements.

1920s

 * 24 December 1924: de Havilland DH.34 G-EBBX City of Delhi crashed and caught fire shortly after take-off from Croydon Airport, killing the pilot and all seven passengers.
 * 13 July 1928: Vickers Vulcan G-EBLB crashed at Purley during a test flight, killing four of the six people on board. As a result of the crash, Imperial Airways stopped the flying of staff (so called joy rides) during test flights.
 * 17 June 1929: Handley Page W.10 G-EBMT City of Ottawa ditched in the English Channel following engine failure whilst on a flight from Croydon to Paris with the loss of seven lives.
 * 6 September 1929: de Havilland Hercules G-EBMZ City of Jerusalem crashed and burned on landing at Jask, Iran in the dark due to the pilot misjudging the altitude and stalling the aircraft, killing three of five on board.
 * 26 October 1929: Short Calcutta G-AADN City of Rome force-landed off La Spezia, Italy in poor weather; the flying boat sank in the night during attempts to tow it to shore, killing all seven on board.

1930s

 * 30 October 1930: Handley Page W.8g G-EBIX City of Washington struck high ground in fog at Boulogne, Paris, France, killing three of six on board.
 * 28 March 1933: Armstrong Whitworth Argosy G-AACI City of Liverpool crashed at Diksmuide, Belgium following an in-flight fire. This is suspected to be the first case of sabotage in the air. All fifteen people on board were killed.
 * 30 December 1933: Avro Ten G-ABLU Apollo collided with a radio mast at Ruysselede, Belgium and crashed. All ten people on board were killed.
 * 31 December 1935: Short Calcutta G-AASJ City of Khartoum crashed off Alexandria, Egypt when all four engines failed on approach, possibly due to fuel starvation; twelve of 13 on board drowned when the flying boat sank.
 * 22 August 1936: Short Kent G-ABFA Scipio sank at Mirabello Bay, Crete after a heavy landing, killing two of 11 on board.
 * 24 March 1937: Short Empire G-ADVA Capricornus  crashed in the Beaujolois Mountains near Ouroux, France, following a navigation error, killing five.
 * 1 October 1937: Short Empire G-ADVC Courtier crashed on landing in Phaleron Bay, Greece due to poor visibility, killing two of 15 on board.
 * 5 December 1937: Short Empire G-ADUZ Cygnus  crashed on takeoff from Brindisi, Italy due to incorrect flap settings, killing two.
 * 27 July 1938: Armstrong Whitworth Atalanta G-ABTG Amalthea flew into a hillside near Kisumu, Kenya shortly after takeoff, killing all four on board.
 * 27 November 1938: Short Empire G-AETW Calpurnia crashed in Lake Habbaniyah, Iraq in bad weather after the pilot descended to maintain visual contact with the ground following spatial disorientation, killing all four crew.
 * 21 January 1939: Short Empire G-ADUU Cavalier ditched in the Atlantic 285 mi off New York due to carburettor icing and loss of engine power; three drowned while ten survivors were picked up by the tanker Esso Baytown. Thereafter Imperial Airways and Pan-American trans-oceanic flying boats had the upper surfaces of the wings painted with orange high visibility markings.
 * 1 May 1939: Short Empire G-ADVD Challenger crashed in the Lumbo lagoon while attempting to land at Lumbo Airport, killing two of six on board.

1940

 * 1 March 1940: Flight 197, operated by Handley Page H.P.42 G-AAGX Hannibal, disappeared over the Gulf of Oman with eight on board; no wreckage, cargo or occupants have been found. The cause of the crash remains unknown, but fuel starvation, a bird strike damaging a propeller and causing an engine or wing to separate, an in-flight breakup or multiple engine failure were theorized. Two months after the crash, the H.P.42 was withdrawn from passenger operations. It was also recommended that all commercial aircraft used in long flights over water be equipped with personal and group life saving gear; this would later become standard throughout the airline industry.

Non-fatal accidents

 * 21 October 1926: Handley Page W.10 G-EBMS  City of Melbourne ditched in the English Channel 18 nmi off the English coast after an engine failed. All 12 people on board were rescued by FV Invicta.
 * 19 April 1931: de Havilland DH.66 Hercules with registration G-EBMW, damaged beyond repair in a forced landing following fuel starvation at Surabaya. The airplane operated on a trial mail flight from India to Melbourne with en route stops at Semarang, Soerabaja and Kupang.
 * 8 August 1931: Handley Page H.P.42 G-AAGX Hannibal was operating a scheduled passenger flight from Croydon to Paris when an engine failed and debris forced a second engine to be shut down. A forced landing at Five Oak Green, Kent resulted in extensive damage. No injuries occurred. Hannibal was dismantled and trucked to Croydon to be rebuilt.
 * 9 November 1935: Short Kent G-ABFB Sylvanus caught fire and burned out during refueling in Brindisi Harbor; the refueling crew were able to jump clear of the burning aircraft and survived.
 * 29 September 1936: Armstrong Whitworth Atalanta G-ABTK burned out in a hangar fire at Delhi, India.
 * 31 May 1937: Handley Page H.P.45 (former H.P.42) G-AAXE Hengist was destroyed in a hangar fire at Karachi, India.
 * 3 December 1938: de Havilland Express G-ADCN burned out at Bangkok.
 * 12 March 1939: Short S.23 Empire Flying Boat Mk 1 G-ADUY, damaged beyond repair at Tandjong, Batavia, Netherlands East Indies. Struck a submerged object while taxiing after alighting. Aircraft beached but damaged beyond repair by immersion and mishandling during salvage. Aircraft dismantled and shipped to England but not returned to service.
 * 7 November 1939: Handley Page H.P.42 G-AXXD Horatius was written off following a forced landing at a golf course at Tiverton, Devon.
 * 19 March 1940: Handley Page H.P.45 G-AAXC Heracles and H.P.42 G-AAUD Hanno were written off after being blown over in a windstorm while parked at Whitchurch Airport.

Aircraft
Imperial Airways operated many types of aircraft from its formation on 1 April 1924 until 1 April 1940 when all aircraft still in service were transferred to BOAC.

title: Imperial Airways