Professor
Lydia
Bourouiba
the
Massachusetts
Institute
Technology
(
MIT
)
used
high
-
speed
cameras
to
capture
a
cough
projecting
miniature
specks
far
as
six
metres
.
She
is
critical
the
current
safety
guidance
:
"
Having
this
false
idea
of
safety
at
one
to
two
metres
-
somehow
drops
will
just
fall
to
the
ground
at
that
distance
-
is
not
based
on
we
have
quantified
,
measured
and
visualised
directly
.
"
And
a
study
carried
out
at
hospitals
in
China
,
found
traces
of
coronavirus
in
Covid
-
19
wards
and
intensive
care
units
,
estimated
four
metres
is
a
better
safe
distance
.
But
for
the
US
Centres
for
Disease
Control
,
the
role
of
aerosols
in
spreading
the
virus
is
"
currently
uncertain
"
.
And
what's
still
not
established
is
whether
any
virus
that
spreads
further
two
metres
can
still
be
infectious
.
Reference
:
Shukman
,
D
.
(
2020
)
.
Social
distancing
and
coronavirus
:
The
science
behind
the
two
-
metre
rule
.
BBC
News
.