On 1st August 2022, Envair celebrates its 50th birthday. In that time, there has been a transformation in clean air and containment technology. We took a trip down memory lane with Gary Bagshaw, who has been MD since 2006, and one of our original founders, John Neiger, to look at the milestones that changed our industry.

50 years ago, the clean air and containment sector didn’t really exist – there was no regulated industry to speak of as such. This started to change gradually, and it gave companies like Envair a reason to exist. Our founders were motivated by a desire to use their engineering skills in environmental control, a value that has remained constant ever since.

Initially, standards were introduced for drugs and chemicals manufactured in labs that helped protect operators and the end user. New technologies then helped to validate processes, and more recently, we’ve seen the integration of third party solutions that are enhancing production methods and creating new levels of efficiency.

Setting new standards

Envair was born in Lancashire, shaped by the heavy industries that were present in the region at the time including cotton and mining. We started out by making horizontal and vertical laminar flow cabinets, constructed from MDF and incorporating fans and HEPA filters. We were led by managing director Peter Starkey, who had previously been involved in a company that sold filters, developed from ones that protected miners from coal dust.

We had only been in existence for a short time when we found ourselves building cleanrooms for companies who were at the forefront of their respective fields.
Among them were glass manufacturer Pilkington, who needed cleanrooms for the production of head-up displays in fighter jets and for the extrusion of fibre optic cables, British Aerospace, who needed them for the manufacture and maintenance of instrumentation, and electrical engineering firm Ferranti who used them in the manufacture of semiconductor devices.

Further afield were diamond company De Beers in Ireland, who wanted to avoid contamination while grading industrial diamond powders and the Government Veterinary Service in Iceland who needed to be self-sufficient in the production of animal vaccines.

By the end of the decade, demand for cleanroom technology was growing, as was our client list. At the same time, the company was called into action by a singular tragedy. In 1978, a medical photographer called Janet Parker died of smallpox thought to have been contracted from a poorly maintained service duct running between her workplace and a research laboratory above. This incident led to the creation of British Standard BS 5726:1979 for microbiological safety cabinets and to our company entering a new area with its first range of microbiological safety cabinets. Indeed, we went on to play a leading role in that sector, with John Neiger joining the British Standards committee for microbiological safety cabinets.

It took a further ten years for most UK hospital pathology labs to be equipped with Class I microbiological safety cabinets which offered operator protection only, whilst research laboratories including at AstraZeneca and GSK were investing in Class II cabinets which also protected the product.

We developed our expertise in this area, and continued to supply all classes of MSCs to various disease and defence establishments until slowly the emphasis shifted to cleanrooms for aseptic units in hospitals.

This led to the next great leap forward for Envair. Senior pharmacists at two major hospitals, the Royal Liverpool and Sheffield Hallamshire, worked with us to develop and test prototypes of what quickly became Envair’s two main isolator ranges: Pharm-Assist positive pressure isolators for TPNs and IVs and CDC negative pressure isolators for cytotoxic.

Isolators are effectively sealed enclosures with filtered airflow systems, operator access via glove-sleeve systems and material ingress and egress via transfer chambers or transfer devices. Again, Envair were at the forefront of this technology in the UK, with John Neiger on the UK Pharmaceutical Isolator Working Group and co-author of ‘Pharmaceutical Isolators’ which was published in 2004.

ISO 14644-7:2004 Cleanrooms and associated controlled environments — Part 7: Separative devices (clean air hoods, gloveboxes, isolators and mini-environments), widely known as the isolator standard, was published in the same year. Another important document was the EU GMP Annex 1: Manufacture of Sterile Medicinal Products first published in 1989. Early versions described the requirements for cleanroom technology, but isolator technology was recognised in the early 2000s and, eventually, in the most recent revisions, became the technology of choice along with RABS (Restricted Access Barrier Systems).

The various standards and guidelines did a huge amount to change working practices in the industry. For example, where engineers had previously carried out pressure decay testing for isolator leaks every six months or so, the guidelines turned this into a routine weekly duty for operators with the test built in to the instrumentation of the isolator itself, thus also facilitating validation.

Using new technology

This need to validate processes, in a repeatable way, and reduce the potential for human error has been a huge driver for the development of the new technology that has entered the industry. This includes solutions that now seem simple by today’s standards, such as interlocking doors.

It wasn’t until the mid ‘90s that the risk of operators leaving two doors of an isolator open at once, creating an obvious risk of contamination, was recognised. Envair solved this problem by using interlocked and timed electromagnetic doors which proved to be a more reliable solution than alternative methods in use at the time.

Other developments to help operators have included the introduction of touch screen displays inside the cabinets. Again, this now seems like a simple innovation, but it has transformed the experience of using isolators, and marked a sea change from the cumbersome combination of buttons, dials and gauges that preceded it. In the words of one pharmaceutical employee, this is ‘like going from a Nokia 3310 to an iPhone.’

The big benefit this had for operators was comfort. They no longer had to contort themselves to read instructions on the outside of the isolator while having their hands buried in gloves inside – and that had its own implications for the integrity of the drugs they were working on. An operator who is both comfortable and in control is much less likely to make mistakes.