SEATTLE • It is crystal-clear that the centrepiece of Apple's new headquarters - a massive, ring-shaped office - are panes of glass, a testament to the company's famed design-obsessed aesthetic.
But there has been one design hiccup since the building opened last year. Employees keep smacking into the glass.
Surrounding the Cupertino, California-based building are 13.7m-tall curved panels of safety glass.
Inside are work spaces, dubbed "pods", which are also made with a lot of glass.
Apple staff are often glued to the iPhones they helped popularise. That has resulted in repeated cases of distracted employees walking into the panes , according to people familiar with the incidents.
Seven people "physically hurt" themselves on the first day the campus opened, claimed Twitter user Kenn Durre.
Staff began moving into the campus, which was commissioned by Apple's chief designer Jonathan Ive after eight years in the making, in April last year.
With the design flaw proving a headache to staff, some employees began to stick Post-It notes on the glass doors to mark their presence.
However, the notes were removed because they detracted from the design of the US$5-billion (S$6.6-billion) building.
Apart from that shortcoming, the Apple Park campus has been otherwise lauded as an architectural marvel. The building, crafted by famed architect Norman Foster, immortalised a vision that the company's co-founder Steve Jobs had years earlier.
In 2011, Jobs reportedly described the building in mind as "a little like a spaceship (had) landed".
He has also been credited for coming up with the glass pods, designed to mix solo office areas with more social spaces.
As with Apple's stylish products, Jobs wanted no seam, gap or paintbrush stroke showing.
Every wall, floor and even ceiling had to be polished to a pristine smoothness, an insider told Bloomberg Businessweek in 2013.
The building is designed to house some 13,000 employees.
Wired magazine, the first publication to pay a visit at its opening last year, described the structure as a "statement of openness, of free movement", in contrast to Apple's typically insular culture.
"While it is a technical marvel to make glass at this scale, that's not the achievement," Mr Ive told the magazine in May.
"The achievement is to make a building where so many people can connect and collaborate and walk and talk."
Yet, some of the talk has switched to the unfortunate bumps with the glass.
It is not clear how many incidents there have been.
A Silicon Valley-based spokesman for the Occupational Safety and Health Administration referred questions about Apple's workplace safety record to the government agency's website.
A search on the site based on Apple's name in California found no reports of injuries at the company's new campus.
It is not the first time Apple's penchant for glass in buildings has caused problems.
In late 2011, 83-year-old Evelyn Paswall walked into the glass wall of an Apple store, breaking her nose.
She sued the company, arguing it should have posted a warning on the glass. The suit was settled without any cost to Apple, according to a legal filing in early 2013.