a very basic Runspace blueprint

basicRunspace.ps1

$Action = { }
try {
    $iss = [initialsessionstate]::CreateDefault2()
    $rs = [runspacefactory]::CreateRunspace($Host, $iss)
    $rs.Open()
    $ps = [powershell]::Create()
    $ps.Runspace = $rs
    $ps.AddScript($Action).Invoke()
    foreach ($e in $ps.Streams.Error) {
        # non-terminating error here
        $e
    }
}
catch {
    # terminating error here
}
finally {
    if ($null -ne $ps) {
        $ps.Dispose()
    }

    if ($null -ne $rs) {
        $rs.Dispose()
    }
}